From 342061ee4ef3d80001d1ae494378f3979c861dba Mon Sep 17 00:00:00 2001 From: Paul Lawrence Date: Tue, 6 Feb 2018 15:36:11 -0800 Subject: kasan: support alloca() poisoning clang's AddressSanitizer implementation adds redzones on either side of alloca()ed buffers. These redzones are 32-byte aligned and at least 32 bytes long. __asan_alloca_poison() is passed the size and address of the allocated buffer, *excluding* the redzones on either side. The left redzone will always be to the immediate left of this buffer; but AddressSanitizer may need to add padding between the end of the buffer and the right redzone. If there are any 8-byte chunks inside this padding, we should poison those too. __asan_allocas_unpoison() is just passed the top and bottom of the dynamic stack area, so unpoisoning is simpler. Link: http://lkml.kernel.org/r/20171204191735.132544-4-paullawrence@google.com Signed-off-by: Greg Hackmann Signed-off-by: Paul Lawrence Acked-by: Andrey Ryabinin Cc: Alexander Potapenko Cc: Dmitry Vyukov Cc: Masahiro Yamada Cc: Matthias Kaehlcke Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/Makefile.kasan | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Makefile.kasan b/scripts/Makefile.kasan index ab85095c3a75..3fb382c69ff6 100644 --- a/scripts/Makefile.kasan +++ b/scripts/Makefile.kasan @@ -32,7 +32,8 @@ else $(call cc-param,asan-globals=1) \ $(call cc-param,asan-instrumentation-with-call-threshold=$(call_threshold)) \ $(call cc-param,asan-stack=1) \ - $(call cc-param,asan-use-after-scope=1) + $(call cc-param,asan-use-after-scope=1) \ + $(call cc-param,asan-instrument-allocas=1) endif endif -- cgit v1.2.3-59-g8ed1b