From: Liu Jian liujian56@huawei.com
[ Upstream commit bec217197b412d74168c6a42fc0f76d0cc9cad00 ]
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 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 Signed-off-by: Sasha Levin sashal@kernel.org --- 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 69ac686c7cae..864cd7ded2ca 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -435,8 +435,10 @@ 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)) { @@ -456,7 +458,7 @@ 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); }
@@ -478,7 +480,9 @@ 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);