From: Kees Cook <keescook@xxxxxxxxxxxx>
[ Upstream commit 9380ce246a052a1e00121cd480028b6907aeae38 ]
Commit 8d58f222e85f ("ubsan: disable UBSAN_ALIGNMENT under
COMPILE_TEST") tried to fix the pathological results of UBSAN_ALIGNMENT
with UBSAN_TRAP (which objtool would rightly scream about), but it made
an assumption about how COMPILE_TEST gets set (it is not set for
randconfig). As a result, we need a bigger hammer here: just don't
allow the alignment checks with the trap mode.
Fixes: 8d58f222e85f ("ubsan: disable UBSAN_ALIGNMENT under COMPILE_TEST")
Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Acked-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Elena Petrova <lenaptr@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/202005291236.000FCB6@keescook
Link: https://lore.kernel.org/lkml/742521db-1e8c-0d7a-1ed4-a908894fb497@xxxxxxxxxxxxx/
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
lib/Kconfig.ubsan | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/Kconfig.ubsan b/lib/Kconfig.ubsan
index 929211039bac..27bcc2568c95 100644
--- a/lib/Kconfig.ubsan
+++ b/lib/Kconfig.ubsan
@@ -63,7 +63,7 @@ config UBSAN_SANITIZE_ALL
config UBSAN_ALIGNMENT
bool "Enable checks for pointers alignment"
default !HAVE_EFFICIENT_UNALIGNED_ACCESS
- depends on !X86 || !COMPILE_TEST
+ depends on !UBSAN_TRAP
help
This option enables the check of unaligned memory accesses.
Enabling this option on architectures that support unaligned
--
2.25.1
