diff options
author | Arnd Bergmann <[email protected]> | 2019-08-02 21:48:58 -0700 |
---|---|---|
committer | Linus Torvalds <[email protected]> | 2019-08-03 07:02:00 -0700 |
commit | af700eaed0564d5d3963a7a51cb0843629d7fe3d (patch) | |
tree | b87b821841584cc5cee7c360b687111b5b9e1f18 | |
parent | ebb6d35a74ce21ce1673b8f404c1039d5a1e7e2d (diff) |
ubsan: build ubsan.c more conservatively
objtool points out several conditions that it does not like, depending
on the combination with other configuration options and compiler
variants:
stack protector:
lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch()+0xbf: call to __stack_chk_fail() with UACCESS enabled
lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch_v1()+0xbe: call to __stack_chk_fail() with UACCESS enabled
stackleak plugin:
lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch()+0x4a: call to stackleak_track_stack() with UACCESS enabled
lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch_v1()+0x4a: call to stackleak_track_stack() with UACCESS enabled
kasan:
lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch()+0x25: call to memcpy() with UACCESS enabled
lib/ubsan.o: warning: objtool: __ubsan_handle_type_mismatch_v1()+0x25: call to memcpy() with UACCESS enabled
The stackleak and kasan options just need to be disabled for this file
as we do for other files already. For the stack protector, we already
attempt to disable it, but this fails on clang because the check is
mixed with the gcc specific -fno-conserve-stack option. According to
Andrey Ryabinin, that option is not even needed, dropping it here fixes
the stackprotector issue.
Link: http://lkml.kernel.org/r/[email protected]
Link: https://lore.kernel.org/lkml/[email protected]/t/
Link: https://lore.kernel.org/lkml/[email protected]/t/
Fixes: d08965a27e84 ("x86/uaccess, ubsan: Fix UBSAN vs. SMAP")
Signed-off-by: Arnd Bergmann <[email protected]>
Reviewed-by: Andrey Ryabinin <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dmitry Vyukov <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
-rw-r--r-- | lib/Makefile | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/lib/Makefile b/lib/Makefile index 095601ce371d..29c02a924973 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -279,7 +279,8 @@ obj-$(CONFIG_UCS2_STRING) += ucs2_string.o obj-$(CONFIG_UBSAN) += ubsan.o UBSAN_SANITIZE_ubsan.o := n -CFLAGS_ubsan.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) +KASAN_SANITIZE_ubsan.o := n +CFLAGS_ubsan.o := $(call cc-option, -fno-stack-protector) $(DISABLE_STACKLEAK_PLUGIN) obj-$(CONFIG_SBITMAP) += sbitmap.o |