[PATCH 5.4 011/214] net/sched: act_ct: Fix skb double-free in tcf_ct_handle_fragments() error flow

Greg Kroah-Hartman
2020-09-01T16:35:17Z

From: Alaa Hleihel <alaa@mellanox.com>

[ Upstream commit eda814b97dfb8d9f4808eb2f65af9bd3705c4cae ]

tcf_ct_handle_fragments() shouldn't free the skb when ip_defrag() call
fails. Otherwise, we will cause a double-free bug.
In such cases, just return the error to the caller.

Fixes: b57dc7c13ea9 ("net/sched: Introduce action ct")
Signed-off-by: Alaa Hleihel <alaa@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/sched/act_ct.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/sched/act_ct.c
+++ b/net/sched/act_ct.c
@@ -186,7 +186,7 @@ static int tcf_ct_handle_fragments(struc
memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
err = nf_ct_frag6_gather(net, skb, user);
if (err && err != -EINPROGRESS)
- goto out_free;
+ return err;
#else
err = -EOPNOTSUPP;
goto out_free;