[PULL 070/115] chardev/char-socket: Properly make qio connections non blocking

[Paolo Bonzini]

From: Sai Pavan Boddu <sai.pavan.boddu@xilinx.com>

In tcp_chr_sync_read function, there is a possibility of socket
disconnection during blocking read, then tcp_chr_hup function would clean up
the qio channel pointers(i.e ioc, sioc).

Signed-off-by: Sai Pavan Boddu <sai.pavan.boddu@xilinx.com>
Message-Id: <1587289900-29485-1-git-send-email-sai.pavan.boddu@xilinx.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 chardev/char-socket.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/chardev/char-socket.c b/chardev/char-socket.c
index db253d4024..dd3d3ed8d6 100644
--- a/chardev/char-socket.c
+++ b/chardev/char-socket.c
@@ -550,7 +550,9 @@ static int tcp_chr_sync_read(Chardev *chr, const uint8_t 
*buf, int len)
 
     qio_channel_set_blocking(s->ioc, true, NULL);
     size = tcp_chr_recv(chr, (void *) buf, len);
-    qio_channel_set_blocking(s->ioc, false, NULL);
+    if (s->state != TCP_CHARDEV_STATE_DISCONNECTED) {
+        qio_channel_set_blocking(s->ioc, false, NULL);
+    }
     if (size == 0) {
         /* connection closed */
         tcp_chr_disconnect(chr);
-- 
2.26.2