From: Alexander Potapenko <glider@xxxxxxxxxx> As a code-size optimization, LLVM builds since r279383 may bulk-manipulate the shadow region when (un)poisoning large memory blocks. This requires new callbacks that simply do an uninstrumented memset(). This fixes linking the Clang-built kernel when using KASAN. Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx> [ghackmann@xxxxxxxxxx: fix memset() parameters, and tweak commit message to describe new callbacks] Signed-off-by: Greg Hackmann <ghackmann@xxxxxxxxxx> Signed-off-by: Paul Lawrence <paullawrence@xxxxxxxxxx> --- mm/kasan/kasan.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c index d96b36088b2f..8aaee42fcfab 100644 --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -770,6 +770,21 @@ void __asan_allocas_unpoison(const void *stack_top, const void *stack_bottom) } EXPORT_SYMBOL(__asan_allocas_unpoison); +/* Emitted by the compiler to [un]poison local variables. */ +#define DEFINE_ASAN_SET_SHADOW(byte) \ + void __asan_set_shadow_##byte(const void *addr, size_t size) \ + { \ + __memset((void *)addr, 0x##byte, size); \ + } \ + EXPORT_SYMBOL(__asan_set_shadow_##byte) + +DEFINE_ASAN_SET_SHADOW(00); +DEFINE_ASAN_SET_SHADOW(f1); +DEFINE_ASAN_SET_SHADOW(f2); +DEFINE_ASAN_SET_SHADOW(f3); +DEFINE_ASAN_SET_SHADOW(f5); +DEFINE_ASAN_SET_SHADOW(f8); + #ifdef CONFIG_MEMORY_HOTPLUG static int __meminit kasan_mem_notifier(struct notifier_block *nb, unsigned long action, void *data) -- 2.15.0.531.g2ccb3012c9-goog -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html