3.16.62-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet edumazet@google.com
commit bbd6528d28c1b8e80832b3b018ec402b6f5c3215 upstream.
In the unlikely case ip6_xmit() has to call skb_realloc_headroom(), we need to call skb_set_owner_w() before consuming original skb, otherwise we risk a use-after-free.
Bring IPv6 in line with what we do in IPv4 to fix this.
Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet edumazet@google.com Reported-by: syzbot syzkaller@googlegroups.com Signed-off-by: David S. Miller davem@davemloft.net [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -183,9 +183,10 @@ int ip6_xmit(struct sock *sk, struct sk_ kfree_skb(skb); return -ENOBUFS; } + if (skb->sk) + skb_set_owner_w(skb2, skb->sk); consume_skb(skb); skb = skb2; - skb_set_owner_w(skb, sk); } if (opt->opt_flen) ipv6_push_frag_opts(skb, opt, &proto);