From 201941360944afbde6ab6f5ff70f96f16d334971 Mon Sep 17 00:00:00 2001 From: Steffen Klassert Date: Fri, 5 Jan 2018 08:35:47 +0100 Subject: [PATCH] esp: Fix GRO when the headers not fully in the linear part of the skb. commit 374d1b5a81f7f9cc5e7f095ac3d5aff3f6600376 upstream. The GRO layer does not necessarily pull the complete headers into the linear part of the skb, a part may remain on the first page fragment. This can lead to a crash if we try to pull the headers, so make sure we have them on the linear part before pulling. Fixes: 7785bba299a8 ("esp: Add a software GRO codepath") Reported-by: syzbot+82bbd65569c49c6c0c4d@syzkaller.appspotmail.com Signed-off-by: Steffen Klassert Signed-off-by: Greg Kroah-Hartman --- net/ipv4/esp4_offload.c | 3 ++- net/ipv6/esp6_offload.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/net/ipv4/esp4_offload.c b/net/ipv4/esp4_offload.c index 56c49623bb9d..29b333a62ab0 100644 --- a/net/ipv4/esp4_offload.c +++ b/net/ipv4/esp4_offload.c @@ -38,7 +38,8 @@ static struct sk_buff **esp4_gro_receive(struct sk_buff **head, __be32 spi; int err; - skb_pull(skb, offset); + if (!pskb_pull(skb, offset)) + return NULL; if ((err = xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq)) != 0) goto out; diff --git a/net/ipv6/esp6_offload.c b/net/ipv6/esp6_offload.c index 1ea9d794447e..f52c314d4c97 100644 --- a/net/ipv6/esp6_offload.c +++ b/net/ipv6/esp6_offload.c @@ -60,7 +60,8 @@ static struct sk_buff **esp6_gro_receive(struct sk_buff **head, int nhoff; int err; - skb_pull(skb, offset); + if (!pskb_pull(skb, offset)) + return NULL; if ((err = xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq)) != 0) goto out;