[PATCH] Add support for stack-protector
Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Cc: Jagan Teki jagan@amarulasolutions.com Cc: Kever Yang kever.yang@rock-chips.com Cc: Heinrich Schuchardt xypron.glpk@gmx.de Cc: AKASHI Takahiro takahiro.akashi@linaro.org Cc: Usama Arif usama.arif@arm.com Cc: Sam Protsenko joe.skb7@gmail.com Cc: Masahiro Yamada masahiroy@kernel.org Cc: Philippe Reynes philippe.reynes@softathome.com Cc: Eugeniu Rosca roscaeugeniu@gmail.com Cc: Jan Kiszka jan.kiszka@siemens.com
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
---
Makefile | 4 ++++ common/Kconfig | 15 +++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 17 +++++++++++++++++ scripts/Makefile.spl | 6 ++++++ 5 files changed, 44 insertions(+) create mode 100644 common/stackprot.c
diff --git a/Makefile b/Makefile index 3ee4cc00dd..6e7a81ec7d 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,11 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9ba1..e30c3c4ab8 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,21 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR + bool "Stack Protector buffer overflow detection" + default n + help + Enable stack smash detection through gcc built-in stack-protector + canary logic + +config SPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for SPL" + default n + +config TPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for SPL" + default n + endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d016..fe71e18317 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o + diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000000..7c95b8544f --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> + +DECLARE_GLOBAL_DATA_PTR; + +unsigned long __stack_chk_guard = 0xfeedf00ddeadbeef; + +void __stack_chk_fail(void) +{ + panic("Stack smashing detected in function: %p relocated from %p", + __builtin_return_address(0), + __builtin_return_address(0) - gd->reloc_off); +} diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 9f1f7445d7..1505e4e851 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -63,6 +63,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif + # FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS)
On 1/10/21 4:39 PM, Joel Peshkin wrote:
Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Cc: Jagan Teki jagan@amarulasolutions.com Cc: Kever Yang kever.yang@rock-chips.com Cc: Heinrich Schuchardt xypron.glpk@gmx.de Cc: AKASHI Takahiro takahiro.akashi@linaro.org Cc: Usama Arif usama.arif@arm.com Cc: Sam Protsenko joe.skb7@gmail.com Cc: Masahiro Yamada masahiroy@kernel.org Cc: Philippe Reynes philippe.reynes@softathome.com Cc: Eugeniu Rosca roscaeugeniu@gmail.com Cc: Jan Kiszka jan.kiszka@siemens.com
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
Makefile | 4 ++++ common/Kconfig | 15 +++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 17 +++++++++++++++++ scripts/Makefile.spl | 6 ++++++ 5 files changed, 44 insertions(+) create mode 100644 common/stackprot.c
diff --git a/Makefile b/Makefile index 3ee4cc00dd..6e7a81ec7d 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,11 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9ba1..e30c3c4ab8 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,21 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR
- bool "Stack Protector buffer overflow detection"
- default n
- help
Enable stack smash detection through gcc built-in stack-protectorcanary logic+config SPL_STACKPROTECTOR
- bool "Stack Protector buffer overflow detection for SPL"
- default n
+config TPL_STACKPROTECTOR
- bool "Stack Protector buffer overflow detection for SPL"
%s/SPL/TPL/
default n
endmenu
menu "Update support"
diff --git a/common/Makefile b/common/Makefile index bcf352d016..fe71e18317 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o
diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000000..7c95b8544f --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021 Broadcom
- */
+#include <common.h>
+DECLARE_GLOBAL_DATA_PTR;
+unsigned long __stack_chk_guard = 0xfeedf00ddeadbeef;
+void __stack_chk_fail(void)
The standalone EFI binaries are compiled with -fstack-protector-strong when selecting CONFIG_STACKPROTECTOR.
Do we need a function __stack_chk_fail) in lib/efi_selftest/efi_freestanding.c and lib/efi_loader/efi_freestanding.c too?
Could you, please, provide unit tests demonstrating that the stack protection is actually working SPL, main U-Boot, and the EFI binaries.
Best regards
Heinrich
+{
- panic("Stack smashing detected in function: %p relocated from %p",
__builtin_return_address(0),__builtin_return_address(0) - gd->reloc_off);+} diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 9f1f7445d7..1505e4e851 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -63,6 +63,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif
- # FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS)
Hi Heinrich,
Thank you for your comments. I have 2 questions about how to proceed....
1) Unit test I can add a function that can be used to trigger an overrun, but I am not sure where to include it as the stack protector prints the error message and then resets uboot so it wouldn't fir in a unit test suite.
I could add a CONFIG_STACKPROTECTOR_TEST_FAIL to add a "test_stackprotector fail" command to the CLI and you could call the underlying stackprot_test_fail() from code hacked into SPL and TPL
2) Standalone/EFI What we did for our own standalone code was to add the KBUILD_CFLAGS += -fno-stack-protector to the Makefile for our specific standalone. The problem is there is no generic place from which all standalone/EFI is called, so I could just leave this for maintainers of specific standalone/EPI programs to add IF they are enabling STACKPROTECTOR (If they don't enable it, they don't need to do anything) or I could add KBUILD_CFLAGS += -fno-stack-protector to both lib/efi_setlftest/Makefile and lib/efi_loader/Makefile
What would you suggest?
Regards,
Joel
Am 10. Januar 2021 20:44:15 MEZ schrieb Joel Peshkin joel.peshkin@broadcom.com:
Hi Heinrich,
Thank you for your comments. I have 2 questions about how to proceed....
- Unit test
I can add a function that can be used to trigger an overrun, but I am not sure where to include it as the stack protector prints the error message and then resets uboot so it wouldn't fir in a unit test suite.
I could add a CONFIG_STACKPROTECTOR_TEST_FAIL to add a "test_stackprotector fail" command to the CLI and you could call the underlying stackprot_test_fail() from code hacked into SPL and TPL
Additonally to the test command you will nedd a Python test (in /test/py/tests/) to excercise it.
- Standalone/EFI
What we did for our own standalone code was to add the KBUILD_CFLAGS += -fno-stack-protector to the Makefile for our specific standalone. The problem is there is no generic place from which all standalone/EFI is called, so I could just leave this for maintainers of specific standalone/EPI programs to add IF they are enabling STACKPROTECTOR (If they don't enable it, they don't need to do anything) or I could add KBUILD_CFLAGS += -fno-stack-protector to both
This would lead to contradictory arguments on the GCC command line.
lib/efi_setlftest/Makefile and lib/efi_loader/Makefile
Have a look at CFLAGS_REMOVE in aforementioned Makefiles.
Best regards
Heinrich
What would you suggest?
Regards,
Joel
Hi,
+unsigned long __stack_chk_guard = 0xfeedf00ddeadbeef;
sizeof(unsigned long) isn't always 8, even gcc issues a warning when it's invoked with proper options (e.g. 32-bit build):
warning: conversion from ‘long long unsigned int’ to ‘long unsigned int’ changes value from ‘18369602397475290863’ to ‘3735928559’ [-Woverflow]
Maybe there's some better way to initialize this variable. E.g. with #if … #else … #endif or using some initialization function that is invoked early. I should also mention that a fixed canary value doesn't actually bring proper protection against exploits, thus run-time initialization with a random value is usually preferred.
I'm not sure whether it's important at all in bootloader code, I just wanted to be sure that it isn't unnoticed.
Cheers, Alex.
Hi Alex,
Yeah, I think I'll wind up with some ifdef code for the static init. In the case of arm (32-bit), there is actually a GCC bug that causes it to use the address of the canary value instead of the canary value itself. GCC upstream just fixed that a few days ago, but it may be a year or so before the appropriate GCC version is widely available.
I may eventually add an optional mechanism to allow the value to be changed (very carefully) at runtime. This has to be done early enough that we cannot wait for an RNG to be identified via DTB, but there are a few ways to keep arm and aarch64 from being too predictable and some boards may have peripherals that can provide a sufficiently variable value.
-Joel
On Sun, Jan 10, 2021 at 2:40 PM Alex Sadovsky < nable.maininbox@googlemail.com> wrote:
Hi,
+unsigned long __stack_chk_guard = 0xfeedf00ddeadbeef;
sizeof(unsigned long) isn't always 8, even gcc issues a warning when it's invoked with proper options (e.g. 32-bit build):
warning: conversion from ‘long long unsigned int’ to ‘long unsigned int’
changes value from ‘18369602397475290863’ to ‘3735928559’ [-Woverflow]
Maybe there's some better way to initialize this variable. E.g. with #if … #else … #endif or using some initialization function that is invoked early. I should also mention that a fixed canary value doesn't actually bring proper protection against exploits, thus run-time initialization with a random value is usually preferred.
I'm not sure whether it's important at all in bootloader code, I just wanted to be sure that it isn't unnoticed.
Cheers, Alex.
Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Cc: Jagan Teki jagan@amarulasolutions.com Cc: Kever Yang kever.yang@rock-chips.com Cc: Heinrich Schuchardt xypron.glpk@gmx.de Cc: AKASHI Takahiro takahiro.akashi@linaro.org Cc: Usama Arif usama.arif@arm.com Cc: Sam Protsenko joe.skb7@gmail.com Cc: Masahiro Yamada masahiroy@kernel.org Cc: Philippe Reynes philippe.reynes@softathome.com Cc: Eugeniu Rosca roscaeugeniu@gmail.com Cc: Jan Kiszka jan.kiszka@siemens.com
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
Changes for v2: - Add test command and corresponding config - Fixed incorrect description in Kconfig - Add unit test --- Makefile | 4 +++ common/Kconfig | 22 ++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 44 ++++++++++++++++++++++++++++ configs/sandbox_defconfig | 2 ++ scripts/Makefile.spl | 6 ++++ test/py/tests/test_stackprotector.py | 15 ++++++++++ 7 files changed, 95 insertions(+) create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/Makefile b/Makefile index 3ee4cc00dd..6e7a81ec7d 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,11 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9ba1..f773babd3a 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,28 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR + bool "Stack Protector buffer overflow detection" + default n + help + Enable stack smash detection through gcc built-in stack-protector + canary logic + +config STACKPROTECTOR_TEST_COMMAND + bool "Test command for stack protector" + depends on STACKPROTECTOR + default n + help + Enable stackprot_test command + +config SPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for SPL" + default n + +config TPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for TPL" + default n + endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d016..fe71e18317 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o + diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000000..d602dc7de1 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> +#include <cli.h> +#include <command.h> +#include <console.h> + +DECLARE_GLOBAL_DATA_PTR; + +unsigned long __stack_chk_guard = + (unsigned long)((unsigned long long)0xfeedf00ddeadbeef & + ~((unsigned long)0)); + +void __stack_chk_fail(void) +{ + panic("Stack smashing detected in function: %p relocated from %p", + __builtin_return_address(0), + __builtin_return_address(0) - gd->reloc_off); +} + +#ifdef CONFIG_STACKPROTECTOR_TEST_COMMAND +static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]); + +int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + char a[128]; + char b[256]; + int i; + for (i = 0; i < 256; i++) { + b[i] = i; + } + memcpy(a, b, 512); + return (0); +} + +U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail, + "test stack protector fail", ""); + +#endif diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index f1ec701a9f..da3aca2551 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -274,3 +274,5 @@ CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y +CONFIG_STACKPROTECTOR=y +CONFIG_STACKPROTECTOR_TEST_COMMAND=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 9f1f7445d7..1505e4e851 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -63,6 +63,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif + # FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000000..49df8eff8c --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom + +import pytest +import signal + +@pytest.mark.buildconfigspec('stackprotector_test_command') +def test_stackprotector(u_boot_console): + """Test that the stackprotector function works.""" + + u_boot_console.run_command('stackprot_test',wait_for_prompt=False) + expected_response = 'Stack smashing detected' + u_boot_console.wait_for(expected_response) + assert(True) +
On 11.01.21 04:10, Joel Peshkin wrote:
Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Cc: Jagan Teki jagan@amarulasolutions.com Cc: Kever Yang kever.yang@rock-chips.com Cc: Heinrich Schuchardt xypron.glpk@gmx.de Cc: AKASHI Takahiro takahiro.akashi@linaro.org Cc: Usama Arif usama.arif@arm.com Cc: Sam Protsenko joe.skb7@gmail.com Cc: Masahiro Yamada masahiroy@kernel.org Cc: Philippe Reynes philippe.reynes@softathome.com Cc: Eugeniu Rosca roscaeugeniu@gmail.com Cc: Jan Kiszka jan.kiszka@siemens.com
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
Changes for v2:
- Add test command and corresponding config
- Fixed incorrect description in Kconfig
- Add unit test
Makefile | 4 +++ common/Kconfig | 22 ++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 44 ++++++++++++++++++++++++++++ configs/sandbox_defconfig | 2 ++ scripts/Makefile.spl | 6 ++++ test/py/tests/test_stackprotector.py | 15 ++++++++++ 7 files changed, 95 insertions(+) create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/Makefile b/Makefile index 3ee4cc00dd..6e7a81ec7d 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,11 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9ba1..f773babd3a 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,28 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR
- bool "Stack Protector buffer overflow detection"
- default n
- help
Enable stack smash detection through gcc built-in stack-protectorcanary logic+config STACKPROTECTOR_TEST_COMMAND
This should be called CMD_STACKPROTECTOR_TEST cmd/Kconfig.
- bool "Test command for stack protector"
- depends on STACKPROTECTOR
- default n
- help
Enable stackprot_test command+config SPL_STACKPROTECTOR
- bool "Stack Protector buffer overflow detection for SPL"
depends on SPL && STACKPROTECTOR
- default n
+config TPL_STACKPROTECTOR
- bool "Stack Protector buffer overflow detection for TPL"
depends on TPL && STACKPROTECTOR
- default n
endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d016..fe71e18317 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o
diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000000..d602dc7de1 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021 Broadcom
- */
+#include <common.h> +#include <cli.h> +#include <command.h> +#include <console.h>
+DECLARE_GLOBAL_DATA_PTR;
+unsigned long __stack_chk_guard =
- (unsigned long)((unsigned long long)0xfeedf00ddeadbeef &
~((unsigned long)0));
Please, use scripts/checkpatch.pl and correct the reported problems, e.g.
WARNING: please, no spaces at the start of a line #115: FILE: common/stackprot.c:14: + (unsigned long)((unsigned long long)0xfeedf00ddeadbeef &$
WARNING: Unnecessary typecast of c90 int constant #115: FILE: common/stackprot.c:14: + (unsigned long)((unsigned long long)0xfeedf00ddeadbeef &
WARNING: Unnecessary typecast of c90 int constant #116: FILE: common/stackprot.c:15: + ~((unsigned long)0));
+void __stack_chk_fail(void) +{
- panic("Stack smashing detected in function: %p relocated from %p",
__builtin_return_address(0),__builtin_return_address(0) - gd->reloc_off);+}
+#ifdef CONFIG_STACKPROTECTOR_TEST_COMMAND
The command should be in directory /cmd/. There you can use the Makefile to decide if it is compiled.
Please, add a short man-page to /doc/usage/. See doc/usage/button.rst for a template.
+static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[]);+int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])+{
- char a[128];
- char b[256];
- int i;
Missing empty line.
