diff options
| author | George Popescu | 2020-10-15 20:13:38 -0700 |
|---|---|---|
| committer | Linus Torvalds | 2020-10-16 11:11:22 -0700 |
| commit | 6a6155f664e31c9be43cd690541a9a682ba3dc22 (patch) | |
| tree | aefade86b74d129bd319a46ddc9241dd56d61cf3 /scripts | |
| parent | 5cf53f3ce3b9ff5321b56f9ed9d90d59307be7d0 (diff) | |
ubsan: introduce CONFIG_UBSAN_LOCAL_BOUNDS for Clang
When the kernel is compiled with Clang, -fsanitize=bounds expands to
-fsanitize=array-bounds and -fsanitize=local-bounds.
Enabling -fsanitize=local-bounds with Clang has the unfortunate
side-effect of inserting traps; this goes back to its original intent,
which was as a hardening and not a debugging feature [1]. The same
feature made its way into -fsanitize=bounds, but the traps remained. For
that reason, -fsanitize=bounds was split into 'array-bounds' and
'local-bounds' [2].
Since 'local-bounds' doesn't behave like a normal sanitizer, enable it
with Clang only if trapping behaviour was requested by
CONFIG_UBSAN_TRAP=y.
Add the UBSAN_BOUNDS_LOCAL config to Kconfig.ubsan to enable the
'local-bounds' option by default when UBSAN_TRAP is enabled.
[1] http://lists.llvm.org/pipermail/llvm-dev/2012-May/049972.html
[2] http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20131021/091536.html
Suggested-by: Marco Elver <elver@google.com>
Signed-off-by: George Popescu <georgepope@android.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Brazdil <dbrazdil@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lkml.kernel.org/r/20200922074330.2549523-1-georgepope@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'scripts')
| -rw-r--r-- | scripts/Makefile.ubsan | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/scripts/Makefile.ubsan b/scripts/Makefile.ubsan index 27348029b2b8..4e3fff0745e8 100644 --- a/scripts/Makefile.ubsan +++ b/scripts/Makefile.ubsan @@ -4,7 +4,15 @@ ifdef CONFIG_UBSAN_ALIGNMENT endif ifdef CONFIG_UBSAN_BOUNDS - CFLAGS_UBSAN += $(call cc-option, -fsanitize=bounds) + ifdef CONFIG_CC_IS_CLANG + CFLAGS_UBSAN += -fsanitize=array-bounds + else + CFLAGS_UBSAN += $(call cc-option, -fsanitize=bounds) + endif +endif + +ifdef CONFIG_UBSAN_LOCAL_BOUNDS + CFLAGS_UBSAN += -fsanitize=local-bounds endif ifdef CONFIG_UBSAN_MISC |