From 20422a48839b1c869f014f7649cd1522c968d793 Mon Sep 17 00:00:00 2001 From: David Gstir Date: Sun, 15 Nov 2015 17:14:42 +0100 Subject: [PATCH] crypto: talitos - Fix timing leak in ESP ICV verification commit 79960943fdc114fd4583c9ab164b5c89da7aa601 upstream. Using non-constant time memcmp() makes the verification of the authentication tag in the decrypt path vulnerable to timing attacks. Fix this by using crypto_memneq() instead. Signed-off-by: David Gstir Signed-off-by: Herbert Xu [ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques --- drivers/crypto/talitos.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c index 307931528eb2..da328ed633fb 100644 --- a/drivers/crypto/talitos.c +++ b/drivers/crypto/talitos.c @@ -870,8 +870,8 @@ static void ipsec_esp_decrypt_swauth_done(struct device *dev, icvdata = &edesc->link_tbl[0]; sg = sg_last(req->dst, edesc->dst_nents ? : 1); - err = memcmp(icvdata, (char *)sg_virt(sg) + sg->length - - ctx->authsize, ctx->authsize) ? -EBADMSG : 0; + err = crypto_memneq(icvdata, (char *)sg_virt(sg) + sg->length - + ctx->authsize, ctx->authsize) ? -EBADMSG : 0; } kfree(edesc);