diff options
author | Eric Dumazet <edumazet@google.com> | 2017-02-06 07:23:22 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-04-18 08:55:44 +0300 |
commit | c12d69340ee7cd97da07cc8549b7f08bbaae71af (patch) | |
tree | e22ecbe7a6289ece167de8e2ff04769c009c977d | |
parent | 00f1069e680ec0311a5af1aa4f7ff77cecc90769 (diff) | |
download | linux-c12d69340ee7cd97da07cc8549b7f08bbaae71af.tar.xz |
ipv6: tcp: add a missing tcp_v6_restore_cb()
[ Upstream commit ebf6c9cb23d7e56eec8575a88071dec97ad5c6e2 ]
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-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 c1eefb612fb3..5b8a272422da 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1049,6 +1049,16 @@ 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(struct sock *sk, struct sk_buff *skb, struct request_sock *req, struct dst_entry *dst) @@ -1180,8 +1190,10 @@ static struct sock *tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb, sk_gfp_atomic(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); + } } newnp->opt = NULL; newnp->mcast_oif = tcp_v6_iif(skb); @@ -1250,16 +1262,6 @@ 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. * |