netfilter: ebtables: fix memory leak when blob is malformed

[ Upstream commit 62ce44c4fff947eebdf10bb582267e686e6835c9 ]

The bug fix was incomplete, it "replaced" crash with a memory leak.
The old code had an assignment to "ret" embedded into the conditional,
restore this.

Fixes: 7997eff82828 ("netfilter: ebtables: reject blobs that don't provide all entry points")
Reported-and-tested-by: syzbot+a24c5252f3e3ab733464@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 9a0ae59cdc500b5e0d5883b1cfd085399350e61d..4f385d52a1c4961c024e41ade13ee75a1a015513 100644 (file)
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1040,8 +1040,10 @@ static int do_replace_finish(struct net *net, struct ebt_replace *repl,
                goto free_iterate;
        }
 
-       if (repl->valid_hooks != t->valid_hooks)
+       if (repl->valid_hooks != t->valid_hooks) {
+               ret = -EINVAL;
                goto free_unlock;
+       }
 
        if (repl->num_counters && repl->num_counters != t->private->nentries) {
                ret = -EINVAL;