From: Balasubramani Vivekanandan <balasubramani_vivekanandan@xxxxxxxxxx> Start address calculated for slab padding restoration was wrong. Wrong address would point to some section before padding and could cause corruption Signed-off-by: Balasubramani Vivekanandan <balasubramani_vivekanandan@xxxxxxxxxx> --- mm/slub.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index cfd56e5..733ba32 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -838,6 +838,7 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page) u8 *start; u8 *fault; u8 *end; + u8 *pad; int length; int remainder; @@ -851,8 +852,9 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page) if (!remainder) return 1; + pad = end - remainder; metadata_access_enable(); - fault = memchr_inv(end - remainder, POISON_INUSE, remainder); + fault = memchr_inv(pad, POISON_INUSE, remainder); metadata_access_disable(); if (!fault) return 1; @@ -860,9 +862,9 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page) end--; slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1); - print_section(KERN_ERR, "Padding ", end - remainder, remainder); + print_section(KERN_ERR, "Padding ", pad, remainder); - restore_bytes(s, "slab padding", POISON_INUSE, end - remainder, end); + restore_bytes(s, "slab padding", POISON_INUSE, fault, end); return 0; } -- 2.7.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
