[U-Boot] [PATCH] efi_selftest: check for buffer overflow in efi_get_variable

Check if GetVariable writes past the end of the output data buffer.
Signed-off-by: Ivan Gorinov ivan.gorinov@intel.com --- lib/efi_selftest/efi_selftest_variables.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/lib/efi_selftest/efi_selftest_variables.c b/lib/efi_selftest/efi_selftest_variables.c index f5e8eb6..8a02dbc 100644 --- a/lib/efi_selftest/efi_selftest_variables.c +++ b/lib/efi_selftest/efi_selftest_variables.c @@ -72,6 +72,22 @@ static int execute(void) efi_st_error("SetVariable failed\n"); return EFI_ST_FAILURE; } + data[3] = 0xff; + len = 3; + ret = runtime->get_variable(L"efi_st_var0", &guid_vendor0, + &attr, &len, data); + if (ret != EFI_SUCCESS) { + efi_st_error("GetVariable failed\n"); + return EFI_ST_FAILURE; + } + if (efi_st_memcmp(data, v + 4, 3)) { + efi_st_error("GetVariable returned wrong value\n"); + return EFI_ST_FAILURE; + } + if (data[3] != 0xff) { + efi_st_error("GetVariable wrote past the end of the buffer\n"); + return EFI_ST_FAILURE; + } /* Set variable 1 */ ret = runtime->set_variable(L"efi_st_var1", &guid_vendor1, EFI_VARIABLE_BOOTSERVICE_ACCESS,

On 05/25/2018 02:09 AM, Ivan Gorinov wrote:
Check if GetVariable writes past the end of the output data buffer.
Signed-off-by: Ivan Gorinov ivan.gorinov@intel.com
The patch produces build warnings:
lib/efi_selftest/efi_selftest_variables.c: In function ‘execute’: lib/efi_selftest/efi_selftest_variables.c:75:10: warning: assignment makes pointer from integer without a cast [-Wint-conversion] data[3] = 0xff; ^ lib/efi_selftest/efi_selftest_variables.c:87:14: warning: comparison between pointer and integer if (data[3] != 0xff) {
This is due to an inappropriate definition in my prior patch. Could you, please, add this change:
-u8 *data[EFI_ST_MAX_DATA_SIZE]; +u8 data[EFI_ST_MAX_DATA_SIZE];
Otherwise your patch is fine.
Best regards
Heinrich
lib/efi_selftest/efi_selftest_variables.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/lib/efi_selftest/efi_selftest_variables.c b/lib/efi_selftest/efi_selftest_variables.c index f5e8eb6..8a02dbc 100644 --- a/lib/efi_selftest/efi_selftest_variables.c +++ b/lib/efi_selftest/efi_selftest_variables.c @@ -72,6 +72,22 @@ static int execute(void) efi_st_error("SetVariable failed\n"); return EFI_ST_FAILURE; }
- data[3] = 0xff;
- len = 3;
- ret = runtime->get_variable(L"efi_st_var0", &guid_vendor0,
&attr, &len, data);
- if (ret != EFI_SUCCESS) {
efi_st_error("GetVariable failed\n");
return EFI_ST_FAILURE;
- }
- if (efi_st_memcmp(data, v + 4, 3)) {
efi_st_error("GetVariable returned wrong value\n");
return EFI_ST_FAILURE;
- }
- if (data[3] != 0xff) {
efi_st_error("GetVariable wrote past the end of the buffer\n");
return EFI_ST_FAILURE;
- } /* Set variable 1 */ ret = runtime->set_variable(L"efi_st_var1", &guid_vendor1, EFI_VARIABLE_BOOTSERVICE_ACCESS,
participants (2)
-
Heinrich Schuchardt
-
Ivan Gorinov