Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752854Ab3F1Sy4 (ORCPT ); Fri, 28 Jun 2013 14:54:56 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:41660 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751687Ab3F1Syy (ORCPT ); Fri, 28 Jun 2013 14:54:54 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Eric Dumazet , "David S. Miller" , Kamal Mostafa Subject: [PATCH 074/105] ip_tunnel: fix kernel panic with icmp_dest_unreach Date: Fri, 28 Jun 2013 11:51:36 -0700 Message-Id: <1372445527-24414-75-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1372445527-24414-1-git-send-email-kamal@canonical.com> References: <1372445527-24414-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2956 Lines: 83 3.8.13.4 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit a622260254ee481747cceaaa8609985b29a31565 ] Daniel Petre reported crashes in icmp_dst_unreach() with following call graph: Daniel found a similar problem mentioned in http://lkml.indiana.edu/hypermail/linux/kernel/1007.0/00961.html And indeed this is the root cause : skb->cb[] contains data fooling IP stack. We must clear IPCB in ip_tunnel_xmit() sooner in case dst_link_failure() is called. Or else skb->cb[] might contain garbage from GSO segmentation layer. A similar fix was tested on linux-3.9, but gre code was refactored in linux-3.10. I'll send patches for stable kernels as well. Many thanks to Daniel for providing reports, patches and testing ! Reported-by: Daniel Petre Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Kamal Mostafa --- net/ipv4/ip_gre.c | 2 +- net/ipv4/ipip.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index a85062b..e0c1929 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -767,6 +767,7 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev tiph = &tunnel->parms.iph; } + memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); if ((dst = tiph->daddr) == 0) { /* NBMA tunnel */ @@ -912,7 +913,6 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev skb_push(skb, gre_hlen); skb_reset_network_header(skb); skb_set_transport_header(skb, sizeof(*iph)); - memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | IPSKB_REROUTED); skb_dst_drop(skb); diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c index 191fc24..b3fc09d 100644 --- a/net/ipv4/ipip.c +++ b/net/ipv4/ipip.c @@ -489,6 +489,7 @@ static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) if (tos & 1) tos = old_iph->tos; + memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); if (!dst) { /* NBMA tunnel */ if ((rt = skb_rtable(skb)) == NULL) { @@ -571,7 +572,6 @@ static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) skb->transport_header = skb->network_header; skb_push(skb, sizeof(struct iphdr)); skb_reset_network_header(skb); - memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | IPSKB_REROUTED); skb_dst_drop(skb); -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/