[PATCH 5.15 102/148] netfilter: ebtables: fix memory leak when blob is malformed

Greg Kroah-Hartman
2022-09-26T11:25:31Z

From: Florian Westphal <fw@strlen.de>

[ 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>
---
net/bridge/netfilter/ebtables.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 8905fe2fe023..16774559c52c 100644
--- 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;
--
2.35.1