From bec217197b412d74168c6a42fc0f76d0cc9cad00 Mon Sep 17 00:00:00 2001 From: Liu Jian Date: Wed, 7 Sep 2022 15:13:11 +0800 Subject: [PATCH] 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: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: Liu Jian Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20220907071311.60534-1-liujian56@huawei.com --- net/core/skmsg.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/net/core/skmsg.c b/net/core/skmsg.c index 188f855..ca70525 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -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); -- 2.7.4