sk->sk_error_queue is dequeued in four locations. All share the
exact same logic. Deduplicate.
Also collapse the two critical sections for dequeue (at the top of
the recv handler) and signal (at the bottom).
This moves signal generation for the next packet forward, which should
be harmless.
It also changes the behavior if the recv handler exits early with an
error. Previously, a signal for follow-up packets on the errqueue
would then not be scheduled. The new behavior, to always signal, is
arguably a bug fix.
For rxrpc, the change causes the same function to be called repeatedly
for each queued packet (because the recv handler == sk_error_report).
It is likely that all packets will fail for the same reason (e.g.,
memory exhaustion).
This code runs without sk_lock held, so it is not safe to trust that
sk->sk_err is immutable inbetween releasing q->lock and the subsequent
test. Introduce int err just to avoid this potential race.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
+struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
/*
* Recover an error report and clear atomically
/*
* Recover an error report and clear atomically
}
EXPORT_SYMBOL(sock_queue_err_skb);
}
EXPORT_SYMBOL(sock_queue_err_skb);
+struct sk_buff *sock_dequeue_err_skb(struct sock *sk)
+{
+ struct sk_buff_head *q = &sk->sk_error_queue;
+ struct sk_buff *skb, *skb_next;
+ int err = 0;
+
+ spin_lock_bh(&q->lock);
+ skb = __skb_dequeue(q);
+ if (skb && (skb_next = skb_peek(q)))
+ err = SKB_EXT_ERR(skb_next)->ee.ee_errno;
+ spin_unlock_bh(&q->lock);
+
+ sk->sk_err = err;
+ if (err)
+ sk->sk_error_report(sk);
+
+ return skb;
+}
+EXPORT_SYMBOL(sock_dequeue_err_skb);
+
void __skb_tstamp_tx(struct sk_buff *orig_skb,
struct skb_shared_hwtstamps *hwtstamps,
struct sock *sk, int tstype)
void __skb_tstamp_tx(struct sk_buff *orig_skb,
struct skb_shared_hwtstamps *hwtstamps,
struct sock *sk, int tstype)
int level, int type)
{
struct sock_exterr_skb *serr;
int level, int type)
{
struct sock_exterr_skb *serr;
- struct sk_buff *skb, *skb2;
int copied, err;
err = -EAGAIN;
int copied, err;
err = -EAGAIN;
- skb = skb_dequeue(&sk->sk_error_queue);
+ skb = sock_dequeue_err_skb(sk);
if (skb == NULL)
goto out;
if (skb == NULL)
goto out;
msg->msg_flags |= MSG_ERRQUEUE;
err = copied;
msg->msg_flags |= MSG_ERRQUEUE;
err = copied;
- /* Reset and regenerate socket error */
- spin_lock_bh(&sk->sk_error_queue.lock);
- sk->sk_err = 0;
- if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
- sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
- spin_unlock_bh(&sk->sk_error_queue.lock);
- sk->sk_error_report(sk);
- } else
- spin_unlock_bh(&sk->sk_error_queue.lock);
-
out_free_skb:
kfree_skb(skb);
out:
out_free_skb:
kfree_skb(skb);
out:
int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
{
struct sock_exterr_skb *serr;
int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
{
struct sock_exterr_skb *serr;
- struct sk_buff *skb, *skb2;
DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
struct {
struct sock_extended_err ee;
DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
struct {
struct sock_extended_err ee;
int copied;
err = -EAGAIN;
int copied;
err = -EAGAIN;
- skb = skb_dequeue(&sk->sk_error_queue);
+ skb = sock_dequeue_err_skb(sk);
if (skb == NULL)
goto out;
if (skb == NULL)
goto out;
msg->msg_flags |= MSG_ERRQUEUE;
err = copied;
msg->msg_flags |= MSG_ERRQUEUE;
err = copied;
- /* Reset and regenerate socket error */
- spin_lock_bh(&sk->sk_error_queue.lock);
- sk->sk_err = 0;
- skb2 = skb_peek(&sk->sk_error_queue);
- if (skb2 != NULL) {
- sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
- spin_unlock_bh(&sk->sk_error_queue.lock);
- sk->sk_error_report(sk);
- } else
- spin_unlock_bh(&sk->sk_error_queue.lock);
-
out_free_skb:
kfree_skb(skb);
out:
out_free_skb:
kfree_skb(skb);
out:
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct sock_exterr_skb *serr;
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct sock_exterr_skb *serr;
- struct sk_buff *skb, *skb2;
DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
struct {
struct sock_extended_err ee;
DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
struct {
struct sock_extended_err ee;
int copied;
err = -EAGAIN;
int copied;
err = -EAGAIN;
- skb = skb_dequeue(&sk->sk_error_queue);
+ skb = sock_dequeue_err_skb(sk);
if (skb == NULL)
goto out;
if (skb == NULL)
goto out;
msg->msg_flags |= MSG_ERRQUEUE;
err = copied;
msg->msg_flags |= MSG_ERRQUEUE;
err = copied;
- /* Reset and regenerate socket error */
- spin_lock_bh(&sk->sk_error_queue.lock);
- sk->sk_err = 0;
- if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
- sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
- spin_unlock_bh(&sk->sk_error_queue.lock);
- sk->sk_error_report(sk);
- } else {
- spin_unlock_bh(&sk->sk_error_queue.lock);
- }
-
out_free_skb:
kfree_skb(skb);
out:
out_free_skb:
kfree_skb(skb);
out:
_enter("%p{%d}", sk, local->debug_id);
_enter("%p{%d}", sk, local->debug_id);
- skb = skb_dequeue(&sk->sk_error_queue);
+ skb = sock_dequeue_err_skb(sk);
if (!skb) {
_leave("UDP socket errqueue empty");
return;
if (!skb) {
_leave("UDP socket errqueue empty");
return;
skb_queue_tail(&trans->error_queue, skb);
rxrpc_queue_work(&trans->error_handler);
skb_queue_tail(&trans->error_queue, skb);
rxrpc_queue_work(&trans->error_handler);
- /* reset and regenerate socket error */
- spin_lock_bh(&sk->sk_error_queue.lock);
- sk->sk_err = 0;
- skb = skb_peek(&sk->sk_error_queue);
- if (skb) {
- sk->sk_err = SKB_EXT_ERR(skb)->ee.ee_errno;
- spin_unlock_bh(&sk->sk_error_queue.lock);
- sk->sk_error_report(sk);
- } else {
- spin_unlock_bh(&sk->sk_error_queue.lock);
- }
-