Add the basic infrastructure for declaring fuzz tests and a command to invoke them.
Signed-off-by: Andrew Scull ascull@google.com Reviewed-by: Simon Glass sjg@chromium.org --- Kconfig | 9 +++++ include/test/fuzz.h | 51 +++++++++++++++++++++++++++ test/Makefile | 1 + test/fuzz/Makefile | 7 ++++ test/fuzz/cmd_fuzz.c | 82 ++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 150 insertions(+) create mode 100644 include/test/fuzz.h create mode 100644 test/fuzz/Makefile create mode 100644 test/fuzz/cmd_fuzz.c
diff --git a/Kconfig b/Kconfig index a2577bcce6..1d472a7862 100644 --- a/Kconfig +++ b/Kconfig @@ -161,6 +161,15 @@ config ASAN Enables AddressSanitizer to discover out-of-bounds accesses, use-after-free, double-free and memory leaks.
+config FUZZ + bool "Enable fuzzing" + depends on CC_IS_CLANG + depends on DM_FUZZING_ENGINE + select ASAN + help + Enables the fuzzing infrastructure to generate fuzzing data and run + fuzz tests. + config CC_HAS_ASM_INLINE def_bool $(success,echo 'void foo(void) { asm inline (""); }' | $(CC) -x c - -c -o /dev/null)
diff --git a/include/test/fuzz.h b/include/test/fuzz.h new file mode 100644 index 0000000000..d4c57540eb --- /dev/null +++ b/include/test/fuzz.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (c) 2022 Google, Inc. + * Written by Andrew Scull ascull@google.com + */ + +#ifndef __TEST_FUZZ_H +#define __TEST_FUZZ_H + +#include <linker_lists.h> +#include <linux/types.h> + +/** + * struct fuzz_test - Information about a fuzz test + * + * @name: Name of fuzz test + * @func: Function to call to perform fuzz test on an input + * @flags: Flags indicate pre-conditions for fuzz test + */ +struct fuzz_test { + const char *name; + int (*func)(const uint8_t * data, size_t size); + int flags; +}; + +/** + * FUZZ_TEST() - register a fuzz test + * + * The fuzz test function must return 0 as other values are reserved for future + * use. + * + * @_name: the name of the fuzz test function + * @_flags: an integer field that can be evaluated by the fuzzer + * implementation + */ +#define FUZZ_TEST(_name, _flags) \ + ll_entry_declare(struct fuzz_test, _name, fuzz_tests) = { \ + .name = #_name, \ + .func = _name, \ + .flags = _flags, \ + } + +/** Get the start of the list of fuzz tests */ +#define FUZZ_TEST_START() \ + ll_entry_start(struct fuzz_test, fuzz_tests) + +/** Get the number of elements in the list of fuzz tests */ +#define FUZZ_TEST_COUNT() \ + ll_entry_count(struct fuzz_test, fuzz_tests) + +#endif /* __TEST_FUZZ_H */ diff --git a/test/Makefile b/test/Makefile index b3b2902e2e..bb2b0b5c73 100644 --- a/test/Makefile +++ b/test/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_$(SPL_)CMDLINE) += cmd_ut.o obj-$(CONFIG_$(SPL_)CMDLINE) += command_ut.o obj-$(CONFIG_$(SPL_)UT_COMPRESSION) += compression.o obj-y += dm/ +obj-$(CONFIG_FUZZ) += fuzz/ obj-$(CONFIG_$(SPL_)CMDLINE) += print_ut.o obj-$(CONFIG_$(SPL_)CMDLINE) += str_ut.o obj-$(CONFIG_UT_TIME) += time_ut.o diff --git a/test/fuzz/Makefile b/test/fuzz/Makefile new file mode 100644 index 0000000000..03eeeeb497 --- /dev/null +++ b/test/fuzz/Makefile @@ -0,0 +1,7 @@ +# SPDX-License-Identifier: GPL-2.0+ +# +# Copyright (c) 2022 Google, Inc. +# Written by Andrew Scull ascull@google.com +# + +obj-$(CONFIG_$(SPL_)CMDLINE) += cmd_fuzz.o diff --git a/test/fuzz/cmd_fuzz.c b/test/fuzz/cmd_fuzz.c new file mode 100644 index 0000000000..0cc01dc199 --- /dev/null +++ b/test/fuzz/cmd_fuzz.c @@ -0,0 +1,82 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (c) 2022 Google, Inc. + * Written by Andrew Scull ascull@google.com + */ + +#include <command.h> +#include <common.h> +#include <dm.h> +#include <fuzzing_engine.h> +#include <test/fuzz.h> + +static struct fuzz_test *find_fuzz_test(const char *name) +{ + struct fuzz_test *fuzzer = FUZZ_TEST_START(); + size_t count = FUZZ_TEST_COUNT(); + size_t i; + + for (i = 0; i < count; ++i) { + if (strcmp(name, fuzzer->name) == 0) + return fuzzer; + ++fuzzer; + } + + return NULL; +} + +static struct udevice *find_fuzzing_engine(void) +{ + struct udevice *dev; + + if (uclass_first_device(UCLASS_FUZZING_ENGINE, &dev)) + return NULL; + + return dev; +} + +static int do_fuzz(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) +{ + struct fuzz_test *fuzzer; + struct udevice *dev; + + if (argc != 2) + return CMD_RET_USAGE; + + fuzzer = find_fuzz_test(argv[1]); + if (!fuzzer) { + printf("Could not find fuzzer: %s\n", argv[1]); + return 1; + } + + dev = find_fuzzing_engine(); + if (!dev) { + puts("No fuzzing engine available\n"); + return 1; + } + + while (1) { + const uint8_t *data; + size_t size; + + if (dm_fuzzing_engine_get_input(dev, &data, &size)) { + puts("Fuzzing engine failed\n"); + return 1; + } + + fuzzer->func(data, size); + } + + return 1; +} + +#ifdef CONFIG_SYS_LONGHELP +static char fuzz_help_text[] = + "[fuzz-test-name] - execute the named fuzz test\n" + ; +#endif /* CONFIG_SYS_LONGHELP */ + +U_BOOT_CMD( + fuzz, CONFIG_SYS_MAXARGS, 1, do_fuzz, + "fuzz tests", fuzz_help_text +);