From dfbafc995304ebb9a9b03f65083e6e9cea143b20 Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca <sd@queasysnail.net> Date: Fri, 24 Jul 2015 18:19:25 +0200 Subject: tcp: fix recv with flags MSG_WAITALL | MSG_PEEK Currently, tcp_recvmsg enters a busy loop in sk_wait_data if called with flags = MSG_WAITALL | MSG_PEEK. sk_wait_data waits for sk_receive_queue not empty, but in this case, the receive queue is not empty, but does not contain any skb that we can use. Add a "last skb seen on receive queue" argument to sk_wait_data, so that it sleeps until the receive queue has new skbs. Link: https://bugzilla.kernel.org/show_bug.cgi?id=99461 Link: https://sourceware.org/bugzilla/show_bug.cgi?id=18493 Link: https://bugzilla.redhat.com/show_bug.cgi?id=1205258 Reported-by: Enrico Scholz <rh-bugzilla@ensc.de> Reported-by: Dan Searle <dan@censornet.com> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- net/core/sock.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'net/core/sock.c') diff --git a/net/core/sock.c b/net/core/sock.c index 08f16db46070..8a14f1285fc4 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1967,20 +1967,21 @@ static void __release_sock(struct sock *sk) * sk_wait_data - wait for data to arrive at sk_receive_queue * @sk: sock to wait on * @timeo: for how long + * @skb: last skb seen on sk_receive_queue * * Now socket state including sk->sk_err is changed only under lock, * hence we may omit checks after joining wait queue. * We check receive queue before schedule() only as optimization; * it is very likely that release_sock() added new data. */ -int sk_wait_data(struct sock *sk, long *timeo) +int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb) { int rc; DEFINE_WAIT(wait); prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); - rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); + rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb); clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); finish_wait(sk_sleep(sk), &wait); return rc; -- cgit v1.2.3-70-g09d2 From 8a68173691f036613e3d4e6bf8dc129d4a7bf383 Mon Sep 17 00:00:00 2001 From: Sowmini Varadhan <sowmini.varadhan@oracle.com> Date: Thu, 30 Jul 2015 15:50:36 +0200 Subject: net: sk_clone_lock() should only do get_net() if the parent is not a kernel socket The newsk returned by sk_clone_lock should hold a get_net() reference if, and only if, the parent is not a kernel socket (making this similar to sk_alloc()). E.g,. for the SYN_RECV path, tcp_v4_syn_recv_sock->..inet_csk_clone_lock sets up the syn_recv newsk from sk_clone_lock. When the parent (listen) socket is a kernel socket (defined in sk_alloc() as having sk_net_refcnt == 0), then the newsk should also have a 0 sk_net_refcnt and should not hold a get_net() reference. Fixes: 26abe14379f8 ("net: Modify sk_alloc to not reference count the netns of kernel sockets.") Acked-by: Eric Dumazet <edumazet@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- net/core/sock.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/core/sock.c') diff --git a/net/core/sock.c b/net/core/sock.c index 8a14f1285fc4..193901d09757 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1497,7 +1497,8 @@ struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) sock_copy(newsk, sk); /* SANITY */ - get_net(sock_net(newsk)); + if (likely(newsk->sk_net_refcnt)) + get_net(sock_net(newsk)); sk_node_init(&newsk->sk_node); sock_lock_init(newsk); bh_lock_sock(newsk); -- cgit v1.2.3-70-g09d2 From 69dba9bbc50609f19ee89d62d5199c81fcbc74b2 Mon Sep 17 00:00:00 2001 From: Jean Sacren <sakiwit@gmail.com> Date: Thu, 27 Aug 2015 18:05:49 -0600 Subject: sock: fix kernel doc error The symbol '__sk_reclaim' is not present in the current tree. Apparently '__sk_reclaim' was meant to be '__sk_mem_reclaim', so fix it with the right symbol name for the kernel doc. Signed-off-by: Jean Sacren <sakiwit@gmail.com> Cc: Hideo Aoki <haoki@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- net/core/sock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/core/sock.c') diff --git a/net/core/sock.c b/net/core/sock.c index 193901d09757..ca2984afe16e 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2078,7 +2078,7 @@ suppress_allocation: EXPORT_SYMBOL(__sk_mem_schedule); /** - * __sk_reclaim - reclaim memory_allocated + * __sk_mem_reclaim - reclaim memory_allocated * @sk: socket * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple) */ -- cgit v1.2.3-70-g09d2