- for (i = 0; i < 256; i++) {
b[i] = i;- }
- memcpy(a, b, 512);
What is b[] good for? The following seems to be enough to do the test:
{ char a[128];
memset(a, 0xff, 512); return; }
Best regards
Heinrich
- return (0);
+}
+U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail,
"test stack protector fail", "");+#endif diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index f1ec701a9f..da3aca2551 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -274,3 +274,5 @@ CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y +CONFIG_STACKPROTECTOR=y +CONFIG_STACKPROTECTOR_TEST_COMMAND=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 9f1f7445d7..1505e4e851 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -63,6 +63,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif
# FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000000..49df8eff8c --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom
+import pytest +import signal
+@pytest.mark.buildconfigspec('stackprotector_test_command') +def test_stackprotector(u_boot_console):
- """Test that the stackprotector function works."""
- u_boot_console.run_command('stackprot_test',wait_for_prompt=False)
- expected_response = 'Stack smashing detected'
- u_boot_console.wait_for(expected_response)
- assert(True)
Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Cc: Jagan Teki jagan@amarulasolutions.com Cc: Kever Yang kever.yang@rock-chips.com Cc: Heinrich Schuchardt xypron.glpk@gmx.de Cc: AKASHI Takahiro takahiro.akashi@linaro.org Cc: Usama Arif usama.arif@arm.com Cc: Sam Protsenko joe.skb7@gmail.com Cc: Masahiro Yamada masahiroy@kernel.org Cc: Philippe Reynes philippe.reynes@softathome.com Cc: Eugeniu Rosca roscaeugeniu@gmail.com Cc: Jan Kiszka jan.kiszka@siemens.com
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
Changes for v3: - Move test command to cmd/ - Update Kconfig names and depends - clean up default canary initialization
Changes for v2: - Add test command and corresponding config - Fixed incorrect description in Kconfig - Add unit test --- MAINTAINERS | 7 +++++++ Makefile | 4 ++++ cmd/Kconfig | 10 ++++++++++ cmd/Makefile | 1 + cmd/stackprot_test.c | 26 ++++++++++++++++++++++++++ common/Kconfig | 17 +++++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 18 ++++++++++++++++++ configs/sandbox_defconfig | 2 ++ scripts/Makefile.spl | 6 ++++++ test/py/tests/test_stackprotector.py | 15 +++++++++++++++ 11 files changed, 108 insertions(+) create mode 100644 cmd/stackprot_test.c create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/MAINTAINERS b/MAINTAINERS index 52d7307525..2982ffcc07 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1022,6 +1022,13 @@ F: include/sqfs.h F: cmd/sqfs.c F: test/py/tests/test_fs/test_squashfs/
+STACKPROTECTOR +M: Joel Peshkin joel.peshkin@broadcom.com +S: Maintained +F: common/stackprot.c +F: cmd/stackprot_test.c +F: test/py/tests/test_stackprotector.py + TARGET_BCMNS3 M: Bharat Gooty bharat.gooty@broadcom.com M: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com diff --git a/Makefile b/Makefile index 3ee4cc00dd..6e7a81ec7d 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,11 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/cmd/Kconfig b/cmd/Kconfig index 1595de999b..04700e4bb4 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -2271,6 +2271,16 @@ config CMD_AVB avb read_part_hex - read data from partition and output to stdout avb write_part - write data to partition avb verify - run full verification chain + +config CMD_STACKPROTECTOR_TEST + bool "Test command for stack protector" + depends on STACKPROTECTOR + default n + help + Enable stackprot_test command + The stackprot_test command will force a stack overrun to test + the stack smashing detection mechanisms. + endmenu
config CMD_UBI diff --git a/cmd/Makefile b/cmd/Makefile index dd86675bf2..8e8fcea19e 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o obj-$(CONFIG_CMD_STRINGS) += strings.o obj-$(CONFIG_CMD_SMC) += smccc.o obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o obj-$(CONFIG_CMD_TERMINAL) += terminal.o obj-$(CONFIG_CMD_TIME) += time.o obj-$(CONFIG_CMD_TIMER) += timer.o diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c new file mode 100644 index 0000000000..ea952c075e --- /dev/null +++ b/cmd/stackprot_test.c @@ -0,0 +1,26 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> +#include <cli.h> +#include <command.h> +#include <console.h> + +DECLARE_GLOBAL_DATA_PTR; + +static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]); + +int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + char a[128]; + + memset(a, 0xa5, 512); + return 0; +} + +U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail, + "test stack protector fail", ""); diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9ba1..5a053c7336 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,23 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR + bool "Stack Protector buffer overflow detection" + default n + help + Enable stack smash detection through gcc built-in stack-protector + canary logic + +config SPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for SPL" + depends on STACKPROTECTOR && SPL + default n + +config TPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for TPL" + depends on STACKPROTECTOR && TPL + default n + endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d016..fe71e18317 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o + diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000000..014257b3e7 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> +#include <console.h> + +DECLARE_GLOBAL_DATA_PTR; + +unsigned long __stack_chk_guard = (long)(0xfeedf00ddeadbeef & ~0L); + +void __stack_chk_fail(void) +{ + panic("Stack smashing detected in function: %p relocated from %p", + __builtin_return_address(0), + __builtin_return_address(0) - gd->reloc_off); +} diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index f1ec701a9f..3e92a58bdb 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -274,3 +274,5 @@ CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y +CONFIG_STACKPROTECTOR=y +CONFIG_CMD_STACKPROTECTOR_TEST=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 9f1f7445d7..1505e4e851 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -63,6 +63,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif + # FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000000..957a2a6cf7 --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom + +import pytest +import signal + +@pytest.mark.buildconfigspec('cmd_stackprotector_test') +def test_stackprotector(u_boot_console): + """Test that the stackprotector function works.""" + + u_boot_console.run_command('stackprot_test',wait_for_prompt=False) + expected_response = 'Stack smashing detected' + u_boot_console.wait_for(expected_response) + assert(True) +
On 11.01.21 17:20, Joel Peshkin wrote:
Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Cc: Jagan Teki jagan@amarulasolutions.com Cc: Kever Yang kever.yang@rock-chips.com Cc: Heinrich Schuchardt xypron.glpk@gmx.de Cc: AKASHI Takahiro takahiro.akashi@linaro.org Cc: Usama Arif usama.arif@arm.com Cc: Sam Protsenko joe.skb7@gmail.com Cc: Masahiro Yamada masahiroy@kernel.org Cc: Philippe Reynes philippe.reynes@softathome.com Cc: Eugeniu Rosca roscaeugeniu@gmail.com Cc: Jan Kiszka jan.kiszka@siemens.com
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
Changes for v3:
- Move test command to cmd/
- Update Kconfig names and depends
- clean up default canary initialization
Changes for v2:
- Add test command and corresponding config
- Fixed incorrect description in Kconfig
- Add unit test
MAINTAINERS | 7 +++++++ Makefile | 4 ++++ cmd/Kconfig | 10 ++++++++++ cmd/Makefile | 1 + cmd/stackprot_test.c | 26 ++++++++++++++++++++++++++ common/Kconfig | 17 +++++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 18 ++++++++++++++++++ configs/sandbox_defconfig | 2 ++ scripts/Makefile.spl | 6 ++++++
Thanks for resubmitting.
I am missing the changes for lib/efi_loader/Makefile and lib/efi_selftest/Makefile to keep the stack protector out of the EFI binaries.
test/py/tests/test_stackprotector.py | 15 +++++++++++++++ 11 files changed, 108 insertions(+) create mode 100644 cmd/stackprot_test.c create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/MAINTAINERS b/MAINTAINERS index 52d7307525..2982ffcc07 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1022,6 +1022,13 @@ F: include/sqfs.h F: cmd/sqfs.c F: test/py/tests/test_fs/test_squashfs/
+STACKPROTECTOR +M: Joel Peshkin joel.peshkin@broadcom.com +S: Maintained +F: common/stackprot.c +F: cmd/stackprot_test.c +F: test/py/tests/test_stackprotector.py
TARGET_BCMNS3 M: Bharat Gooty bharat.gooty@broadcom.com M: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com diff --git a/Makefile b/Makefile index 3ee4cc00dd..6e7a81ec7d 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,11 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/cmd/Kconfig b/cmd/Kconfig index 1595de999b..04700e4bb4 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -2271,6 +2271,16 @@ config CMD_AVB avb read_part_hex - read data from partition and output to stdout avb write_part - write data to partition avb verify - run full verification chain
+config CMD_STACKPROTECTOR_TEST
- bool "Test command for stack protector"
- depends on STACKPROTECTOR
- default n
- help
Enable stackprot_test commandThe stackprot_test command will force a stack overrun to testthe stack smashing detection mechanisms.endmenu
config CMD_UBI diff --git a/cmd/Makefile b/cmd/Makefile index dd86675bf2..8e8fcea19e 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o obj-$(CONFIG_CMD_STRINGS) += strings.o obj-$(CONFIG_CMD_SMC) += smccc.o obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o obj-$(CONFIG_CMD_TERMINAL) += terminal.o obj-$(CONFIG_CMD_TIME) += time.o obj-$(CONFIG_CMD_TIMER) += timer.o diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c new file mode 100644 index 0000000000..ea952c075e --- /dev/null +++ b/cmd/stackprot_test.c @@ -0,0 +1,26 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021 Broadcom
- */
+#include <common.h> +#include <cli.h>
The include is not needed and should be removed.
+#include <command.h> +#include <console.h>
superfluous include
+DECLARE_GLOBAL_DATA_PTR;
+static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[]);
superfluous forward declaration
+int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc,
The static keyword can be added here.
Static is preferable. The only good thing about making it non-static would be easy checking if the address output works. Looks good at first sight:
Stack smashing detected for function: 00005591a897ea34 relocated from 000000000004ba34
u-boot.map: 0x000000000004b9ee do_test_stackprot_fail 0x000000000004befc print_byte_string
char *const argv[])+{
- char a[128];
- memset(a, 0xa5, 512);
- return 0;
+}
+U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail,
"test stack protector fail", "");diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9ba1..5a053c7336 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,23 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR
- bool "Stack Protector buffer overflow detection"
- default n
- help
Enable stack smash detection through gcc built-in stack-protector
We build U-Boot with Clang too. So I would prefer not to reference any individual compiler here.
GCC would have to be capitalized.
canary logic+config SPL_STACKPROTECTOR
- bool "Stack Protector buffer overflow detection for SPL"
- depends on STACKPROTECTOR && SPL
- default n
+config TPL_STACKPROTECTOR
- bool "Stack Protector buffer overflow detection for TPL"
- depends on STACKPROTECTOR && TPL
- default n
endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d016..fe71e18317 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o
diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000000..014257b3e7 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021 Broadcom
- */
+#include <common.h> +#include <console.h>
superfluous include
+DECLARE_GLOBAL_DATA_PTR;
+unsigned long __stack_chk_guard = (long)(0xfeedf00ddeadbeef & ~0L);
+void __stack_chk_fail(void) +{
- panic("Stack smashing detected in function: %p relocated from %p",
On a 64-bit system the current output does not fit into 80 characters. Please add a newline after the colon.
__builtin_return_address(0),
Shouldn't you use
__builtin_extract_return_addr(__builtin_return_address(0));
For instance on ARM6 condition codes may have to be masked out of the return address.
Cf. https://gcc.gnu.org/onlinedocs/gcc/Return-Address.html https://github.com/gcc-mirror/gcc/blob/master/gcc/config/arm/arm.h#L2316
Best regards
Heinrich
__builtin_return_address(0) - gd->reloc_off);+} diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index f1ec701a9f..3e92a58bdb 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -274,3 +274,5 @@ CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y +CONFIG_STACKPROTECTOR=y +CONFIG_CMD_STACKPROTECTOR_TEST=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 9f1f7445d7..1505e4e851 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -63,6 +63,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif
# FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000000..957a2a6cf7 --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom
+import pytest +import signal
+@pytest.mark.buildconfigspec('cmd_stackprotector_test') +def test_stackprotector(u_boot_console):
- """Test that the stackprotector function works."""
- u_boot_console.run_command('stackprot_test',wait_for_prompt=False)
- expected_response = 'Stack smashing detected'
- u_boot_console.wait_for(expected_response)
- assert(True)
Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Cc: Jagan Teki jagan@amarulasolutions.com Cc: Kever Yang kever.yang@rock-chips.com Cc: Heinrich Schuchardt xypron.glpk@gmx.de Cc: AKASHI Takahiro takahiro.akashi@linaro.org Cc: Usama Arif usama.arif@arm.com Cc: Sam Protsenko joe.skb7@gmail.com Cc: Masahiro Yamada masahiroy@kernel.org Cc: Philippe Reynes philippe.reynes@softathome.com Cc: Eugeniu Rosca roscaeugeniu@gmail.com Cc: Jan Kiszka jan.kiszka@siemens.com
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
Changes for v4: - Exclude EFI from stackprotector - Cleanups of extra includes and declaration
Changes for v3: - Move test command to cmd/ - Update Kconfig names and depends - clean up default canary initialization
Changes for v2: - Add test command and corresponding config - Fixed incorrect description in Kconfig - Add unit test --- MAINTAINERS | 7 +++++++ Makefile | 5 +++++ cmd/Kconfig | 10 ++++++++++ cmd/Makefile | 1 + cmd/stackprot_test.c | 21 +++++++++++++++++++++ common/Kconfig | 17 +++++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 17 +++++++++++++++++ configs/sandbox_defconfig | 2 ++ scripts/Makefile.spl | 6 ++++++ test/py/tests/test_stackprotector.py | 15 +++++++++++++++ 11 files changed, 103 insertions(+) create mode 100644 cmd/stackprot_test.c create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/MAINTAINERS b/MAINTAINERS index 52d7307525..2982ffcc07 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1022,6 +1022,13 @@ F: include/sqfs.h F: cmd/sqfs.c F: test/py/tests/test_fs/test_squashfs/
+STACKPROTECTOR +M: Joel Peshkin joel.peshkin@broadcom.com +S: Maintained +F: common/stackprot.c +F: cmd/stackprot_test.c +F: test/py/tests/test_stackprotector.py + TARGET_BCMNS3 M: Bharat Gooty bharat.gooty@broadcom.com M: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com diff --git a/Makefile b/Makefile index 3ee4cc00dd..8c04fcf96c 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,12 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +CFLAGS_EFI += $(call cc-option,-fno-stack-protector) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/cmd/Kconfig b/cmd/Kconfig index 1595de999b..04700e4bb4 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -2271,6 +2271,16 @@ config CMD_AVB avb read_part_hex - read data from partition and output to stdout avb write_part - write data to partition avb verify - run full verification chain + +config CMD_STACKPROTECTOR_TEST + bool "Test command for stack protector" + depends on STACKPROTECTOR + default n + help + Enable stackprot_test command + The stackprot_test command will force a stack overrun to test + the stack smashing detection mechanisms. + endmenu
config CMD_UBI diff --git a/cmd/Makefile b/cmd/Makefile index dd86675bf2..8e8fcea19e 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o obj-$(CONFIG_CMD_STRINGS) += strings.o obj-$(CONFIG_CMD_SMC) += smccc.o obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o obj-$(CONFIG_CMD_TERMINAL) += terminal.o obj-$(CONFIG_CMD_TIME) += time.o obj-$(CONFIG_CMD_TIMER) += timer.o diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c new file mode 100644 index 0000000000..6ad287e55f --- /dev/null +++ b/cmd/stackprot_test.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> +#include <command.h> + +DECLARE_GLOBAL_DATA_PTR; + +static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + char a[128]; + + memset(a, 0xa5, 512); + return 0; +} + +U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail, + "test stack protector fail", ""); diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9ba1..6a94045948 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,23 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR + bool "Stack Protector buffer overflow detection" + default n + help + Enable stack smash detection through compiler's stack-protector + canary logic + +config SPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for SPL" + depends on STACKPROTECTOR && SPL + default n + +config TPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for TPL" + depends on STACKPROTECTOR && TPL + default n + endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d016..fe71e18317 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o + diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000000..1f1c3b4273 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> + +DECLARE_GLOBAL_DATA_PTR; + +unsigned long __stack_chk_guard = (long)(0xfeedf00ddeadbeef & ~0L); + +void __stack_chk_fail(void) +{ + panic("Stack smashing detected in function:\n%p relocated from %p", + __builtin_extract_return_addr(__builtin_return_address(0)), + __builtin_return_address(0) - gd->reloc_off); +} diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index f1ec701a9f..3e92a58bdb 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -274,3 +274,5 @@ CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y +CONFIG_STACKPROTECTOR=y +CONFIG_CMD_STACKPROTECTOR_TEST=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 9f1f7445d7..1505e4e851 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -63,6 +63,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif + # FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000000..957a2a6cf7 --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom + +import pytest +import signal + +@pytest.mark.buildconfigspec('cmd_stackprotector_test') +def test_stackprotector(u_boot_console): + """Test that the stackprotector function works.""" + + u_boot_console.run_command('stackprot_test',wait_for_prompt=False) + expected_response = 'Stack smashing detected' + u_boot_console.wait_for(expected_response) + assert(True) +
On 11.01.21 23:49, Joel Peshkin wrote:
Somehow the commit message got lost.
Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com Cc: Jagan Teki jagan@amarulasolutions.com Cc: Kever Yang kever.yang@rock-chips.com Cc: Heinrich Schuchardt xypron.glpk@gmx.de Cc: AKASHI Takahiro takahiro.akashi@linaro.org Cc: Usama Arif usama.arif@arm.com Cc: Sam Protsenko joe.skb7@gmail.com Cc: Masahiro Yamada masahiroy@kernel.org Cc: Philippe Reynes philippe.reynes@softathome.com Cc: Eugeniu Rosca roscaeugeniu@gmail.com Cc: Jan Kiszka jan.kiszka@siemens.com
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
Changes for v4:
- Exclude EFI from stackprotector
I cannot find this in the code below.
The safest thing to do is to add a __stack_chk_fail() function to lib/efi_loader/efi_freestanding.c:
void __stack_chk_fail(void) { for (;;) ; }
- Cleanups of extra includes and declaration
Changes for v3:
- Move test command to cmd/
- Update Kconfig names and depends
- clean up default canary initialization
Changes for v2:
- Add test command and corresponding config
- Fixed incorrect description in Kconfig
- Add unit test
MAINTAINERS | 7 +++++++ Makefile | 5 +++++ cmd/Kconfig | 10 ++++++++++ cmd/Makefile | 1 + cmd/stackprot_test.c | 21 +++++++++++++++++++++ common/Kconfig | 17 +++++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 17 +++++++++++++++++ configs/sandbox_defconfig | 2 ++ scripts/Makefile.spl | 6 ++++++ test/py/tests/test_stackprotector.py | 15 +++++++++++++++ 11 files changed, 103 insertions(+) create mode 100644 cmd/stackprot_test.c create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/MAINTAINERS b/MAINTAINERS index 52d7307525..2982ffcc07 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1022,6 +1022,13 @@ F: include/sqfs.h F: cmd/sqfs.c F: test/py/tests/test_fs/test_squashfs/
+STACKPROTECTOR +M: Joel Peshkin joel.peshkin@broadcom.com +S: Maintained +F: common/stackprot.c +F: cmd/stackprot_test.c +F: test/py/tests/test_stackprotector.py
TARGET_BCMNS3 M: Bharat Gooty bharat.gooty@broadcom.com M: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com diff --git a/Makefile b/Makefile index 3ee4cc00dd..8c04fcf96c 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,12 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +CFLAGS_EFI += $(call cc-option,-fno-stack-protector) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/cmd/Kconfig b/cmd/Kconfig index 1595de999b..04700e4bb4 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -2271,6 +2271,16 @@ config CMD_AVB avb read_part_hex - read data from partition and output to stdout avb write_part - write data to partition avb verify - run full verification chain
+config CMD_STACKPROTECTOR_TEST
- bool "Test command for stack protector"
- depends on STACKPROTECTOR
- default n
- help
Enable stackprot_test commandThe stackprot_test command will force a stack overrun to testthe stack smashing detection mechanisms.endmenu
config CMD_UBI diff --git a/cmd/Makefile b/cmd/Makefile index dd86675bf2..8e8fcea19e 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o obj-$(CONFIG_CMD_STRINGS) += strings.o obj-$(CONFIG_CMD_SMC) += smccc.o obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o obj-$(CONFIG_CMD_TERMINAL) += terminal.o obj-$(CONFIG_CMD_TIME) += time.o obj-$(CONFIG_CMD_TIMER) += timer.o diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c new file mode 100644 index 0000000000..6ad287e55f --- /dev/null +++ b/cmd/stackprot_test.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021 Broadcom
- */
+#include <common.h> +#include <command.h>
+DECLARE_GLOBAL_DATA_PTR;
+static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])+{
- char a[128];
- memset(a, 0xa5, 512);
- return 0;
+}
+U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail,
"test stack protector fail", "");diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9ba1..6a94045948 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,23 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR
- bool "Stack Protector buffer overflow detection"
- default n
- help
Enable stack smash detection through compiler's stack-protectorcanary logic+config SPL_STACKPROTECTOR
- bool "Stack Protector buffer overflow detection for SPL"
- depends on STACKPROTECTOR && SPL
- default n
+config TPL_STACKPROTECTOR
- bool "Stack Protector buffer overflow detection for TPL"
- depends on STACKPROTECTOR && TPL
- default n
endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d016..fe71e18317 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o
diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000000..1f1c3b4273 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021 Broadcom
- */
+#include <common.h>
+DECLARE_GLOBAL_DATA_PTR;
+unsigned long __stack_chk_guard = (long)(0xfeedf00ddeadbeef & ~0L);
+void __stack_chk_fail(void) +{
- panic("Stack smashing detected in function:\n%p relocated from %p",
__builtin_extract_return_addr(__builtin_return_address(0)),__builtin_return_address(0) - gd->reloc_off);
Missing __builtin_extract_return_addr(). I suggest you add a line
void *addr = __builtin_extract_return_addr(__builtin_return_address(0));
and then use that variable for the panic() call.
+} diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index f1ec701a9f..3e92a58bdb 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -274,3 +274,5 @@ CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y +CONFIG_STACKPROTECTOR=y +CONFIG_CMD_STACKPROTECTOR_TEST=y
Please, use make safedefconfig to get the sequence right. If there are too many unrelated changes, you can split of a separate patch for realigning sandbox_defconfig first.
Best regards
Heinrich
diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 9f1f7445d7..1505e4e851 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -63,6 +63,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif
# FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000000..957a2a6cf7 --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom
+import pytest +import signal
+@pytest.mark.buildconfigspec('cmd_stackprotector_test') +def test_stackprotector(u_boot_console):
- """Test that the stackprotector function works."""
- u_boot_console.run_command('stackprot_test',wait_for_prompt=False)
- expected_response = 'Stack smashing detected'
- u_boot_console.wait_for(expected_response)
- assert(True)
Cc: Joel Peshkin joel.peshkin@broadcom.com, Simon Glass sjg@chromium.org, Bin Meng bmeng.cn@gmail.com, Jagan Teki jagan@amarulasolutions.com, Kever Yang kever.yang@rock-chips.com, Heinrich Schuchardt xypron.glpk@gmx.de, AKASHI Takahiro takahiro.akashi@linaro.org, Usama Arif usama.arif@arm.com, Sam Protsenko joe.skb7@gmail.com, Masahiro Yamada masahiroy@kernel.org, Philippe Reynes philippe.reynes@softathome.com, Eugeniu Rosca roscaeugeniu@gmail.com, Jan Kiszka jan.kiszka@siemens.com Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
Changes for v5: - Rebase Changes for v4: - Exclude EFI from stackprotector - Cleanups of extra includes and declaration
Changes for v3: - Move test command to cmd/ - Update Kconfig names and depends - clean up default canary initialization
Changes for v2: - Add test command and corresponding config - Fixed incorrect description in Kconfig - Add unit test --- --- MAINTAINERS | 7 +++++++ Makefile | 5 +++++ cmd/Kconfig | 10 ++++++++++ cmd/Makefile | 1 + cmd/stackprot_test.c | 21 +++++++++++++++++++++ common/Kconfig | 17 +++++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 17 +++++++++++++++++ configs/sandbox_defconfig | 14 +++++++------- scripts/Makefile.spl | 6 ++++++ test/py/tests/test_stackprotector.py | 15 +++++++++++++++ 11 files changed, 108 insertions(+), 7 deletions(-) create mode 100644 cmd/stackprot_test.c create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/MAINTAINERS b/MAINTAINERS index 26dd254..d3971e8 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1024,6 +1024,13 @@ F: include/sqfs.h F: cmd/sqfs.c F: test/py/tests/test_fs/test_squashfs/
+STACKPROTECTOR +M: Joel Peshkin joel.peshkin@broadcom.com +S: Maintained +F: common/stackprot.c +F: cmd/stackprot_test.c +F: test/py/tests/test_stackprotector.py + TARGET_BCMNS3 M: Bharat Gooty bharat.gooty@broadcom.com M: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com diff --git a/Makefile b/Makefile index 902a976..65c5cb8 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,12 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +CFLAGS_EFI += $(call cc-option,-fno-stack-protector) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/cmd/Kconfig b/cmd/Kconfig index da86a94..054b2f3 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -2280,6 +2280,16 @@ config CMD_AVB avb read_part_hex - read data from partition and output to stdout avb write_part - write data to partition avb verify - run full verification chain + +config CMD_STACKPROTECTOR_TEST + bool "Test command for stack protector" + depends on STACKPROTECTOR + default n + help + Enable stackprot_test command + The stackprot_test command will force a stack overrun to test + the stack smashing detection mechanisms. + endmenu
config CMD_UBI diff --git a/cmd/Makefile b/cmd/Makefile index 5b3400a..1d7afea 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o obj-$(CONFIG_CMD_STRINGS) += strings.o obj-$(CONFIG_CMD_SMC) += smccc.o obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o obj-$(CONFIG_CMD_TERMINAL) += terminal.o obj-$(CONFIG_CMD_TIME) += time.o obj-$(CONFIG_CMD_TIMER) += timer.o diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c new file mode 100644 index 0000000..6ad287e --- /dev/null +++ b/cmd/stackprot_test.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> +#include <command.h> + +DECLARE_GLOBAL_DATA_PTR; + +static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + char a[128]; + + memset(a, 0xa5, 512); + return 0; +} + +U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail, + "test stack protector fail", ""); diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9..6a94045 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,23 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR + bool "Stack Protector buffer overflow detection" + default n + help + Enable stack smash detection through compiler's stack-protector + canary logic + +config SPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for SPL" + depends on STACKPROTECTOR && SPL + default n + +config TPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for TPL" + depends on STACKPROTECTOR && TPL + default n + endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d..fe71e18 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o + diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000..1f1c3b4 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> + +DECLARE_GLOBAL_DATA_PTR; + +unsigned long __stack_chk_guard = (long)(0xfeedf00ddeadbeef & ~0L); + +void __stack_chk_fail(void) +{ + panic("Stack smashing detected in function:\n%p relocated from %p", + __builtin_extract_return_addr(__builtin_return_address(0)), + __builtin_return_address(0) - gd->reloc_off); +} diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index 58d4ef1..0c82ef2 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -20,11 +20,11 @@ CONFIG_BOOTSTAGE_STASH=y CONFIG_BOOTSTAGE_STASH_SIZE=0x4096 CONFIG_CONSOLE_RECORD=y CONFIG_CONSOLE_RECORD_OUT_SIZE=0x1000 -CONFIG_SILENT_CONSOLE=y CONFIG_PRE_CONSOLE_BUFFER=y CONFIG_LOG_SYSLOG=y CONFIG_LOG_ERROR_RETURN=y CONFIG_DISPLAY_BOARDINFO_LATE=y +CONFIG_STACKPROTECTOR=y CONFIG_ANDROID_AB=y CONFIG_CMD_CPU=y CONFIG_CMD_LICENSE=y @@ -96,6 +96,7 @@ CONFIG_CMD_CRAMFS=y CONFIG_CMD_EXT4_WRITE=y CONFIG_CMD_SQUASHFS=y CONFIG_CMD_MTDPARTS=y +CONFIG_CMD_STACKPROTECTOR_TEST=y CONFIG_MAC_PARTITION=y CONFIG_AMIGA_PARTITION=y CONFIG_OF_CONTROL=y @@ -131,6 +132,7 @@ CONFIG_CPU=y CONFIG_DM_DEMO=y CONFIG_DM_DEMO_SIMPLE=y CONFIG_DM_DEMO_SHAPE=y +CONFIG_DFU_SF=y CONFIG_DMA=y CONFIG_DMA_CHANNELS=y CONFIG_SANDBOX_DMA=y @@ -269,14 +271,12 @@ CONFIG_CMD_DHRYSTONE=y CONFIG_TPM=y CONFIG_LZ4=y CONFIG_ERRNO_STR=y +CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y +CONFIG_EFI_CAPSULE_ON_DISK=y +CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y +CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y CONFIG_EFI_SECURE_BOOT=y CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y -# -CONFIG_DFU_SF=y -CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y -CONFIG_EFI_CAPSULE_ON_DISK=y -CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y -CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 87021e2..6725201 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -67,6 +67,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif + # FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000..957a2a6 --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom + +import pytest +import signal + +@pytest.mark.buildconfigspec('cmd_stackprotector_test') +def test_stackprotector(u_boot_console): + """Test that the stackprotector function works.""" + + u_boot_console.run_command('stackprot_test',wait_for_prompt=False) + expected_response = 'Stack smashing detected' + u_boot_console.wait_for(expected_response) + assert(True) +
