diff options
| author | Eric Dumazet <edumazet@google.com> | 2015-07-17 10:19:23 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-07-21 00:02:44 -0700 |
| commit | b8a23e8d8e31abeda2f6cfa36a772414b2a86ffc (patch) | |
| tree | ef089a2324ced0fd03bff823419458d6aa2a2ee4 /net/caif/caif_socket.c | |
| parent | e3426ca7bc2957ee072f61360c2b81b4adb629ad (diff) | |
| download | lwn-b8a23e8d8e31abeda2f6cfa36a772414b2a86ffc.tar.gz lwn-b8a23e8d8e31abeda2f6cfa36a772414b2a86ffc.zip | |
caif: fix leaks and race in caif_queue_rcv_skb()
1) If sk_filter() is applied, skb was leaked (not freed)
2) Testing SOCK_DEAD twice is racy :
packet could be freed while already queued.
3) Remove obsolete comment about caching skb->len
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/caif/caif_socket.c')
| -rw-r--r-- | net/caif/caif_socket.c | 19 |
1 files changed, 8 insertions, 11 deletions
diff --git a/net/caif/caif_socket.c b/net/caif/caif_socket.c index 3cc71b9f5517..cc858919108e 100644 --- a/net/caif/caif_socket.c +++ b/net/caif/caif_socket.c @@ -121,12 +121,13 @@ static void caif_flow_ctrl(struct sock *sk, int mode) * Copied from sock.c:sock_queue_rcv_skb(), but changed so packets are * not dropped, but CAIF is sending flow off instead. */ -static int caif_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) +static void caif_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) { int err; unsigned long flags; struct sk_buff_head *list = &sk->sk_receive_queue; struct caifsock *cf_sk = container_of(sk, struct caifsock, sk); + bool queued = false; if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >= (unsigned int)sk->sk_rcvbuf && rx_flow_is_on(cf_sk)) { @@ -139,7 +140,8 @@ static int caif_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) err = sk_filter(sk, skb); if (err) - return err; + goto out; + if (!sk_rmem_schedule(sk, skb, skb->truesize) && rx_flow_is_on(cf_sk)) { set_rx_flow_off(cf_sk); net_dbg_ratelimited("sending flow OFF due to rmem_schedule\n"); @@ -147,21 +149,16 @@ static int caif_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) } skb->dev = NULL; skb_set_owner_r(skb, sk); - /* Cache the SKB length before we tack it onto the receive - * queue. Once it is added it no longer belongs to us and - * may be freed by other threads of control pulling packets - * from the queue. - */ spin_lock_irqsave(&list->lock, flags); - if (!sock_flag(sk, SOCK_DEAD)) + queued = !sock_flag(sk, SOCK_DEAD); + if (queued) __skb_queue_tail(list, skb); spin_unlock_irqrestore(&list->lock, flags); - - if (!sock_flag(sk, SOCK_DEAD)) +out: + if (queued) sk->sk_data_ready(sk); else kfree_skb(skb); - return 0; } /* Packet Receive Callback function called from CAIF Stack */ |