diff options
| author | Willem de Bruijn <willemb@google.com> | 2017-09-26 12:20:17 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-10-12 11:51:22 +0200 |
| commit | 24ee394a82d2cd92c92b617713a4d263131a902b (patch) | |
| tree | c85d01dad43a809227211e7a8b5de424d0f5338a /net | |
| parent | 0f22167d3321a028c0b6edc2d5b2ab0e37a2ac53 (diff) | |
packet: only test po->has_vnet_hdr once in packet_snd
[ Upstream commit da7c9561015e93d10fe6aab73e9288e0d09d65a6 ]
Packet socket option po->has_vnet_hdr can be updated concurrently with
other operations if no ring is attached.
Do not test the option twice in packet_snd, as the value may change in
between calls. A race on setsockopt disable may cause a packet > mtu
to be sent without having GSO options set.
Fixes: bfd5f4a3d605 ("packet: Add GSO/csum offload support.")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@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/packet/af_packet.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 0856c125b06d..b17f9097c6fe 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1713,7 +1713,7 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) } spin_unlock(&po->bind_lock); - if (err && !refcount_read(&match->sk_ref)) { + if (err && !atomic_read(&match->sk_ref)) { list_del(&match->list); kfree(match); } @@ -2838,6 +2838,7 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) struct virtio_net_hdr vnet_hdr = { 0 }; int offset = 0; struct packet_sock *po = pkt_sk(sk); + bool has_vnet_hdr = false; int hlen, tlen, linear; int extra_len = 0; @@ -2881,6 +2882,7 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) err = packet_snd_vnet_parse(msg, &len, &vnet_hdr); if (err) goto out_unlock; + has_vnet_hdr = true; } if (unlikely(sock_flag(sk, SOCK_NOFCS))) { @@ -2941,7 +2943,7 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) packet_pick_tx_queue(dev, skb); - if (po->has_vnet_hdr) { + if (has_vnet_hdr) { err = packet_snd_vnet_gso(skb, &vnet_hdr); if (err) goto out_free; |