Subject: [PATCH net] ipv6: fix possible mem leaks in ipv6_make_skb()

From: Eric Dumazet <[email-masked]>
Date: Wed, 10 Jan 2018 03:45:49 -0800

From: Eric Dumazet <[email-masked]>

ip6_setup_cork() might return an error, while memory allocations have
been done and must be rolled back.

Fixes: 6422398c2ab0 ("ipv6: introduce ipv6_make_skb")
Signed-off-by: Eric Dumazet <[email-masked]>
Cc: Vlad Yasevich <[email-masked]>
Reported-by: Mike Maloney <[email-masked]>
---
 net/ipv6/ip6_output.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index f7dd51c4231415fd1321fd431194d896ea2d1689..688ba5f7516b37c87b879036dce781bdcfa01739 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1735,9 +1735,10 @@ struct sk_buff *ip6_make_skb(struct sock *sk,
 	cork.base.opt = NULL;
 	v6_cork.opt = NULL;
 	err = ip6_setup_cork(sk, &cork, &v6_cork, ipc6, rt, fl6);
-	if (err)
+	if (err) {
+		ip6_cork_release(&cork, &v6_cork);
 		return ERR_PTR(err);
-
+	}
 	if (ipc6->dontfrag < 0)
 		ipc6->dontfrag = inet6_sk(sk)->dontfrag;