From 49dbe25adac42d3e06f65d1420946bec65896222 Mon Sep 17 00:00:00 2001
From: Arseniy Krasnov <avkrasnov@salutedevices.com>
Date: Tue, 10 Oct 2023 22:15:14 +0300
Subject: vsock: read from socket's error queue

This adds handling of MSG_ERRQUEUE input flag in receive call. This flag
is used to read socket's error queue instead of data queue. Possible
scenario of error queue usage is receiving completions for transmission
with MSG_ZEROCOPY flag. This patch also adds new defines: 'SOL_VSOCK'
and 'VSOCK_RECVERR'.

Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/vmw_vsock/af_vsock.c | 6 ++++++
 1 file changed, 6 insertions(+)

(limited to 'net')

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index d841f4de33b0..38486efd3d05 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -89,6 +89,7 @@
 #include <linux/types.h>
 #include <linux/bitops.h>
 #include <linux/cred.h>
+#include <linux/errqueue.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
@@ -110,6 +111,7 @@
 #include <linux/workqueue.h>
 #include <net/sock.h>
 #include <net/af_vsock.h>
+#include <uapi/linux/vm_sockets.h>
 
 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr);
 static void vsock_sk_destruct(struct sock *sk);
@@ -2137,6 +2139,10 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 	int err;
 
 	sk = sock->sk;
+
+	if (unlikely(flags & MSG_ERRQUEUE))
+		return sock_recv_errqueue(sk, msg, len, SOL_VSOCK, VSOCK_RECVERR);
+
 	vsk = vsock_sk(sk);
 	err = 0;
 
-- 
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