diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2019-04-03 09:39:50 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2019-04-03 11:02:24 +0200 |
| commit | 57b78a62e7f23c4686fe54091cdc3d12e60d6513 (patch) | |
| tree | d8ac655da75b7a72365c7226b93e78c06d0c9204 /mm/kasan/Makefile | |
| parent | a936af8ea3580855adcc80daa8e01c0196afeb15 (diff) | |
x86/uaccess, kasan: Fix KASAN vs SMAP
KASAN inserts extra code for every LOAD/STORE emitted by te compiler.
Much of this code is simple and safe to run with AC=1, however the
kasan_report() function, called on error, is most certainly not safe
to call with AC=1.
Therefore wrap kasan_report() in user_access_{save,restore}; which for
x86 SMAP, saves/restores EFLAGS and clears AC before calling the real
function.
Also ensure all the functions are without __fentry__ hook. The
function tracer is also not safe.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'mm/kasan/Makefile')
| -rw-r--r-- | mm/kasan/Makefile | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/mm/kasan/Makefile b/mm/kasan/Makefile index 5d1065efbd47..613dfe681e9f 100644 --- a/mm/kasan/Makefile +++ b/mm/kasan/Makefile @@ -2,11 +2,13 @@ KASAN_SANITIZE := n UBSAN_SANITIZE_common.o := n UBSAN_SANITIZE_generic.o := n +UBSAN_SANITIZE_generic_report.o := n UBSAN_SANITIZE_tags.o := n KCOV_INSTRUMENT := n CFLAGS_REMOVE_common.o = -pg CFLAGS_REMOVE_generic.o = -pg +CFLAGS_REMOVE_generic_report.o = -pg CFLAGS_REMOVE_tags.o = -pg # Function splitter causes unnecessary splits in __asan_load1/__asan_store1 @@ -14,6 +16,7 @@ CFLAGS_REMOVE_tags.o = -pg CFLAGS_common.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) CFLAGS_generic.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) +CFLAGS_generic_report.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) CFLAGS_tags.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) obj-$(CONFIG_KASAN) := common.o init.o report.o |