Cc: Simon Glass sjg@chromium.org Cc: Heinrich Schuchardt xypron.glpk@gmx.de Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
Changes for v6: - Fix commit message Changes for v5: - Rebase Changes for v4: - Exclude EFI from stackprotector - Cleanups of extra includes and declaration Changes for v3: - Move test command to cmd/ - Update Kconfig names and depends - clean up default canary initialization Changes for v2: - Add test command and corresponding config - Fixed incorrect description in Kconfig - Add unit test --- --- MAINTAINERS | 7 +++++++ Makefile | 5 +++++ cmd/Kconfig | 10 ++++++++++ cmd/Makefile | 1 + cmd/stackprot_test.c | 21 +++++++++++++++++++++ common/Kconfig | 17 +++++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 17 +++++++++++++++++ configs/sandbox_defconfig | 14 +++++++------- scripts/Makefile.spl | 6 ++++++ test/py/tests/test_stackprotector.py | 15 +++++++++++++++ 11 files changed, 108 insertions(+), 7 deletions(-) create mode 100644 cmd/stackprot_test.c create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/MAINTAINERS b/MAINTAINERS index 26dd254..d3971e8 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1024,6 +1024,13 @@ F: include/sqfs.h F: cmd/sqfs.c F: test/py/tests/test_fs/test_squashfs/
+STACKPROTECTOR +M: Joel Peshkin joel.peshkin@broadcom.com +S: Maintained +F: common/stackprot.c +F: cmd/stackprot_test.c +F: test/py/tests/test_stackprotector.py + TARGET_BCMNS3 M: Bharat Gooty bharat.gooty@broadcom.com M: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com diff --git a/Makefile b/Makefile index 902a976..65c5cb8 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,12 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +CFLAGS_EFI += $(call cc-option,-fno-stack-protector) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/cmd/Kconfig b/cmd/Kconfig index da86a94..054b2f3 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -2280,6 +2280,16 @@ config CMD_AVB avb read_part_hex - read data from partition and output to stdout avb write_part - write data to partition avb verify - run full verification chain + +config CMD_STACKPROTECTOR_TEST + bool "Test command for stack protector" + depends on STACKPROTECTOR + default n + help + Enable stackprot_test command + The stackprot_test command will force a stack overrun to test + the stack smashing detection mechanisms. + endmenu
config CMD_UBI diff --git a/cmd/Makefile b/cmd/Makefile index 5b3400a..1d7afea 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o obj-$(CONFIG_CMD_STRINGS) += strings.o obj-$(CONFIG_CMD_SMC) += smccc.o obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o obj-$(CONFIG_CMD_TERMINAL) += terminal.o obj-$(CONFIG_CMD_TIME) += time.o obj-$(CONFIG_CMD_TIMER) += timer.o diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c new file mode 100644 index 0000000..6ad287e --- /dev/null +++ b/cmd/stackprot_test.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> +#include <command.h> + +DECLARE_GLOBAL_DATA_PTR; + +static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + char a[128]; + + memset(a, 0xa5, 512); + return 0; +} + +U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail, + "test stack protector fail", ""); diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9..6a94045 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,23 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR + bool "Stack Protector buffer overflow detection" + default n + help + Enable stack smash detection through compiler's stack-protector + canary logic + +config SPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for SPL" + depends on STACKPROTECTOR && SPL + default n + +config TPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for TPL" + depends on STACKPROTECTOR && TPL + default n + endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d..fe71e18 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o + diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000..1f1c3b4 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> + +DECLARE_GLOBAL_DATA_PTR; + +unsigned long __stack_chk_guard = (long)(0xfeedf00ddeadbeef & ~0L); + +void __stack_chk_fail(void) +{ + panic("Stack smashing detected in function:\n%p relocated from %p", + __builtin_extract_return_addr(__builtin_return_address(0)), + __builtin_return_address(0) - gd->reloc_off); +} diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index 58d4ef1..0c82ef2 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -20,11 +20,11 @@ CONFIG_BOOTSTAGE_STASH=y CONFIG_BOOTSTAGE_STASH_SIZE=0x4096 CONFIG_CONSOLE_RECORD=y CONFIG_CONSOLE_RECORD_OUT_SIZE=0x1000 -CONFIG_SILENT_CONSOLE=y CONFIG_PRE_CONSOLE_BUFFER=y CONFIG_LOG_SYSLOG=y CONFIG_LOG_ERROR_RETURN=y CONFIG_DISPLAY_BOARDINFO_LATE=y +CONFIG_STACKPROTECTOR=y CONFIG_ANDROID_AB=y CONFIG_CMD_CPU=y CONFIG_CMD_LICENSE=y @@ -96,6 +96,7 @@ CONFIG_CMD_CRAMFS=y CONFIG_CMD_EXT4_WRITE=y CONFIG_CMD_SQUASHFS=y CONFIG_CMD_MTDPARTS=y +CONFIG_CMD_STACKPROTECTOR_TEST=y CONFIG_MAC_PARTITION=y CONFIG_AMIGA_PARTITION=y CONFIG_OF_CONTROL=y @@ -131,6 +132,7 @@ CONFIG_CPU=y CONFIG_DM_DEMO=y CONFIG_DM_DEMO_SIMPLE=y CONFIG_DM_DEMO_SHAPE=y +CONFIG_DFU_SF=y CONFIG_DMA=y CONFIG_DMA_CHANNELS=y CONFIG_SANDBOX_DMA=y @@ -269,14 +271,12 @@ CONFIG_CMD_DHRYSTONE=y CONFIG_TPM=y CONFIG_LZ4=y CONFIG_ERRNO_STR=y +CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y +CONFIG_EFI_CAPSULE_ON_DISK=y +CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y +CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y CONFIG_EFI_SECURE_BOOT=y CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y -# -CONFIG_DFU_SF=y -CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y -CONFIG_EFI_CAPSULE_ON_DISK=y -CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y -CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 87021e2..6725201 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -67,6 +67,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif + # FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000..957a2a6 --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom + +import pytest +import signal + +@pytest.mark.buildconfigspec('cmd_stackprotector_test') +def test_stackprotector(u_boot_console): + """Test that the stackprotector function works.""" + + u_boot_console.run_command('stackprot_test',wait_for_prompt=False) + expected_response = 'Stack smashing detected' + u_boot_console.wait_for(expected_response) + assert(True) +
On 12.01.21 17:51, Joel Peshkin wrote:> Cc: Simon Glass sjg@chromium.org> Cc: Heinrich Schuchardt xypron.glpk@gmx.de> Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com These lines should be below the commit message body.
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
The following lines should be below the first ---.
Changes for v6:
- Fix commit message
Changes for v5:
- Rebase
Changes for v4:
- Exclude EFI from stackprotector
- Cleanups of extra includes and declaration
Changes for v3:
- Move test command to cmd/
- Update Kconfig names and depends
- clean up default canary initialization
Changes for v2:
- Add test command and corresponding config
- Fixed incorrect description in Kconfig
- Add unit test
MAINTAINERS | 7 +++++++ Makefile | 5 +++++ cmd/Kconfig | 10 ++++++++++ cmd/Makefile | 1 + cmd/stackprot_test.c | 21 +++++++++++++++++++++ common/Kconfig | 17 +++++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 17 +++++++++++++++++ configs/sandbox_defconfig | 14 +++++++------- scripts/Makefile.spl | 6 ++++++ test/py/tests/test_stackprotector.py | 15 +++++++++++++++ 11 files changed, 108 insertions(+), 7 deletions(-) create mode 100644 cmd/stackprot_test.c create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/MAINTAINERS b/MAINTAINERS index 26dd254..d3971e8 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1024,6 +1024,13 @@ F: include/sqfs.h F: cmd/sqfs.c F: test/py/tests/test_fs/test_squashfs/
+STACKPROTECTOR +M: Joel Peshkin joel.peshkin@broadcom.com +S: Maintained +F: common/stackprot.c +F: cmd/stackprot_test.c +F: test/py/tests/test_stackprotector.py
TARGET_BCMNS3 M: Bharat Gooty bharat.gooty@broadcom.com M: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com diff --git a/Makefile b/Makefile index 902a976..65c5cb8 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,12 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +CFLAGS_EFI += $(call cc-option,-fno-stack-protector) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/cmd/Kconfig b/cmd/Kconfig index da86a94..054b2f3 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -2280,6 +2280,16 @@ config CMD_AVB avb read_part_hex - read data from partition and output to stdout avb write_part - write data to partition avb verify - run full verification chain
+config CMD_STACKPROTECTOR_TEST
- bool "Test command for stack protector"
- depends on STACKPROTECTOR
- default n
- help
Enable stackprot_test commandThe stackprot_test command will force a stack overrun to testthe stack smashing detection mechanisms.endmenu
config CMD_UBI diff --git a/cmd/Makefile b/cmd/Makefile index 5b3400a..1d7afea 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o obj-$(CONFIG_CMD_STRINGS) += strings.o obj-$(CONFIG_CMD_SMC) += smccc.o obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o obj-$(CONFIG_CMD_TERMINAL) += terminal.o obj-$(CONFIG_CMD_TIME) += time.o obj-$(CONFIG_CMD_TIMER) += timer.o diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c new file mode 100644 index 0000000..6ad287e --- /dev/null +++ b/cmd/stackprot_test.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021 Broadcom
- */
+#include <common.h> +#include <command.h>
+DECLARE_GLOBAL_DATA_PTR;
+static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])+{
- char a[128];
- memset(a, 0xa5, 512);
- return 0;
+}
+U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail,
"test stack protector fail", "");diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9..6a94045 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,23 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR
- bool "Stack Protector buffer overflow detection"
- default n
- help
Enable stack smash detection through compiler's stack-protectorcanary logic+config SPL_STACKPROTECTOR
- bool "Stack Protector buffer overflow detection for SPL"
- depends on STACKPROTECTOR && SPL
- default n
+config TPL_STACKPROTECTOR
- bool "Stack Protector buffer overflow detection for TPL"
- depends on STACKPROTECTOR && TPL
- default n
endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d..fe71e18 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o
diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000..1f1c3b4 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021 Broadcom
- */
+#include <common.h>
+DECLARE_GLOBAL_DATA_PTR;
+unsigned long __stack_chk_guard = (long)(0xfeedf00ddeadbeef & ~0L);
+void __stack_chk_fail(void) +{
- panic("Stack smashing detected in function:\n%p relocated from %p",
__builtin_extract_return_addr(__builtin_return_address(0)),__builtin_return_address(0) - gd->reloc_off);
A __builtin_extract_return_addr() is missing here.
I suggest that you first write __builtin_extract_return_addr(__builtin_return_address(0)) into a variable and than use it in panic().
Best regards
Heinrich
+} diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index 58d4ef1..0c82ef2 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -20,11 +20,11 @@ CONFIG_BOOTSTAGE_STASH=y CONFIG_BOOTSTAGE_STASH_SIZE=0x4096 CONFIG_CONSOLE_RECORD=y CONFIG_CONSOLE_RECORD_OUT_SIZE=0x1000 -CONFIG_SILENT_CONSOLE=y CONFIG_PRE_CONSOLE_BUFFER=y CONFIG_LOG_SYSLOG=y CONFIG_LOG_ERROR_RETURN=y CONFIG_DISPLAY_BOARDINFO_LATE=y +CONFIG_STACKPROTECTOR=y CONFIG_ANDROID_AB=y CONFIG_CMD_CPU=y CONFIG_CMD_LICENSE=y @@ -96,6 +96,7 @@ CONFIG_CMD_CRAMFS=y CONFIG_CMD_EXT4_WRITE=y CONFIG_CMD_SQUASHFS=y CONFIG_CMD_MTDPARTS=y +CONFIG_CMD_STACKPROTECTOR_TEST=y CONFIG_MAC_PARTITION=y CONFIG_AMIGA_PARTITION=y CONFIG_OF_CONTROL=y @@ -131,6 +132,7 @@ CONFIG_CPU=y CONFIG_DM_DEMO=y CONFIG_DM_DEMO_SIMPLE=y CONFIG_DM_DEMO_SHAPE=y +CONFIG_DFU_SF=y CONFIG_DMA=y CONFIG_DMA_CHANNELS=y CONFIG_SANDBOX_DMA=y @@ -269,14 +271,12 @@ CONFIG_CMD_DHRYSTONE=y CONFIG_TPM=y CONFIG_LZ4=y CONFIG_ERRNO_STR=y +CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y +CONFIG_EFI_CAPSULE_ON_DISK=y +CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y +CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y CONFIG_EFI_SECURE_BOOT=y CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y -# -CONFIG_DFU_SF=y -CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y -CONFIG_EFI_CAPSULE_ON_DISK=y -CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y -CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 87021e2..6725201 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -67,6 +67,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif
# FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000..957a2a6 --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom
+import pytest +import signal
+@pytest.mark.buildconfigspec('cmd_stackprotector_test') +def test_stackprotector(u_boot_console):
- """Test that the stackprotector function works."""
