From: Hyunwoo Kim <imv4bel@gmail.com>
Date: Sat, 7 Mar 2026 17:24:06 +0000 (+0900)
Subject: netfilter: nfnetlink_queue: fix entry leak in bridge verdict error path
X-Git-Tag: v7.0-rc4~37^2~5^2~2
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=f1ba83755d81c6fc66ac7acd723d238f974091e9;p=thirdparty%2Flinux.git

netfilter: nfnetlink_queue: fix entry leak in bridge verdict error path

nfqnl_recv_verdict() calls find_dequeue_entry() to remove the queue
entry from the queue data structures, taking ownership of the entry.
For PF_BRIDGE packets, it then calls nfqa_parse_bridge() to parse VLAN
attributes.  If nfqa_parse_bridge() returns an error (e.g. NFQA_VLAN
present but NFQA_VLAN_TCI missing), the function returns immediately
without freeing the dequeued entry or its sk_buff.

This leaks the nf_queue_entry, its associated sk_buff, and all held
references (net_device refcounts, struct net refcount).  Repeated
triggering exhausts kernel memory.

Fix this by dropping the entry via nfqnl_reinject() with NF_DROP verdict
on the error path, consistent with other error handling in this file.

Fixes: 8d45ff22f1b4 ("netfilter: bridge: nf queue verdict to use NFQA_VLAN and NFQA_L2HDR")
Reviewed-by: David Dull <monderasdor@gmail.com>
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
---

diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 7f5248b5f1ee..47f7f62906e2 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -1546,8 +1546,10 @@ static int nfqnl_recv_verdict(struct sk_buff *skb, const struct nfnl_info *info,
 
 	if (entry->state.pf == PF_BRIDGE) {
 		err = nfqa_parse_bridge(entry, nfqa);
-		if (err < 0)
+		if (err < 0) {
+			nfqnl_reinject(entry, NF_DROP);
 			return err;
+		}
 	}
 
 	if (nfqa[NFQA_PAYLOAD]) {