diff options
| author | David Ahern <dsahern@gmail.com> | 2018-03-29 12:49:52 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-04-13 19:50:27 +0200 |
| commit | 56f8ae4e07d2f9d1513ad79d5a44a2c2a29b5a67 (patch) | |
| tree | dc1035b73e2577d3b2d58681badeacc78631deb2 | |
| parent | d7d9a326879134129637eb1c570475b6cb5d90ae (diff) | |
vrf: Fix use after free and double free in vrf_finish_output
commit 82dd0d2a9a76fc8fa2b18d80b987d455728bf83a upstream.
Miguel reported an skb use after free / double free in vrf_finish_output
when neigh_output returns an error. The vrf driver should return after
the call to neigh_output as it takes over the skb on error path as well.
Patch is a simplified version of Miguel's patch which was written for 4.9,
and updated to top of tree.
Fixes: 8f58336d3f78a ("net: Add ethernet header for pass through VRF device")
Signed-off-by: Miguel Fadon Perlines <mfadon@teldat.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[ backport to 4.4 and 4.9 dropped the sock_confirm_neigh and
changed neigh_output to dst_neigh_output ]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/net/vrf.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c index ac945f8781ac..d3d59122a357 100644 --- a/drivers/net/vrf.c +++ b/drivers/net/vrf.c @@ -550,13 +550,15 @@ static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *s neigh = __ipv4_neigh_lookup_noref(dev, nexthop); if (unlikely(!neigh)) neigh = __neigh_create(&arp_tbl, &nexthop, dev, false); - if (!IS_ERR(neigh)) + if (!IS_ERR(neigh)) { ret = dst_neigh_output(dst, neigh, skb); + rcu_read_unlock_bh(); + return ret; + } rcu_read_unlock_bh(); err: - if (unlikely(ret < 0)) - vrf_tx_error(skb->dev, skb); + vrf_tx_error(skb->dev, skb); return ret; } |