From: Paulo Alcantara <pc@xxxxxxxxxxxxx>
[ Upstream commit 7ccc1465465d78e6411b7bd730d06e7435802b5c ]
Call cifs_reconnect() to wake up processes waiting on negotiate
protocol to handle the case where server abruptly shut down and had no
chance to properly close the socket.
Simple reproducer:
ssh 192.168.2.100 pkill -STOP smbd
mount.cifs //192.168.2.100/test /mnt -o ... [never returns]
Cc: Rickard Andersson <rickaran@xxxxxxxx>
Signed-off-by: Paulo Alcantara (Red Hat) <pc@xxxxxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/smb/client/connect.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
index d2307162a2de..e325e06357ff 100644
--- a/fs/smb/client/connect.c
+++ b/fs/smb/client/connect.c
@@ -656,6 +656,19 @@ allocate_buffers(struct TCP_Server_Info *server)
static bool
server_unresponsive(struct TCP_Server_Info *server)
{
+ /*
+ * If we're in the process of mounting a share or reconnecting a session
+ * and the server abruptly shut down (e.g. socket wasn't closed, packet
+ * had been ACK'ed but no SMB response), don't wait longer than 20s to
+ * negotiate protocol.
+ */
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus == CifsInNegotiate &&
+ time_after(jiffies, server->lstrp + 20 * HZ)) {
+ spin_unlock(&server->srv_lock);
+ cifs_reconnect(server, false);
+ return true;
+ }
/*
* We need to wait 3 echo intervals to make sure we handle such
* situations right:
@@ -667,7 +680,6 @@ server_unresponsive(struct TCP_Server_Info *server)
* 65s kernel_recvmsg times out, and we see that we haven't gotten
* a response in >60s.
*/
- spin_lock(&server->srv_lock);
if ((server->tcpStatus == CifsGood ||
server->tcpStatus == CifsNeedNegotiate) &&
(!server->ops->can_echo || server->ops->can_echo(server)) &&
--
2.43.0
