vrf: Fix use after free and double free in vrf_finish_output
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>
diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index 139c61c..ac40924 100644
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -578,12 +578,13 @@
if (!IS_ERR(neigh)) {
sock_confirm_neigh(skb, neigh);
ret = neigh_output(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;
}
