diff options
| author | Kees Cook <keescook@chromium.org> | 2023-05-30 17:34:15 -0700 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2023-06-01 11:24:51 -0700 |
| commit | 4ce1e94175696b8f5f6fa29f09f7ef56724ddc2a (patch) | |
| tree | 950a7a28ba09ec59aac330dd80477686273515c5 /arch/s390 | |
| parent | 91218d7d708ed2f4b77323ca70a948b8334dd767 (diff) | |
s390/purgatory: Do not use fortified string functions
With the addition of -fstrict-flex-arrays=3, struct sha256_state's
trailing array is no longer ignored by CONFIG_FORTIFY_SOURCE:
struct sha256_state {
u32 state[SHA256_DIGEST_SIZE / 4];
u64 count;
u8 buf[SHA256_BLOCK_SIZE];
};
This means that the memcpy() calls with "buf" as a destination in
sha256.c's code will attempt to perform run-time bounds checking, which
could lead to calling missing functions, specifically a potential
WARN_ONCE, which isn't callable from purgatory.
Reported-by: Thorsten Leemhuis <linux@leemhuis.info>
Closes: https://lore.kernel.org/lkml/175578ec-9dec-7a9c-8d3a-43f24ff86b92@leemhuis.info/
Bisected-by: "Joan Bruguera Micó" <joanbrugueram@gmail.com>
Fixes: df8fc4e934c1 ("kbuild: Enable -fstrict-flex-arrays=3")
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Linux Kernel Functional Testing <lkft@linaro.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: linux-s390@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20230531003414.never.050-kees@kernel.org
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/purgatory/Makefile | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/s390/purgatory/Makefile b/arch/s390/purgatory/Makefile index 32573b4f9bd2..cf14740abd1c 100644 --- a/arch/s390/purgatory/Makefile +++ b/arch/s390/purgatory/Makefile @@ -10,7 +10,7 @@ PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y)) $(obj)/sha256.o: $(srctree)/lib/crypto/sha256.c FORCE $(call if_changed_rule,cc_o_c) -CFLAGS_sha256.o := -D__DISABLE_EXPORTS +CFLAGS_sha256.o := -D__DISABLE_EXPORTS -D__NO_FORTIFY $(obj)/mem.o: $(srctree)/arch/s390/lib/mem.S FORCE $(call if_changed_rule,as_o_S) |