diff options
| author | Eric Dumazet <edumazet@google.com> | 2017-02-05 20:23:22 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-02-06 10:52:45 -0500 |
| commit | ebf6c9cb23d7e56eec8575a88071dec97ad5c6e2 (patch) | |
| tree | 408df47ccbf5f9ee7d12dcf9f9583b18ff0a2b30 /net | |
| parent | 7892032cfe67f4bde6fc2ee967e45a8fbaf33756 (diff) | |
ipv6: tcp: add a missing tcp_v6_restore_cb()
Dmitry reported use-after-free in ip6_datagram_recv_specific_ctl()
A similar bug was fixed in commit 8ce48623f0cf ("ipv6: tcp: restore
IP6CB for pktoptions skbs"), but I missed another spot.
tcp_v6_syn_recv_sock() can indeed set np->pktoptions from ireq->pktopts
Fixes: 971f10eca186 ("tcp: better TCP_SKB_CB layout to reduce cache line misses")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv6/tcp_ipv6.c | 24 |
1 files changed, 13 insertions, 11 deletions
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index cb8929681dc7..eaad72c3d746 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -991,6 +991,16 @@ drop: return 0; /* don't send reset */ } +static void tcp_v6_restore_cb(struct sk_buff *skb) +{ + /* We need to move header back to the beginning if xfrm6_policy_check() + * and tcp_v6_fill_cb() are going to be called again. + * ip6_datagram_recv_specific_ctl() also expects IP6CB to be there. + */ + memmove(IP6CB(skb), &TCP_SKB_CB(skb)->header.h6, + sizeof(struct inet6_skb_parm)); +} + static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, struct request_sock *req, struct dst_entry *dst, @@ -1182,8 +1192,10 @@ static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff * sk_gfp_mask(sk, GFP_ATOMIC)); consume_skb(ireq->pktopts); ireq->pktopts = NULL; - if (newnp->pktoptions) + if (newnp->pktoptions) { + tcp_v6_restore_cb(newnp->pktoptions); skb_set_owner_r(newnp->pktoptions, newsk); + } } } @@ -1198,16 +1210,6 @@ out: return NULL; } -static void tcp_v6_restore_cb(struct sk_buff *skb) -{ - /* We need to move header back to the beginning if xfrm6_policy_check() - * and tcp_v6_fill_cb() are going to be called again. - * ip6_datagram_recv_specific_ctl() also expects IP6CB to be there. - */ - memmove(IP6CB(skb), &TCP_SKB_CB(skb)->header.h6, - sizeof(struct inet6_skb_parm)); -} - /* The socket must have it's spinlock held when we get * here, unless it is a TCP_LISTEN socket. * |