From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Ramesh Nagappa , Shawn Lu , Robert Coulson , Billie Alsup , "David S. Miller" Subject: [ 66/85] net: Fix skb_under_panic oops in neigh_resolve_output Date: Thu, 25 Oct 2012 17:06:24 -0700 Message-Id: <20121026000037.757852824@linuxfoundation.org> In-Reply-To: <20121026000031.107227138@linuxfoundation.org> References: <20121026000031.107227138@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: "ramesh.nagappa@gmail.com" [ Upstream commit e1f165032c8bade3a6bdf546f8faf61fda4dd01c ] 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 Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/core/neighbour.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -1301,8 +1301,6 @@ int neigh_resolve_output(struct neighbou 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 neighbou 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 neighb 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);