[PATCH v2] netfilter: release skbuf when nlmsg put fail

From: Houcheng Lin
Date: Tue Oct 14 2014 - 05:42:23 EST


When system is under heavy loading, the __nfulnl_send() may may failed
to put nlmsg into skbuf of nfulnl_instance. If not clear the skbuff on failed,
the __nfulnl_send() will still try to put next nlmsg onto this half-full skbuf
and cause the user program can never receive packet.

This patch fix this issue by releasing skbuf immediately after nlmst put
failed.

Signed-off-by: Houcheng Lin <houcheng@xxxxxxxxx>
---
net/netfilter/nfnetlink_log.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c
index a11c5ff..0ad5d32 100644
--- a/net/netfilter/nfnetlink_log.c
+++ b/net/netfilter/nfnetlink_log.c
@@ -353,15 +353,17 @@ __nfulnl_send(struct nfulnl_instance *inst)
NLMSG_DONE,
sizeof(struct nfgenmsg),
0);
- if (!nlh)
+ if (!nlh) {
+ WARN_ON(1);
+ kfree_skb(inst->skb);
goto out;
+ }
}
status = nfnetlink_unicast(inst->skb, inst->net, inst->peer_portid,
MSG_DONTWAIT);
-
+out:
inst->qlen = 0;
inst->skb = NULL;
-out:
return status;
}

--
1.7.9.5
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