skmsg: Schedule psock work if the cached skb exists on the psock

In sk_psock_backlog function, for ingress direction skb, if no new data
packet arrives after the skb is cached, the cached skb does not have a
chance to be added to the receive queue of psock. As a result, the cached
skb cannot be received by the upper-layer application. Fix this by reschedule
the psock work to dispose the cached skb in sk_msg_recvmsg function.

Fixes: 604326b41a ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220907071311.60534-1-liujian56@huawei.com
This commit is contained in:
Liu Jian 2022-09-07 15:13:11 +08:00 committed by Daniel Borkmann
parent 043a7356db
commit bec217197b

View File

@ -434,8 +434,10 @@ int sk_msg_recvmsg(struct sock *sk, struct sk_psock *psock, struct msghdr *msg,
if (copied + copy > len)
copy = len - copied;
copy = copy_page_to_iter(page, sge->offset, copy, iter);
if (!copy)
return copied ? copied : -EFAULT;
if (!copy) {
copied = copied ? copied : -EFAULT;
goto out;
}
copied += copy;
if (likely(!peek)) {
@ -455,7 +457,7 @@ int sk_msg_recvmsg(struct sock *sk, struct sk_psock *psock, struct msghdr *msg,
* didn't copy the entire length lets just break.
*/
if (copy != sge->length)
return copied;
goto out;
sk_msg_iter_var_next(i);
}
@ -477,7 +479,9 @@ int sk_msg_recvmsg(struct sock *sk, struct sk_psock *psock, struct msghdr *msg,
}
msg_rx = sk_psock_peek_msg(psock);
}
out:
if (psock->work_state.skb && copied > 0)
schedule_work(&psock->work);
return copied;
}
EXPORT_SYMBOL_GPL(sk_msg_recvmsg);