- u_boot_console.run_command('stackprot_test',wait_for_prompt=False)
- expected_response = 'Stack smashing detected'
- u_boot_console.wait_for(expected_response)
- assert(True)
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com Cc: Simon Glass sjg@chromium.org Cc: Heinrich Schuchardt xypron.glpk@gmx.de
Changes for v7: - Fix commit message - add __builtin_extract_return_addr() calls Changes for v6: - Fix commit message Changes for v5: - Rebase Changes for v4: - Exclude EFI from stackprotector - Cleanups of extra includes and declaration Changes for v3: - Move test command to cmd/ - Update Kconfig names and depends - clean up default canary initialization Changes for v2: - Add test command and corresponding config - Fixed incorrect description in Kconfig - Add unit test --- --- MAINTAINERS | 7 +++++++ Makefile | 5 +++++ cmd/Kconfig | 10 ++++++++++ cmd/Makefile | 1 + cmd/stackprot_test.c | 21 +++++++++++++++++++++ common/Kconfig | 17 +++++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 19 +++++++++++++++++++ configs/sandbox_defconfig | 14 +++++++------- scripts/Makefile.spl | 6 ++++++ test/py/tests/test_stackprotector.py | 15 +++++++++++++++ 11 files changed, 110 insertions(+), 7 deletions(-) create mode 100644 cmd/stackprot_test.c create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/MAINTAINERS b/MAINTAINERS index 26dd254..d3971e8 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1024,6 +1024,13 @@ F: include/sqfs.h F: cmd/sqfs.c F: test/py/tests/test_fs/test_squashfs/
+STACKPROTECTOR +M: Joel Peshkin joel.peshkin@broadcom.com +S: Maintained +F: common/stackprot.c +F: cmd/stackprot_test.c +F: test/py/tests/test_stackprotector.py + TARGET_BCMNS3 M: Bharat Gooty bharat.gooty@broadcom.com M: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com diff --git a/Makefile b/Makefile index 902a976..65c5cb8 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,12 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +CFLAGS_EFI += $(call cc-option,-fno-stack-protector) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/cmd/Kconfig b/cmd/Kconfig index da86a94..054b2f3 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -2280,6 +2280,16 @@ config CMD_AVB avb read_part_hex - read data from partition and output to stdout avb write_part - write data to partition avb verify - run full verification chain + +config CMD_STACKPROTECTOR_TEST + bool "Test command for stack protector" + depends on STACKPROTECTOR + default n + help + Enable stackprot_test command + The stackprot_test command will force a stack overrun to test + the stack smashing detection mechanisms. + endmenu
config CMD_UBI diff --git a/cmd/Makefile b/cmd/Makefile index 5b3400a..1d7afea 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o obj-$(CONFIG_CMD_STRINGS) += strings.o obj-$(CONFIG_CMD_SMC) += smccc.o obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o obj-$(CONFIG_CMD_TERMINAL) += terminal.o obj-$(CONFIG_CMD_TIME) += time.o obj-$(CONFIG_CMD_TIMER) += timer.o diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c new file mode 100644 index 0000000..6ad287e --- /dev/null +++ b/cmd/stackprot_test.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> +#include <command.h> + +DECLARE_GLOBAL_DATA_PTR; + +static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + char a[128]; + + memset(a, 0xa5, 512); + return 0; +} + +U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail, + "test stack protector fail", ""); diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9..6a94045 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,23 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR + bool "Stack Protector buffer overflow detection" + default n + help + Enable stack smash detection through compiler's stack-protector + canary logic + +config SPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for SPL" + depends on STACKPROTECTOR && SPL + default n + +config TPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for TPL" + depends on STACKPROTECTOR && TPL + default n + endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d..fe71e18 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o + diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000..d335946 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> + +DECLARE_GLOBAL_DATA_PTR; + +unsigned long __stack_chk_guard = (long)(0xfeedf00ddeadbeef & ~0L); + +void __stack_chk_fail(void) +{ + void *ra; + + ra = __builtin_extract_return_addr(__builtin_return_address(0)); + panic("Stack smashing detected in function:\n%p relocated from %p", + ra, ra - gd->reloc_off); +} diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index 58d4ef1..0c82ef2 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -20,11 +20,11 @@ CONFIG_BOOTSTAGE_STASH=y CONFIG_BOOTSTAGE_STASH_SIZE=0x4096 CONFIG_CONSOLE_RECORD=y CONFIG_CONSOLE_RECORD_OUT_SIZE=0x1000 -CONFIG_SILENT_CONSOLE=y CONFIG_PRE_CONSOLE_BUFFER=y CONFIG_LOG_SYSLOG=y CONFIG_LOG_ERROR_RETURN=y CONFIG_DISPLAY_BOARDINFO_LATE=y +CONFIG_STACKPROTECTOR=y CONFIG_ANDROID_AB=y CONFIG_CMD_CPU=y CONFIG_CMD_LICENSE=y @@ -96,6 +96,7 @@ CONFIG_CMD_CRAMFS=y CONFIG_CMD_EXT4_WRITE=y CONFIG_CMD_SQUASHFS=y CONFIG_CMD_MTDPARTS=y +CONFIG_CMD_STACKPROTECTOR_TEST=y CONFIG_MAC_PARTITION=y CONFIG_AMIGA_PARTITION=y CONFIG_OF_CONTROL=y @@ -131,6 +132,7 @@ CONFIG_CPU=y CONFIG_DM_DEMO=y CONFIG_DM_DEMO_SIMPLE=y CONFIG_DM_DEMO_SHAPE=y +CONFIG_DFU_SF=y CONFIG_DMA=y CONFIG_DMA_CHANNELS=y CONFIG_SANDBOX_DMA=y @@ -269,14 +271,12 @@ CONFIG_CMD_DHRYSTONE=y CONFIG_TPM=y CONFIG_LZ4=y CONFIG_ERRNO_STR=y +CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y +CONFIG_EFI_CAPSULE_ON_DISK=y +CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y +CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y CONFIG_EFI_SECURE_BOOT=y CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y -# -CONFIG_DFU_SF=y -CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y -CONFIG_EFI_CAPSULE_ON_DISK=y -CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y -CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 87021e2..6725201 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -67,6 +67,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif + # FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000..957a2a6 --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom + +import pytest +import signal + +@pytest.mark.buildconfigspec('cmd_stackprotector_test') +def test_stackprotector(u_boot_console): + """Test that the stackprotector function works.""" + + u_boot_console.run_command('stackprot_test',wait_for_prompt=False) + expected_response = 'Stack smashing detected' + u_boot_console.wait_for(expected_response) + assert(True) +
Dear Joel,
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com Cc: Simon Glass sjg@chromium.org Cc: Heinrich Schuchardt xypron.glpk@gmx.de
Changes for v7: - Fix commit message - add __builtin_extract_return_addr() calls Changes for v6: - Fix commit message Changes for v5: - Rebase Changes for v4: - Exclude EFI from stackprotector - Cleanups of extra includes and declaration Changes for v3: - Move test command to cmd/ - Update Kconfig names and depends - clean up default canary initialization Changes for v2: - Add test command and corresponding config - Fixed incorrect description in Kconfig - Add unit test
Patch changelog is not a part of commit message, it's placed below the '---' mark. I hope this guide will help you: https://www.denx.de/wiki/view/U-Boot/Patches#Sending_updated_patch_versions
[...] +DECLARE_GLOBAL_DATA_PTR;
+unsigned long __stack_chk_guard = (long)(0xfeedf00ddeadbeef & ~0L);
'long' and 'unsigned long' are slightly different types. I suggest you the following form (please, note the UL instead of L):
unsigned long __stack_chk_guard = (unsigned long)(0xfeedf00ddeadbeef & ~0UL)
Else gcc will complain like this:
warning: unsigned conversion from ‘long int’ to ‘long long unsigned int’ changes value from ‘-1’ to ‘18446744073709551615’ [-Wsign-conversion] unsigned long __stack_chk_guard = (long)(0xfeedf00ddeadbeef & ~0L); warning: unsigned conversion from ‘long int’ to ‘long unsigned int’ changes value from ‘-559038737’ to ‘3735928559’ [-Wsign-conversion]
I hope you'll find -Wconversion compiler flag useful, it's one of the flags that often help me to spot some corner cases with potential bugs. IMHO it should be enabled by default.
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com --- Cc: Simon Glass sjg@chromium.org Cc: Heinrich Schuchardt xypron.glpk@gmx.de
Changes for v8: - Fix commit message - Force canary to UL type Changes for v7: - Fix commit message - add __builtin_extract_return_addr() calls Changes for v6: - Fix commit message Changes for v5: - Rebase Changes for v4: - Exclude EFI from stackprotector - Cleanups of extra includes and declaration Changes for v3: - Move test command to cmd/ - Update Kconfig names and depends - clean up default canary initialization Changes for v2: - Add test command and corresponding config - Fixed incorrect description in Kconfig - Add unit test --- MAINTAINERS | 7 +++++++ Makefile | 5 +++++ cmd/Kconfig | 10 ++++++++++ cmd/Makefile | 1 + cmd/stackprot_test.c | 21 +++++++++++++++++++++ common/Kconfig | 17 +++++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 19 +++++++++++++++++++ configs/sandbox_defconfig | 14 +++++++------- scripts/Makefile.spl | 6 ++++++ test/py/tests/test_stackprotector.py | 15 +++++++++++++++ 11 files changed, 110 insertions(+), 7 deletions(-) create mode 100644 cmd/stackprot_test.c create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/MAINTAINERS b/MAINTAINERS index 26dd254..d3971e8 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1024,6 +1024,13 @@ F: include/sqfs.h F: cmd/sqfs.c F: test/py/tests/test_fs/test_squashfs/
+STACKPROTECTOR +M: Joel Peshkin joel.peshkin@broadcom.com +S: Maintained +F: common/stackprot.c +F: cmd/stackprot_test.c +F: test/py/tests/test_stackprotector.py + TARGET_BCMNS3 M: Bharat Gooty bharat.gooty@broadcom.com M: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com diff --git a/Makefile b/Makefile index 902a976..65c5cb8 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,12 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +CFLAGS_EFI += $(call cc-option,-fno-stack-protector) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/cmd/Kconfig b/cmd/Kconfig index da86a94..054b2f3 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -2280,6 +2280,16 @@ config CMD_AVB avb read_part_hex - read data from partition and output to stdout avb write_part - write data to partition avb verify - run full verification chain + +config CMD_STACKPROTECTOR_TEST + bool "Test command for stack protector" + depends on STACKPROTECTOR + default n + help + Enable stackprot_test command + The stackprot_test command will force a stack overrun to test + the stack smashing detection mechanisms. + endmenu
config CMD_UBI diff --git a/cmd/Makefile b/cmd/Makefile index 5b3400a..1d7afea 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o obj-$(CONFIG_CMD_STRINGS) += strings.o obj-$(CONFIG_CMD_SMC) += smccc.o obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o obj-$(CONFIG_CMD_TERMINAL) += terminal.o obj-$(CONFIG_CMD_TIME) += time.o obj-$(CONFIG_CMD_TIMER) += timer.o diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c new file mode 100644 index 0000000..6ad287e --- /dev/null +++ b/cmd/stackprot_test.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> +#include <command.h> + +DECLARE_GLOBAL_DATA_PTR; + +static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + char a[128]; + + memset(a, 0xa5, 512); + return 0; +} + +U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail, + "test stack protector fail", ""); diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9..6a94045 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,23 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR + bool "Stack Protector buffer overflow detection" + default n + help + Enable stack smash detection through compiler's stack-protector + canary logic + +config SPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for SPL" + depends on STACKPROTECTOR && SPL + default n + +config TPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for TPL" + depends on STACKPROTECTOR && TPL + default n + endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d..fe71e18 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o + diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000..282c564 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> + +DECLARE_GLOBAL_DATA_PTR; + +unsigned long __stack_chk_guard = (unsigned long)(0xfeedf00ddeadbeef & ~0UL); + +void __stack_chk_fail(void) +{ + void *ra; + + ra = __builtin_extract_return_addr(__builtin_return_address(0)); + panic("Stack smashing detected in function:\n%p relocated from %p", + ra, ra - gd->reloc_off); +} diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index 58d4ef1..0c82ef2 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -20,11 +20,11 @@ CONFIG_BOOTSTAGE_STASH=y CONFIG_BOOTSTAGE_STASH_SIZE=0x4096 CONFIG_CONSOLE_RECORD=y CONFIG_CONSOLE_RECORD_OUT_SIZE=0x1000 -CONFIG_SILENT_CONSOLE=y CONFIG_PRE_CONSOLE_BUFFER=y CONFIG_LOG_SYSLOG=y CONFIG_LOG_ERROR_RETURN=y CONFIG_DISPLAY_BOARDINFO_LATE=y +CONFIG_STACKPROTECTOR=y CONFIG_ANDROID_AB=y CONFIG_CMD_CPU=y CONFIG_CMD_LICENSE=y @@ -96,6 +96,7 @@ CONFIG_CMD_CRAMFS=y CONFIG_CMD_EXT4_WRITE=y CONFIG_CMD_SQUASHFS=y CONFIG_CMD_MTDPARTS=y +CONFIG_CMD_STACKPROTECTOR_TEST=y CONFIG_MAC_PARTITION=y CONFIG_AMIGA_PARTITION=y CONFIG_OF_CONTROL=y @@ -131,6 +132,7 @@ CONFIG_CPU=y CONFIG_DM_DEMO=y CONFIG_DM_DEMO_SIMPLE=y CONFIG_DM_DEMO_SHAPE=y +CONFIG_DFU_SF=y CONFIG_DMA=y CONFIG_DMA_CHANNELS=y CONFIG_SANDBOX_DMA=y @@ -269,14 +271,12 @@ CONFIG_CMD_DHRYSTONE=y CONFIG_TPM=y CONFIG_LZ4=y CONFIG_ERRNO_STR=y +CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y +CONFIG_EFI_CAPSULE_ON_DISK=y +CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y +CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y CONFIG_EFI_SECURE_BOOT=y CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y -# -CONFIG_DFU_SF=y -CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y -CONFIG_EFI_CAPSULE_ON_DISK=y -CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y -CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 87021e2..6725201 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -67,6 +67,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif + # FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000..957a2a6 --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom + +import pytest +import signal + +@pytest.mark.buildconfigspec('cmd_stackprotector_test') +def test_stackprotector(u_boot_console): + """Test that the stackprotector function works.""" + + u_boot_console.run_command('stackprot_test',wait_for_prompt=False) + expected_response = 'Stack smashing detected' + u_boot_console.wait_for(expected_response) + assert(True) +
On 14.01.21 21:35, Joel Peshkin wrote:
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
Cc: Simon Glass sjg@chromium.org Cc: Heinrich Schuchardt xypron.glpk@gmx.de
Reviewed-by: Heinrich Schuchardt xypron.glpk@gmx.de
Changes for v8:
- Fix commit message
- Force canary to UL type
Changes for v7:
- Fix commit message
- add __builtin_extract_return_addr() calls
Changes for v6:
- Fix commit message
Changes for v5:
- Rebase
Changes for v4:
- Exclude EFI from stackprotector
- Cleanups of extra includes and declaration
Changes for v3:
- Move test command to cmd/
- Update Kconfig names and depends
- clean up default canary initialization
Changes for v2:
- Add test command and corresponding config
- Fixed incorrect description in Kconfig
- Add unit test
On Thu, Jan 14, 2021 at 12:35:35PM -0800, Joel Peshkin wrote:
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com Reviewed-by: Heinrich Schuchardt xypron.glpk@gmx.de
Oddly enough this cases a number of the TPM2 tests to fail on sandbox: https://dev.azure.com/u-boot/u-boot/_build/results?buildId=1706&view=log...
On 1/28/21 1:57 AM, Tom Rini wrote:
On Thu, Jan 14, 2021 at 12:35:35PM -0800, Joel Peshkin wrote:
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com Reviewed-by: Heinrich Schuchardt xypron.glpk@gmx.de
Oddly enough this cases a number of the TPM2 tests to fail on sandbox: https://dev.azure.com/u-boot/u-boot/_build/results?buildId=1706&view=log...
Thanks Tom for the head-up.
The problem is reproducible locally using 'make tests' with the patch applied on top of origin/master.
Best regards
Heinrich
On 28.01.21 09:20, Heinrich Schuchardt wrote:
On 1/28/21 1:57 AM, Tom Rini wrote:
On Thu, Jan 14, 2021 at 12:35:35PM -0800, Joel Peshkin wrote:
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com Reviewed-by: Heinrich Schuchardt xypron.glpk@gmx.de
Oddly enough this cases a number of the TPM2 tests to fail on sandbox: https://dev.azure.com/u-boot/u-boot/_build/results?buildId=1706&view=log...
Thanks Tom for the head-up.
The problem is reproducible locally using 'make tests' with the patch applied on top of origin/master.
Best regards
Heinrich
The stack protector has successfully detected stack smashes. See below.
