From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752019Ab2JFFKk (ORCPT ); Sat, 6 Oct 2012 01:10:40 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:63595 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750835Ab2JFFKf (ORCPT ); Sat, 6 Oct 2012 01:10:35 -0400 From: ramesh.nagappa@gmail.com To: netdev@vger.kernel.org Cc: davem@davemloft.net, edumazet@google.com, ebiederm@xmission.com, xemul@parallels.com, linux-kernel@vger.kernel.org, Ramesh Nagappa Subject: [PATCH V2] net: Fix skb_under_panic oops in neigh_resolve_output Date: Fri, 5 Oct 2012 22:10:15 -0700 Message-Id: <1349500215-22765-1-git-send-email-ramesh.nagappa@gmail.com> X-Mailer: git-send-email 1.7.11.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The retry loop in neigh_resolve_output() and neigh_connected_output() call dev_hard_header() with out reseting the skb to network_header. This causes the retry to fail with skb_under_panic. The fix is to reset the network_header within the retry loop. Signed-off-by: Ramesh Nagappa Reviewed-by: Shawn Lu Reviewed-by: Robert Coulson Reviewed-by: Billie Alsup --- net/core/neighbour.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 117afaf..058bb1e 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -1301,8 +1301,6 @@ int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb) if (!dst) goto discard; - __skb_pull(skb, skb_network_offset(skb)); - if (!neigh_event_send(neigh, skb)) { int err; struct net_device *dev = neigh->dev; @@ -1312,6 +1310,7 @@ int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb) neigh_hh_init(neigh, dst); do { + __skb_pull(skb, skb_network_offset(skb)); seq = read_seqbegin(&neigh->ha_lock); err = dev_hard_header(skb, dev, ntohs(skb->protocol), neigh->ha, NULL, skb->len); @@ -1342,9 +1341,8 @@ int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb) unsigned int seq; int err; - __skb_pull(skb, skb_network_offset(skb)); - do { + __skb_pull(skb, skb_network_offset(skb)); seq = read_seqbegin(&neigh->ha_lock); err = dev_hard_header(skb, dev, ntohs(skb->protocol), neigh->ha, NULL, skb->len); -- 1.7.11.4