From b986834b2c37dbb9340adc8527734d9ec81e045e Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 4 May 2016 17:52:56 +0800 Subject: crypto: hash - Fix page length clamping in hash walk commit 13f4bb78cf6a312bbdec367ba3da044b09bf0e29 upstream. The crypto hash walk code is broken when supplied with an offset greater than or equal to PAGE_SIZE. This patch fixes it by adjusting walk->pg and walk->offset when this happens. Reported-by: Steffen Klassert Signed-off-by: Herbert Xu Signed-off-by: Ben Hutchings --- crypto/ahash.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'crypto') diff --git a/crypto/ahash.c b/crypto/ahash.c index 4f5e0eb3547f..8a25fdafa97f 100644 --- a/crypto/ahash.c +++ b/crypto/ahash.c @@ -68,8 +68,9 @@ static int hash_walk_new_entry(struct crypto_hash_walk *walk) struct scatterlist *sg; sg = walk->sg; - walk->pg = sg_page(sg); walk->offset = sg->offset; + walk->pg = sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT); + walk->offset = offset_in_page(walk->offset); walk->entrylen = sg->length; if (walk->entrylen > walk->total) -- cgit v1.2.3