A secondary finding is: panic("foo") without \n is not correctly flushed to the console on the sandbox.
test_tpm2_init:
Stack smashing detected in function: 00005563faa7c521 relocated from 000000000004d521
u-boot.map 0x000000000004cf44 do_spi 0x000000000004d9e9 print_byte_string
It seems that the output written in the stack-protector test ends up in the following test which happens to be test_tpm2_init:
static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) { 4d4db: 48 81 ec 98 00 00 00 sub $0x98,%rsp char a[128];
memset(a, 0xa5, 512); 4d4e2: ba 00 02 00 00 mov $0x200,%edx 4d4e7: be a5 00 00 00 mov $0xa5,%esi { 4d4ec: 64 48 8b 04 25 28 00 mov %fs:0x28,%rax 4d4f3: 00 00· 4d4f5: 48 89 84 24 88 00 00 mov %rax,0x88(%rsp) 4d4fc: 00· 4d4fd: 31 c0 xor %eax,%eax memset(a, 0xa5, 512); 4d4ff: 48 8d 7c 24 08 lea 0x8(%rsp),%rdi 4d504: e8 1f 34 0d 00 callq 120928 <memset> return 0; } 4d509: 48 8b 84 24 88 00 00 mov 0x88(%rsp),%rax 4d510: 00· 4d511: 64 48 2b 04 25 28 00 sub %fs:0x28,%rax 4d518: 00 00· 4d51a: 74 05 je 4d521 <do_test_stackprot_fail+0x46> 4d51c: e8 68 48 02 00 callq 71d89 <__stack_chk_fail>
4d521: 31 c0 xor %eax,%eax
4d523: 48 81 c4 98 00 00 00 add $0x98,%rsp 4d52a: c3 retq···
TestEfiCapsuleFirmwareFit.test_efi_capsule_fw3 #Stack smashing detected in function: 000055827c21cb58 relocated from 00000000000d8b58
Here we seem to have a real finding.
u-boot.map 0x00000000000d7fae efi_launch_capsules 0x00000000000da1ec set_shift_mask
efi_set_variable_int(L"CapsuleLast", &efi_guid_capsule_report, d8b10: 4c 8b 04 24 mov (%rsp),%r8 d8b14: 45 31 c9 xor %r9d,%r9d d8b17: 48 8d 35 42 1c 11 00 lea 0x111c42(%rip),%rsi # 1ea760 <efi_guid_capsule_report> d8b1e: b9 16 00 00 00 mov $0x16,%ecx d8b23: ba 07 00 00 80 mov $0x80000007,%edx d8b28: 48 8d 3d e7 61 0c 00 lea 0xc61e7(%rip),%rdi # 19ed16 <__func__.0+0x132e6> d8b2f: e8 34 ab 00 00 callq e3668 <efi_set_variable_int> return ret; d8b34: eb 0a jmp d8b40 <efi_launch_capsules+0xb92> return EFI_DEVICE_ERROR; d8b36: 49 bc 07 00 00 00 00 movabs $0x8000000000000007,%r12 d8b3d: 00 00 80· } d8b40: 48 8b 84 24 c8 00 00 mov 0xc8(%rsp),%rax d8b47: 00· d8b48: 64 48 2b 04 25 28 00 sub %fs:0x28,%rax d8b4f: 00 00· d8b51: 74 05 je d8b58 <efi_launch_capsules+0xbaa> d8b53: e8 31 92 f9 ff callq 71d89 <__stack_chk_fail>
d8b58: 48 81 c4 d8 00 00 00 add $0xd8,%rsp
d8b5f: 4c 89 e0 mov %r12,%rax d8b62: 5b pop %rbx d8b63: 5d pop %rbp d8b64: 41 5c pop %r12 d8b66: 41 5d pop %r13 d8b68: 41 5e pop %r14 d8b6a: 41 5f pop %r15 d8b6c: c3 retq···
Best regards
Heinrich
On 28.01.21 12:00, Heinrich Schuchardt wrote:
On 28.01.21 09:20, Heinrich Schuchardt wrote:
On 1/28/21 1:57 AM, Tom Rini wrote:
On Thu, Jan 14, 2021 at 12:35:35PM -0800, Joel Peshkin wrote:
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com Reviewed-by: Heinrich Schuchardt xypron.glpk@gmx.de
Oddly enough this cases a number of the TPM2 tests to fail on sandbox: https://dev.azure.com/u-boot/u-boot/_build/results?buildId=1706&view=log...
Thanks Tom for the head-up.
The problem is reproducible locally using 'make tests' with the patch applied on top of origin/master.
Best regards
Heinrich
The stack protector has successfully detected stack smashes. See below.
A secondary finding is: panic("foo") without \n is not correctly flushed to the console on the sandbox.
./test/py/test.py --bd=sandbox -ra --build-dir=build-sandbox -k='not test_stackprotector' shows no error for tpm2.
./test/py/test.py --bd=sandbox -ra --build-dir=build-sandbox -k='not test_stackprotector' shows the error for tpm2.
I think the test test_stackprotector() is broken. I causes the sandbox to reset but does not wait until reaches the prompt again, e.g add
u_boot_console.restart_uboot()
instead of assert(true).
@Joel Could you, please, submit a corrected patch.
@Takahiro For test/py/tests/test_efi_capsule/test_capsule_firmware.py I always see a smash. Could you, please, have a look at efi_launch_capsules().
Best regards
Heinrich
test_tpm2_init:
Stack smashing detected in function: 00005563faa7c521 relocated from 000000000004d521
u-boot.map 0x000000000004cf44 do_spi 0x000000000004d9e9 print_byte_string
It seems that the output written in the stack-protector test ends up in the following test which happens to be test_tpm2_init:
static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) { 4d4db: 48 81 ec 98 00 00 00 sub $0x98,%rsp char a[128];
memset(a, 0xa5, 512); 4d4e2: ba 00 02 00 00 mov $0x200,%edx 4d4e7: be a5 00 00 00 mov $0xa5,%esi { 4d4ec: 64 48 8b 04 25 28 00 mov %fs:0x28,%rax 4d4f3: 00 00· 4d4f5: 48 89 84 24 88 00 00 mov %rax,0x88(%rsp) 4d4fc: 00· 4d4fd: 31 c0 xor %eax,%eax memset(a, 0xa5, 512); 4d4ff: 48 8d 7c 24 08 lea 0x8(%rsp),%rdi 4d504: e8 1f 34 0d 00 callq 120928 <memset> return 0; } 4d509: 48 8b 84 24 88 00 00 mov 0x88(%rsp),%rax 4d510: 00· 4d511: 64 48 2b 04 25 28 00 sub %fs:0x28,%rax 4d518: 00 00· 4d51a: 74 05 je 4d521 <do_test_stackprot_fail+0x46> 4d51c: e8 68 48 02 00 callq 71d89 <__stack_chk_fail>
4d521: 31 c0 xor %eax,%eax
4d523: 48 81 c4 98 00 00 00 add $0x98,%rsp 4d52a: c3 retq···
TestEfiCapsuleFirmwareFit.test_efi_capsule_fw3 #Stack smashing detected in function: 000055827c21cb58 relocated from 00000000000d8b58
Here we seem to have a real finding.
u-boot.map 0x00000000000d7fae efi_launch_capsules 0x00000000000da1ec set_shift_mask
efi_set_variable_int(L"CapsuleLast", &efi_guid_capsule_report, d8b10: 4c 8b 04 24 mov (%rsp),%r8 d8b14: 45 31 c9 xor %r9d,%r9d d8b17: 48 8d 35 42 1c 11 00 lea 0x111c42(%rip),%rsi # 1ea760 <efi_guid_capsule_report> d8b1e: b9 16 00 00 00 mov $0x16,%ecx d8b23: ba 07 00 00 80 mov $0x80000007,%edx d8b28: 48 8d 3d e7 61 0c 00 lea 0xc61e7(%rip),%rdi # 19ed16 <__func__.0+0x132e6> d8b2f: e8 34 ab 00 00 callq e3668 <efi_set_variable_int> return ret; d8b34: eb 0a jmp d8b40 <efi_launch_capsules+0xb92> return EFI_DEVICE_ERROR; d8b36: 49 bc 07 00 00 00 00 movabs $0x8000000000000007,%r12 d8b3d: 00 00 80· } d8b40: 48 8b 84 24 c8 00 00 mov 0xc8(%rsp),%rax d8b47: 00· d8b48: 64 48 2b 04 25 28 00 sub %fs:0x28,%rax d8b4f: 00 00· d8b51: 74 05 je d8b58 <efi_launch_capsules+0xbaa> d8b53: e8 31 92 f9 ff callq 71d89 <__stack_chk_fail>
d8b58: 48 81 c4 d8 00 00 00 add $0xd8,%rsp
d8b5f: 4c 89 e0 mov %r12,%rax d8b62: 5b pop %rbx d8b63: 5d pop %rbp d8b64: 41 5c pop %r12 d8b66: 41 5d pop %r13 d8b68: 41 5e pop %r14 d8b6a: 41 5f pop %r15 d8b6c: c3 retq···
Best regards
Heinrich
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com --- Cc: Simon Glass sjg@chromium.org Cc: Heinrich Schuchardt xypron.glpk@gmx.de
Changes for v9: - Fix pytest script post-test reboot Changes for v8: - Fix commit message - Force canary to UL type Changes for v7: - Fix commit message - add __builtin_extract_return_addr() calls Changes for v6: - Fix commit message Changes for v5: - Rebase Changes for v4: - Exclude EFI from stackprotector - Cleanups of extra includes and declaration Changes for v3: - Move test command to cmd/ - Update Kconfig names and depends - clean up default canary initialization Changes for v2: - Add test command and corresponding config - Fixed incorrect description in Kconfig - Add unit test --- MAINTAINERS | 7 +++++++ Makefile | 5 +++++ cmd/Kconfig | 10 ++++++++++ cmd/Makefile | 1 + cmd/stackprot_test.c | 21 +++++++++++++++++++++ common/Kconfig | 17 +++++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 19 +++++++++++++++++++ configs/sandbox_defconfig | 14 +++++++------- scripts/Makefile.spl | 6 ++++++ test/py/tests/test_stackprotector.py | 15 +++++++++++++++ 11 files changed, 110 insertions(+), 7 deletions(-) create mode 100644 cmd/stackprot_test.c create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/MAINTAINERS b/MAINTAINERS index 26dd254..d3971e8 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1024,6 +1024,13 @@ F: include/sqfs.h F: cmd/sqfs.c F: test/py/tests/test_fs/test_squashfs/
+STACKPROTECTOR +M: Joel Peshkin joel.peshkin@broadcom.com +S: Maintained +F: common/stackprot.c +F: cmd/stackprot_test.c +F: test/py/tests/test_stackprotector.py + TARGET_BCMNS3 M: Bharat Gooty bharat.gooty@broadcom.com M: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com diff --git a/Makefile b/Makefile index 902a976..65c5cb8 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,12 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +CFLAGS_EFI += $(call cc-option,-fno-stack-protector) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/cmd/Kconfig b/cmd/Kconfig index da86a94..054b2f3 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -2280,6 +2280,16 @@ config CMD_AVB avb read_part_hex - read data from partition and output to stdout avb write_part - write data to partition avb verify - run full verification chain + +config CMD_STACKPROTECTOR_TEST + bool "Test command for stack protector" + depends on STACKPROTECTOR + default n + help + Enable stackprot_test command + The stackprot_test command will force a stack overrun to test + the stack smashing detection mechanisms. + endmenu
config CMD_UBI diff --git a/cmd/Makefile b/cmd/Makefile index 5b3400a..1d7afea 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o obj-$(CONFIG_CMD_STRINGS) += strings.o obj-$(CONFIG_CMD_SMC) += smccc.o obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o obj-$(CONFIG_CMD_TERMINAL) += terminal.o obj-$(CONFIG_CMD_TIME) += time.o obj-$(CONFIG_CMD_TIMER) += timer.o diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c new file mode 100644 index 0000000..6ad287e --- /dev/null +++ b/cmd/stackprot_test.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> +#include <command.h> + +DECLARE_GLOBAL_DATA_PTR; + +static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + char a[128]; + + memset(a, 0xa5, 512); + return 0; +} + +U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail, + "test stack protector fail", ""); diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9..6a94045 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,23 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR + bool "Stack Protector buffer overflow detection" + default n + help + Enable stack smash detection through compiler's stack-protector + canary logic + +config SPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for SPL" + depends on STACKPROTECTOR && SPL + default n + +config TPL_STACKPROTECTOR + bool "Stack Protector buffer overflow detection for TPL" + depends on STACKPROTECTOR && TPL + default n + endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d..fe71e18 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o + diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000..282c564 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2021 Broadcom + */ + +#include <common.h> + +DECLARE_GLOBAL_DATA_PTR; + +unsigned long __stack_chk_guard = (unsigned long)(0xfeedf00ddeadbeef & ~0UL); + +void __stack_chk_fail(void) +{ + void *ra; + + ra = __builtin_extract_return_addr(__builtin_return_address(0)); + panic("Stack smashing detected in function:\n%p relocated from %p", + ra, ra - gd->reloc_off); +} diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index 58d4ef1..0c82ef2 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -20,11 +20,11 @@ CONFIG_BOOTSTAGE_STASH=y CONFIG_BOOTSTAGE_STASH_SIZE=0x4096 CONFIG_CONSOLE_RECORD=y CONFIG_CONSOLE_RECORD_OUT_SIZE=0x1000 -CONFIG_SILENT_CONSOLE=y CONFIG_PRE_CONSOLE_BUFFER=y CONFIG_LOG_SYSLOG=y CONFIG_LOG_ERROR_RETURN=y CONFIG_DISPLAY_BOARDINFO_LATE=y +CONFIG_STACKPROTECTOR=y CONFIG_ANDROID_AB=y CONFIG_CMD_CPU=y CONFIG_CMD_LICENSE=y @@ -96,6 +96,7 @@ CONFIG_CMD_CRAMFS=y CONFIG_CMD_EXT4_WRITE=y CONFIG_CMD_SQUASHFS=y CONFIG_CMD_MTDPARTS=y +CONFIG_CMD_STACKPROTECTOR_TEST=y CONFIG_MAC_PARTITION=y CONFIG_AMIGA_PARTITION=y CONFIG_OF_CONTROL=y @@ -131,6 +132,7 @@ CONFIG_CPU=y CONFIG_DM_DEMO=y CONFIG_DM_DEMO_SIMPLE=y CONFIG_DM_DEMO_SHAPE=y +CONFIG_DFU_SF=y CONFIG_DMA=y CONFIG_DMA_CHANNELS=y CONFIG_SANDBOX_DMA=y @@ -269,14 +271,12 @@ CONFIG_CMD_DHRYSTONE=y CONFIG_TPM=y CONFIG_LZ4=y CONFIG_ERRNO_STR=y +CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y +CONFIG_EFI_CAPSULE_ON_DISK=y +CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y +CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y CONFIG_EFI_SECURE_BOOT=y CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y -# -CONFIG_DFU_SF=y -CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y -CONFIG_EFI_CAPSULE_ON_DISK=y -CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y -CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 87021e2..6725201 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -67,6 +67,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif + # FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000..7aeec5e --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom + +import pytest +import signal + +@pytest.mark.buildconfigspec('cmd_stackprotector_test') +def test_stackprotector(u_boot_console): + """Test that the stackprotector function works.""" + + u_boot_console.run_command('stackprot_test',wait_for_prompt=False) + expected_response = 'Stack smashing detected' + u_boot_console.wait_for(expected_response) + u_boot_console.restart_uboot() +
On 09.02.21 04:36, Joel Peshkin wrote:
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
Cc: Simon Glass sjg@chromium.org Cc: Heinrich Schuchardt xypron.glpk@gmx.de
Changes for v9:
- Fix pytest script post-test reboot
Changes for v8:
- Fix commit message
- Force canary to UL type
Changes for v7:
- Fix commit message
- add __builtin_extract_return_addr() calls
Changes for v6:
- Fix commit message
Changes for v5:
- Rebase
Changes for v4:
- Exclude EFI from stackprotector
- Cleanups of extra includes and declaration
Changes for v3:
- Move test command to cmd/
- Update Kconfig names and depends
- clean up default canary initialization
Changes for v2:
- Add test command and corresponding config
- Fixed incorrect description in Kconfig
- Add unit test
MAINTAINERS | 7 +++++++ Makefile | 5 +++++ cmd/Kconfig | 10 ++++++++++ cmd/Makefile | 1 + cmd/stackprot_test.c | 21 +++++++++++++++++++++ common/Kconfig | 17 +++++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 19 +++++++++++++++++++ configs/sandbox_defconfig | 14 +++++++------- scripts/Makefile.spl | 6 ++++++ test/py/tests/test_stackprotector.py | 15 +++++++++++++++ 11 files changed, 110 insertions(+), 7 deletions(-) create mode 100644 cmd/stackprot_test.c create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/MAINTAINERS b/MAINTAINERS index 26dd254..d3971e8 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1024,6 +1024,13 @@ F: include/sqfs.h F: cmd/sqfs.c F: test/py/tests/test_fs/test_squashfs/
+STACKPROTECTOR +M: Joel Peshkin joel.peshkin@broadcom.com +S: Maintained +F: common/stackprot.c +F: cmd/stackprot_test.c +F: test/py/tests/test_stackprotector.py
TARGET_BCMNS3 M: Bharat Gooty bharat.gooty@broadcom.com M: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com diff --git a/Makefile b/Makefile index 902a976..65c5cb8 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,12 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +CFLAGS_EFI += $(call cc-option,-fno-stack-protector) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/cmd/Kconfig b/cmd/Kconfig index da86a94..054b2f3 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -2280,6 +2280,16 @@ config CMD_AVB avb read_part_hex - read data from partition and output to stdout avb write_part - write data to partition avb verify - run full verification chain
+config CMD_STACKPROTECTOR_TEST
- bool "Test command for stack protector"
- depends on STACKPROTECTOR
- default n
- help
Enable stackprot_test commandThe stackprot_test command will force a stack overrun to testthe stack smashing detection mechanisms.endmenu
config CMD_UBI diff --git a/cmd/Makefile b/cmd/Makefile index 5b3400a..1d7afea 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o obj-$(CONFIG_CMD_STRINGS) += strings.o obj-$(CONFIG_CMD_SMC) += smccc.o obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o obj-$(CONFIG_CMD_TERMINAL) += terminal.o obj-$(CONFIG_CMD_TIME) += time.o obj-$(CONFIG_CMD_TIMER) += timer.o diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c new file mode 100644 index 0000000..6ad287e --- /dev/null +++ b/cmd/stackprot_test.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021 Broadcom
- */
+#include <common.h> +#include <command.h>
+DECLARE_GLOBAL_DATA_PTR;
Hello Joël,
This line is not needed.
