From: Herbert Xu Date: Wed, 4 May 2016 09:52:56 +0000 (+0800) Subject: crypto: hash - Fix page length clamping in hash walk X-Git-Tag: firefly_0821_release~176^2~4^2~45^2~30 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=3cbc5f6ed2722a65b75de22fe2206471f093b6c3;p=firefly-linux-kernel-4.4.55.git 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: Greg Kroah-Hartman --- diff --git a/crypto/ahash.c b/crypto/ahash.c index d19b52324cf5..dac1c24e9c3e 100644 --- a/crypto/ahash.c +++ b/crypto/ahash.c @@ -69,8 +69,9 @@ 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)