From 7581495ac82d6cb073609284c7f7186a48021d1e Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Fri, 5 May 2023 13:51:27 +1000 Subject: mm: kfence: fix false positives on big endian Since commit 1ba3cbf3ec3b ("mm: kfence: improve the performance of __kfence_alloc() and __kfence_free()"), kfence reports failures in random places at boot on big endian machines. The problem is that the new KFENCE_CANARY_PATTERN_U64 encodes the address of each byte in its value, so it needs to be byte swapped on big endian machines. The compiler is smart enough to do the le64_to_cpu() at compile time, so there is no runtime overhead. Link: https://lkml.kernel.org/r/20230505035127.195387-1-mpe@ellerman.id.au Fixes: 1ba3cbf3ec3b ("mm: kfence: improve the performance of __kfence_alloc() and __kfence_free()") Signed-off-by: Michael Ellerman Reviewed-by: Alexander Potapenko Reviewed-by: Marco Elver Cc: Peng Zhang Cc: David Laight Signed-off-by: Andrew Morton --- mm/kfence/kfence.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'mm/kfence') diff --git a/mm/kfence/kfence.h b/mm/kfence/kfence.h index 2aafc46a4aaf..392fb273e7bd 100644 --- a/mm/kfence/kfence.h +++ b/mm/kfence/kfence.h @@ -29,7 +29,7 @@ * canary of every 8 bytes is the same. 64-bit memory can be filled and checked * at a time instead of byte by byte to improve performance. */ -#define KFENCE_CANARY_PATTERN_U64 ((u64)0xaaaaaaaaaaaaaaaa ^ (u64)(0x0706050403020100)) +#define KFENCE_CANARY_PATTERN_U64 ((u64)0xaaaaaaaaaaaaaaaa ^ (u64)(le64_to_cpu(0x0706050403020100))) /* Maximum stack depth for reports. */ #define KFENCE_STACK_DEPTH 64 -- cgit