+static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])+{
- char a[128];
- memset(a, 0xa5, 512);
- return 0;
+}
+U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail,
"test stack protector fail", "");diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9..6a94045 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,23 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR
- bool "Stack Protector buffer overflow detection"
- default n
- help
Enable stack smash detection through compiler's stack-protectorcanary logic+config SPL_STACKPROTECTOR
- bool "Stack Protector buffer overflow detection for SPL"
- depends on STACKPROTECTOR && SPL
- default n
+config TPL_STACKPROTECTOR
- bool "Stack Protector buffer overflow detection for TPL"
- depends on STACKPROTECTOR && TPL
- default n
endmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d..fe71e18 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o
diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000..282c564 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021 Broadcom
- */
+#include <common.h>
You need
#include <asm/global_data.h>
here due to recently merged restructuring of includes by Simon.
+DECLARE_GLOBAL_DATA_PTR;
common/stackprot.c:8:1: warning: data definition has no type or storage class 8 | DECLARE_GLOBAL_DATA_PTR; | ^~~~~~~~~~~~~~~~~~~~~~~ common/stackprot.c:8:1: warning: type defaults to ‘int’ in declaration of ‘DECLARE_GLOBAL_DATA_PTR’ [-Wimplicit-int] common/stackprot.c: In function ‘__stack_chk_fail’: common/stackprot.c:18:17: error: ‘gd’ undeclared (first use in this function) 18 | ra, ra - gd->reloc_off);
+unsigned long __stack_chk_guard = (unsigned long)(0xfeedf00ddeadbeef & ~0UL);
+void __stack_chk_fail(void) +{
- void *ra;
- ra = __builtin_extract_return_addr(__builtin_return_address(0));
- panic("Stack smashing detected in function:\n%p relocated from %p",
ra, ra - gd->reloc_off);+} diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index 58d4ef1..0c82ef2 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -20,11 +20,11 @@ CONFIG_BOOTSTAGE_STASH=y CONFIG_BOOTSTAGE_STASH_SIZE=0x4096 CONFIG_CONSOLE_RECORD=y CONFIG_CONSOLE_RECORD_OUT_SIZE=0x1000 -CONFIG_SILENT_CONSOLE=y CONFIG_PRE_CONSOLE_BUFFER=y CONFIG_LOG_SYSLOG=y CONFIG_LOG_ERROR_RETURN=y CONFIG_DISPLAY_BOARDINFO_LATE=y +CONFIG_STACKPROTECTOR=y CONFIG_ANDROID_AB=y CONFIG_CMD_CPU=y CONFIG_CMD_LICENSE=y @@ -96,6 +96,7 @@ CONFIG_CMD_CRAMFS=y CONFIG_CMD_EXT4_WRITE=y CONFIG_CMD_SQUASHFS=y CONFIG_CMD_MTDPARTS=y +CONFIG_CMD_STACKPROTECTOR_TEST=y CONFIG_MAC_PARTITION=y CONFIG_AMIGA_PARTITION=y CONFIG_OF_CONTROL=y @@ -131,6 +132,7 @@ CONFIG_CPU=y CONFIG_DM_DEMO=y CONFIG_DM_DEMO_SIMPLE=y CONFIG_DM_DEMO_SHAPE=y +CONFIG_DFU_SF=y CONFIG_DMA=y CONFIG_DMA_CHANNELS=y CONFIG_SANDBOX_DMA=y @@ -269,14 +271,12 @@ CONFIG_CMD_DHRYSTONE=y CONFIG_TPM=y CONFIG_LZ4=y CONFIG_ERRNO_STR=y +CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y +CONFIG_EFI_CAPSULE_ON_DISK=y +CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y +CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y CONFIG_EFI_SECURE_BOOT=y CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y -# -CONFIG_DFU_SF=y -CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y -CONFIG_EFI_CAPSULE_ON_DISK=y -CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y -CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 87021e2..6725201 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -67,6 +67,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif
# FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py new file mode 100644 index 0000000..7aeec5e --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom
+import pytest +import signal
+@pytest.mark.buildconfigspec('cmd_stackprotector_test') +def test_stackprotector(u_boot_console):
- """Test that the stackprotector function works."""
- u_boot_console.run_command('stackprot_test',wait_for_prompt=False)
- expected_response = 'Stack smashing detected'
- u_boot_console.wait_for(expected_response)
- u_boot_console.restart_uboot()
Hi Heinrich,
Has there been any progress in getting the EFI erors fixed so that this can be committed? There seems to be little point in my refreshing this patch until that is done.
Thanks,
-Joel
On Mon, Mar 22, 2021 at 10:37 AM Heinrich Schuchardt xypron.glpk@gmx.de wrote:
On 09.02.21 04:36, Joel Peshkin wrote:
Add support for stack protector for UBOOT, SPL, and TPL as well as new pytest for stackprotector
Signed-off-by: Joel Peshkin joel.peshkin@broadcom.com
Cc: Simon Glass sjg@chromium.org Cc: Heinrich Schuchardt xypron.glpk@gmx.de
Changes for v9:
- Fix pytest script post-test reboot
Changes for v8:
- Fix commit message
- Force canary to UL type
Changes for v7:
- Fix commit message
- add __builtin_extract_return_addr() calls
Changes for v6:
- Fix commit message
Changes for v5:
- Rebase
Changes for v4:
- Exclude EFI from stackprotector
- Cleanups of extra includes and declaration
Changes for v3:
- Move test command to cmd/
- Update Kconfig names and depends
- clean up default canary initialization
Changes for v2:
- Add test command and corresponding config
- Fixed incorrect description in Kconfig
- Add unit test
MAINTAINERS | 7 +++++++ Makefile | 5 +++++ cmd/Kconfig | 10 ++++++++++ cmd/Makefile | 1 + cmd/stackprot_test.c | 21 +++++++++++++++++++++ common/Kconfig | 17 +++++++++++++++++ common/Makefile | 2 ++ common/stackprot.c | 19 +++++++++++++++++++ configs/sandbox_defconfig | 14 +++++++------- scripts/Makefile.spl | 6 ++++++ test/py/tests/test_stackprotector.py | 15 +++++++++++++++ 11 files changed, 110 insertions(+), 7 deletions(-) create mode 100644 cmd/stackprot_test.c create mode 100644 common/stackprot.c create mode 100644 test/py/tests/test_stackprotector.py
diff --git a/MAINTAINERS b/MAINTAINERS index 26dd254..d3971e8 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1024,6 +1024,13 @@ F: include/sqfs.h F: cmd/sqfs.c F: test/py/tests/test_fs/test_squashfs/
+STACKPROTECTOR +M: Joel Peshkin joel.peshkin@broadcom.com +S: Maintained +F: common/stackprot.c +F: cmd/stackprot_test.c +F: test/py/tests/test_stackprotector.py
TARGET_BCMNS3 M: Bharat Gooty bharat.gooty@broadcom.com M: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com diff --git a/Makefile b/Makefile index 902a976..65c5cb8 100644 --- a/Makefile +++ b/Makefile @@ -677,7 +677,12 @@ else KBUILD_CFLAGS += -O2 endif
+ifeq ($(CONFIG_STACKPROTECTOR),y) +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) +CFLAGS_EFI += $(call cc-option,-fno-stack-protector) +else KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) +endif KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable stringop warnings in gcc 8+ diff --git a/cmd/Kconfig b/cmd/Kconfig index da86a94..054b2f3 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -2280,6 +2280,16 @@ config CMD_AVB avb read_part_hex - read data from partition and output to
stdout
avb write_part - write data to partition avb verify - run full verification chain
+config CMD_STACKPROTECTOR_TEST
bool "Test command for stack protector"depends on STACKPROTECTORdefault nhelpEnable stackprot_test commandThe stackprot_test command will force a stack overrun to testthe stack smashing detection mechanisms.endmenu
config CMD_UBI diff --git a/cmd/Makefile b/cmd/Makefile index 5b3400a..1d7afea 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o obj-$(CONFIG_CMD_STRINGS) += strings.o obj-$(CONFIG_CMD_SMC) += smccc.o obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o obj-$(CONFIG_CMD_TERMINAL) += terminal.o obj-$(CONFIG_CMD_TIME) += time.o obj-$(CONFIG_CMD_TIMER) += timer.o diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c new file mode 100644 index 0000000..6ad287e --- /dev/null +++ b/cmd/stackprot_test.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021 Broadcom
- */
+#include <common.h> +#include <command.h>
+DECLARE_GLOBAL_DATA_PTR;
Hello Joël,
This line is not needed.
+static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int
argc,
char *const argv[])+{
char a[128];memset(a, 0xa5, 512);return 0;+}
+U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail,
"test stack protector fail", "");diff --git a/common/Kconfig b/common/Kconfig index 2bce8c9..6a94045 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -595,6 +595,23 @@ config TPL_HASH and the algorithms it supports are defined in common/hash.c. See also CMD_HASH for command-line access.
+config STACKPROTECTOR
bool "Stack Protector buffer overflow detection"default nhelpEnable stack smash detection through compiler's stack-protectorcanary logic+config SPL_STACKPROTECTOR
bool "Stack Protector buffer overflow detection for SPL"depends on STACKPROTECTOR && SPLdefault n+config TPL_STACKPROTECTOR
bool "Stack Protector buffer overflow detection for TPL"depends on STACKPROTECTOR && TPLdefault nendmenu
menu "Update support" diff --git a/common/Makefile b/common/Makefile index bcf352d..fe71e18 100644 --- a/common/Makefile +++ b/common/Makefile @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o
obj-$(CONFIG_AVB_VERIFY) += avb_verify.o +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o
diff --git a/common/stackprot.c b/common/stackprot.c new file mode 100644 index 0000000..282c564 --- /dev/null +++ b/common/stackprot.c @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2021 Broadcom
- */
+#include <common.h>
You need
#include <asm/global_data.h>here due to recently merged restructuring of includes by Simon.
+DECLARE_GLOBAL_DATA_PTR;
common/stackprot.c:8:1: warning: data definition has no type or storage class 8 | DECLARE_GLOBAL_DATA_PTR; | ^~~~~~~~~~~~~~~~~~~~~~~ common/stackprot.c:8:1: warning: type defaults to ‘int’ in declaration of ‘DECLARE_GLOBAL_DATA_PTR’ [-Wimplicit-int] common/stackprot.c: In function ‘__stack_chk_fail’: common/stackprot.c:18:17: error: ‘gd’ undeclared (first use in this function) 18 | ra, ra - gd->reloc_off);
+unsigned long __stack_chk_guard = (unsigned long)(0xfeedf00ddeadbeef &
~0UL);
+void __stack_chk_fail(void) +{
void *ra;ra = __builtin_extract_return_addr(__builtin_return_address(0));panic("Stack smashing detected in function:\n%p relocated from %p",ra, ra - gd->reloc_off);+} diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig index 58d4ef1..0c82ef2 100644 --- a/configs/sandbox_defconfig +++ b/configs/sandbox_defconfig @@ -20,11 +20,11 @@ CONFIG_BOOTSTAGE_STASH=y CONFIG_BOOTSTAGE_STASH_SIZE=0x4096 CONFIG_CONSOLE_RECORD=y CONFIG_CONSOLE_RECORD_OUT_SIZE=0x1000 -CONFIG_SILENT_CONSOLE=y CONFIG_PRE_CONSOLE_BUFFER=y CONFIG_LOG_SYSLOG=y CONFIG_LOG_ERROR_RETURN=y CONFIG_DISPLAY_BOARDINFO_LATE=y +CONFIG_STACKPROTECTOR=y CONFIG_ANDROID_AB=y CONFIG_CMD_CPU=y CONFIG_CMD_LICENSE=y @@ -96,6 +96,7 @@ CONFIG_CMD_CRAMFS=y CONFIG_CMD_EXT4_WRITE=y CONFIG_CMD_SQUASHFS=y CONFIG_CMD_MTDPARTS=y +CONFIG_CMD_STACKPROTECTOR_TEST=y CONFIG_MAC_PARTITION=y CONFIG_AMIGA_PARTITION=y CONFIG_OF_CONTROL=y @@ -131,6 +132,7 @@ CONFIG_CPU=y CONFIG_DM_DEMO=y CONFIG_DM_DEMO_SIMPLE=y CONFIG_DM_DEMO_SHAPE=y +CONFIG_DFU_SF=y CONFIG_DMA=y CONFIG_DMA_CHANNELS=y CONFIG_SANDBOX_DMA=y @@ -269,14 +271,12 @@ CONFIG_CMD_DHRYSTONE=y CONFIG_TPM=y CONFIG_LZ4=y CONFIG_ERRNO_STR=y +CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y +CONFIG_EFI_CAPSULE_ON_DISK=y +CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y +CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y CONFIG_EFI_SECURE_BOOT=y CONFIG_TEST_FDTDEC=y CONFIG_UNIT_TEST=y CONFIG_UT_TIME=y CONFIG_UT_DM=y -# -CONFIG_DFU_SF=y -CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y -CONFIG_EFI_CAPSULE_ON_DISK=y -CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y -CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl index 87021e2..6725201 100644 --- a/scripts/Makefile.spl +++ b/scripts/Makefile.spl @@ -67,6 +67,12 @@ include $(srctree)/scripts/Makefile.lib KBUILD_CFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections
+ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) +KBUILD_CFLAGS += -fstack-protector-strong +else +KBUILD_CFLAGS += -fno-stack-protector +endif
# FIX ME cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ $(NOSTDINC_FLAGS) diff --git a/test/py/tests/test_stackprotector.py
b/test/py/tests/test_stackprotector.py
new file mode 100644 index 0000000..7aeec5e --- /dev/null +++ b/test/py/tests/test_stackprotector.py @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Broadcom
+import pytest +import signal
+@pytest.mark.buildconfigspec('cmd_stackprotector_test') +def test_stackprotector(u_boot_console):
- """Test that the stackprotector function works."""
