diff options
| author | Eric Dumazet <edumazet@google.com> | 2017-02-05 20:23:22 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-02-18 15:11:41 +0100 |
| commit | 1e340bb22af3afc881db78c17b73eaf3d26fb8fe (patch) | |
| tree | 933da44e1f1594050e3d326803fa85f227fb177b /net | |
| parent | ae1768bbbc469b75662c6714957fe5886cc960c4 (diff) | |
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>
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 b9f1fee9a886..e5ee107a0575 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -987,6 +987,16 @@ 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, @@ -1178,8 +1188,10 @@ 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); + } } } @@ -1194,16 +1206,6 @@ 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. * |