diff options
| author | Eric Dumazet <edumazet@google.com> | 2018-09-14 12:02:31 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-10-13 09:09:23 +0200 |
| commit | 2e421bf4b9632dfd0a39edfa6d362f3de4461065 (patch) | |
| tree | 39c52202f8b4c159768fe003faa27062885fd46e /net/ipv6 | |
| parent | 3f0d9d15b163049af09ac66cd2a25d103307cd06 (diff) | |
ipv6: fix possible use-after-free in ip6_xmit()
[ Upstream commit bbd6528d28c1b8e80832b3b018ec402b6f5c3215 ]
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/ip6_output.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 087fe616bfaf..0c344ca515ab 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -183,9 +183,10 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, 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); |