- u_boot_console.run_command('stackprot_test',wait_for_prompt=False)
- expected_response = 'Stack smashing detected'
- u_boot_console.wait_for(expected_response)
- u_boot_console.restart_uboot()
On 4/10/21 12:27 AM, Joel Peshkin wrote:
Hi Heinrich,
Has there been any progress in getting the EFI erors fixed so that this can be committed? There seems to be little point in my refreshing this patch until that is done.
I have fixed up your patch to work with EFI and will add it to my next pull request.
I did not get qemu-x86_64_defconfig and qemu-x86_defconfig to build with CONFIG_STACK_PROTECTOR=y, CONFIG_SPL_STACK_PROTECTOR = no.
arch/x86/cpu/irq.c and arch/x86/cpu/mtrr.c give me an undefined reference to `__stack_chk_fail' when SPL is built. It seems that these files are only built once instead of separately for SPL and main U-Boot.
Best regards
Heinrich
Thanks,
-Joel
On Mon, Mar 22, 2021 at 10:37 AM Heinrich Schuchardt <xypron.glpk@gmx.de mailto:xypron.glpk@gmx.de> wrote:
On 09.02.21 04:36, Joel Peshkin wrote: > Add support for stack protector for UBOOT, SPL, and TPL > as well as new pytest for stackprotector > > Signed-off-by: Joel Peshkin <joel.peshkin@broadcom.com <mailto:joel.peshkin@broadcom.com>> > --- > Cc: Simon Glass <sjg@chromium.org <mailto:sjg@chromium.org>> > Cc: Heinrich Schuchardt <xypron.glpk@gmx.de <mailto:xypron.glpk@gmx.de>> > > Changes for v9: > - Fix pytest script post-test reboot > Changes for v8: > - Fix commit message > - Force canary to UL type > Changes for v7: > - Fix commit message > - add __builtin_extract_return_addr() calls > Changes for v6: > - Fix commit message > Changes for v5: > - Rebase > Changes for v4: > - Exclude EFI from stackprotector > - Cleanups of extra includes and declaration > Changes for v3: > - Move test command to cmd/ > - Update Kconfig names and depends > - clean up default canary initialization > Changes for v2: > - Add test command and corresponding config > - Fixed incorrect description in Kconfig > - Add unit test > --- > MAINTAINERS | 7 +++++++ > Makefile | 5 +++++ > cmd/Kconfig | 10 ++++++++++ > cmd/Makefile | 1 + > cmd/stackprot_test.c | 21 +++++++++++++++++++++ > common/Kconfig | 17 +++++++++++++++++ > common/Makefile | 2 ++ > common/stackprot.c | 19 +++++++++++++++++++ > configs/sandbox_defconfig | 14 +++++++------- > scripts/Makefile.spl | 6 ++++++ > test/py/tests/test_stackprotector.py | 15 +++++++++++++++ > 11 files changed, 110 insertions(+), 7 deletions(-) > create mode 100644 cmd/stackprot_test.c > create mode 100644 common/stackprot.c > create mode 100644 test/py/tests/test_stackprotector.py > > diff --git a/MAINTAINERS b/MAINTAINERS > index 26dd254..d3971e8 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -1024,6 +1024,13 @@ F: include/sqfs.h > F: cmd/sqfs.c > F: test/py/tests/test_fs/test_squashfs/ > > +STACKPROTECTOR > +M: Joel Peshkin <joel.peshkin@broadcom.com <mailto:joel.peshkin@broadcom.com>> > +S: Maintained > +F: common/stackprot.c > +F: cmd/stackprot_test.c > +F: test/py/tests/test_stackprotector.py > + > TARGET_BCMNS3 > M: Bharat Gooty <bharat.gooty@broadcom.com <mailto:bharat.gooty@broadcom.com>> > M: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com <mailto:rayagonda.kokatanur@broadcom.com>> > diff --git a/Makefile b/Makefile > index 902a976..65c5cb8 100644 > --- a/Makefile > +++ b/Makefile > @@ -677,7 +677,12 @@ else > KBUILD_CFLAGS += -O2 > endif > > +ifeq ($(CONFIG_STACKPROTECTOR),y) > +KBUILD_CFLAGS += $(call cc-option,-fstack-protector-strong) > +CFLAGS_EFI += $(call cc-option,-fno-stack-protector) > +else > KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) > +endif > KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks) > > # disable stringop warnings in gcc 8+ > diff --git a/cmd/Kconfig b/cmd/Kconfig > index da86a94..054b2f3 100644 > --- a/cmd/Kconfig > +++ b/cmd/Kconfig > @@ -2280,6 +2280,16 @@ config CMD_AVB > avb read_part_hex - read data from partition and output to stdout > avb write_part - write data to partition > avb verify - run full verification chain > + > +config CMD_STACKPROTECTOR_TEST > + bool "Test command for stack protector" > + depends on STACKPROTECTOR > + default n > + help > + Enable stackprot_test command > + The stackprot_test command will force a stack overrun to test > + the stack smashing detection mechanisms. > + > endmenu > > config CMD_UBI > diff --git a/cmd/Makefile b/cmd/Makefile > index 5b3400a..1d7afea 100644 > --- a/cmd/Makefile > +++ b/cmd/Makefile > @@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_SPI) += spi.o > obj-$(CONFIG_CMD_STRINGS) += strings.o > obj-$(CONFIG_CMD_SMC) += smccc.o > obj-$(CONFIG_CMD_SYSBOOT) += sysboot.o pxe_utils.o > +obj-$(CONFIG_CMD_STACKPROTECTOR_TEST) += stackprot_test.o > obj-$(CONFIG_CMD_TERMINAL) += terminal.o > obj-$(CONFIG_CMD_TIME) += time.o > obj-$(CONFIG_CMD_TIMER) += timer.o > diff --git a/cmd/stackprot_test.c b/cmd/stackprot_test.c > new file mode 100644 > index 0000000..6ad287e > --- /dev/null > +++ b/cmd/stackprot_test.c > @@ -0,0 +1,21 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Copyright 2021 Broadcom > + */ > + > +#include <common.h> > +#include <command.h> > + > +DECLARE_GLOBAL_DATA_PTR; Hello Joël, This line is not needed. > + > +static int do_test_stackprot_fail(struct cmd_tbl *cmdtp, int flag, int argc, > + char *const argv[]) > +{ > + char a[128]; > + > + memset(a, 0xa5, 512); > + return 0; > +} > + > +U_BOOT_CMD(stackprot_test, 1, 1, do_test_stackprot_fail, > + "test stack protector fail", ""); > diff --git a/common/Kconfig b/common/Kconfig > index 2bce8c9..6a94045 100644 > --- a/common/Kconfig > +++ b/common/Kconfig > @@ -595,6 +595,23 @@ config TPL_HASH > and the algorithms it supports are defined in common/hash.c. See > also CMD_HASH for command-line access. > > +config STACKPROTECTOR > + bool "Stack Protector buffer overflow detection" > + default n > + help > + Enable stack smash detection through compiler's stack-protector > + canary logic > + > +config SPL_STACKPROTECTOR > + bool "Stack Protector buffer overflow detection for SPL" > + depends on STACKPROTECTOR && SPL > + default n > + > +config TPL_STACKPROTECTOR > + bool "Stack Protector buffer overflow detection for TPL" > + depends on STACKPROTECTOR && TPL > + default n > + > endmenu > > menu "Update support" > diff --git a/common/Makefile b/common/Makefile > index bcf352d..fe71e18 100644 > --- a/common/Makefile > +++ b/common/Makefile > @@ -138,3 +138,5 @@ obj-$(CONFIG_CMD_LOADB) += xyzModem.o > obj-$(CONFIG_$(SPL_TPL_)YMODEM_SUPPORT) += xyzModem.o > > obj-$(CONFIG_AVB_VERIFY) += avb_verify.o > +obj-$(CONFIG_$(SPL_TPL_)STACKPROTECTOR) += stackprot.o > + > diff --git a/common/stackprot.c b/common/stackprot.c > new file mode 100644 > index 0000000..282c564 > --- /dev/null > +++ b/common/stackprot.c > @@ -0,0 +1,19 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Copyright 2021 Broadcom > + */ > + > +#include <common.h> You need #include <asm/global_data.h> here due to recently merged restructuring of includes by Simon. > + > +DECLARE_GLOBAL_DATA_PTR; common/stackprot.c:8:1: warning: data definition has no type or storage class 8 | DECLARE_GLOBAL_DATA_PTR; | ^~~~~~~~~~~~~~~~~~~~~~~ common/stackprot.c:8:1: warning: type defaults to ‘int’ in declaration of ‘DECLARE_GLOBAL_DATA_PTR’ [-Wimplicit-int] common/stackprot.c: In function ‘__stack_chk_fail’: common/stackprot.c:18:17: error: ‘gd’ undeclared (first use in this function) 18 | ra, ra - gd->reloc_off); > + > +unsigned long __stack_chk_guard = (unsigned long)(0xfeedf00ddeadbeef & ~0UL); > + > +void __stack_chk_fail(void) > +{ > + void *ra; > + > + ra = __builtin_extract_return_addr(__builtin_return_address(0)); > + panic("Stack smashing detected in function:\n%p relocated from %p", > + ra, ra - gd->reloc_off); > +} > diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig > index 58d4ef1..0c82ef2 100644 > --- a/configs/sandbox_defconfig > +++ b/configs/sandbox_defconfig > @@ -20,11 +20,11 @@ CONFIG_BOOTSTAGE_STASH=y > CONFIG_BOOTSTAGE_STASH_SIZE=0x4096 > CONFIG_CONSOLE_RECORD=y > CONFIG_CONSOLE_RECORD_OUT_SIZE=0x1000 > -CONFIG_SILENT_CONSOLE=y > CONFIG_PRE_CONSOLE_BUFFER=y > CONFIG_LOG_SYSLOG=y > CONFIG_LOG_ERROR_RETURN=y > CONFIG_DISPLAY_BOARDINFO_LATE=y > +CONFIG_STACKPROTECTOR=y > CONFIG_ANDROID_AB=y > CONFIG_CMD_CPU=y > CONFIG_CMD_LICENSE=y > @@ -96,6 +96,7 @@ CONFIG_CMD_CRAMFS=y > CONFIG_CMD_EXT4_WRITE=y > CONFIG_CMD_SQUASHFS=y > CONFIG_CMD_MTDPARTS=y > +CONFIG_CMD_STACKPROTECTOR_TEST=y > CONFIG_MAC_PARTITION=y > CONFIG_AMIGA_PARTITION=y > CONFIG_OF_CONTROL=y > @@ -131,6 +132,7 @@ CONFIG_CPU=y > CONFIG_DM_DEMO=y > CONFIG_DM_DEMO_SIMPLE=y > CONFIG_DM_DEMO_SHAPE=y > +CONFIG_DFU_SF=y > CONFIG_DMA=y > CONFIG_DMA_CHANNELS=y > CONFIG_SANDBOX_DMA=y > @@ -269,14 +271,12 @@ CONFIG_CMD_DHRYSTONE=y > CONFIG_TPM=y > CONFIG_LZ4=y > CONFIG_ERRNO_STR=y > +CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y > +CONFIG_EFI_CAPSULE_ON_DISK=y > +CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y > +CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y > CONFIG_EFI_SECURE_BOOT=y > CONFIG_TEST_FDTDEC=y > CONFIG_UNIT_TEST=y > CONFIG_UT_TIME=y > CONFIG_UT_DM=y > -# > -CONFIG_DFU_SF=y > -CONFIG_EFI_RUNTIME_UPDATE_CAPSULE=y > -CONFIG_EFI_CAPSULE_ON_DISK=y > -CONFIG_EFI_CAPSULE_FIRMWARE_FIT=y > -CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y > diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl > index 87021e2..6725201 100644 > --- a/scripts/Makefile.spl > +++ b/scripts/Makefile.spl > @@ -67,6 +67,12 @@ include $(srctree)/scripts/Makefile.lib > KBUILD_CFLAGS += -ffunction-sections -fdata-sections > LDFLAGS_FINAL += --gc-sections > > +ifeq ($(CONFIG_$(SPL_TPL_)STACKPROTECTOR),y) > +KBUILD_CFLAGS += -fstack-protector-strong > +else > +KBUILD_CFLAGS += -fno-stack-protector > +endif > + > # FIX ME > cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \ > $(NOSTDINC_FLAGS) > diff --git a/test/py/tests/test_stackprotector.py b/test/py/tests/test_stackprotector.py > new file mode 100644 > index 0000000..7aeec5e > --- /dev/null > +++ b/test/py/tests/test_stackprotector.py > @@ -0,0 +1,15 @@ > +# SPDX-License-Identifier: GPL-2.0 > +# Copyright (c) 2021 Broadcom > + > +import pytest > +import signal > + > +@pytest.mark.buildconfigspec('cmd_stackprotector_test') > +def test_stackprotector(u_boot_console): > + """Test that the stackprotector function works.""" > + > + u_boot_console.run_command('stackprot_test',wait_for_prompt=False) > + expected_response = 'Stack smashing detected' > + u_boot_console.wait_for(expected_response) > + u_boot_console.restart_uboot() > + >
On Sat, Apr 10, 2021 at 12:11:33PM +0200, Heinrich Schuchardt wrote:
On 4/10/21 12:27 AM, Joel Peshkin wrote:
Hi Heinrich,
Has there been any progress in getting the EFI erors fixed so that this can be committed? There seems to be little point in my refreshing this patch until that is done.
I have fixed up your patch to work with EFI and will add it to my next pull request.
If all of CI now works with -fstack-protector enabled, I'll take it up in my tree.
participants (4)
-
Alex Sadovsky -
Heinrich Schuchardt -
Joel Peshkin -
Tom Rini