[PATCH net] ipv6: release dst on error in ip6_dst_lookup_tail

From: Willem de Bruijn <willemb@google.com>

If ip6_dst_lookup_tail has acquired a dst and fails the IPv4-mapped
check, release the dst before returning an error.

Fixes: b2e6f0c8dde5 ("ipv6: Inhibit IPv4-mapped src address on the wire.")
Signed-off-by: Willem de Bruijn <willemb@google.com>
---
 net/ipv6/ip6_output.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index e164684456df..7cebee58e55b 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c

@@ -1022,8 +1022,10 @@ static int ip6_dst_lookup_tail(struct net *net, const struct sock *sk,
 	}
 #endif
 	if (ipv6_addr_v4mapped(&fl6->saddr) &&
-	    !(ipv6_addr_v4mapped(&fl6->daddr) || ipv6_addr_any(&fl6->daddr)))
-		return -EAFNOSUPPORT;
+	    !(ipv6_addr_v4mapped(&fl6->daddr) || ipv6_addr_any(&fl6->daddr))) {
+		err = -EAFNOSUPPORT;
+		goto out_err_release;
+	}
 
 	return 0;
 

-- 
2.11.0.483.g087da7b7c-goog

On Sat, 2017-02-18 at 18:51 -0500, Willem de Bruijn wrote:

From: Willem de Bruijn <willemb@google.com>

If ip6_dst_lookup_tail has acquired a dst and fails the IPv4-mapped
check, release the dst before returning an error.

Fixes: b2e6f0c8dde5 ("ipv6: Inhibit IPv4-mapped src address on the wire.")
Signed-off-by: Willem de Bruijn <willemb@google.com>
---

Acked-by: Eric Dumazet <edumazet@google.com>

But looks like the commit sha1 was
ec5e3b0a1d41fbda0cc33a45bc9e54e91d9d12c7

So the correct tag would be

Fixes: ec5e3b0a1d41 ("ipv6: Inhibit IPv4-mapped src address on the wire.")

But looks like the commit sha1 was
ec5e3b0a1d41fbda0cc33a45bc9e54e91d9d12c7

So the correct tag would be

Fixes: ec5e3b0a1d41 ("ipv6: Inhibit IPv4-mapped src address on the wire.")

Thanks for catching that! I'll send a v2 with the fixed commit.