6.6-stable review patch. If anyone has any objections, please let me know.
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From: zhangjian zhangjian496@huawei.com
commit 34331d7beed7576acfc98e991c39738b96162499 upstream.
after fabc4ed200f9, server_unresponsive add a condition to check whether client need to reconnect depending on server->lstrp. When client failed to reconnect for some time and abort connection, server->lstrp is updated for the last time. In the following scene, server->lstrp is too old. This cause next command failure in re-negotiation rather than waiting for re-negotiation done.
1. mount -t cifs -o username=Everyone,echo_internal=10 //$server_ip/export /mnt 2. ssh $server_ip "echo b > /proc/sysrq-trigger &" 3. ls /mnt 4. sleep 21s 5. ssh $server_ip "service firewalld stop" 6. ls # return EHOSTDOWN
If the interval between 5 and 6 is too small, 6 may trigger sending negotiation request. Before backgrounding cifsd thread try to receive negotiation response from server in cifs_readv_from_socket, server_unresponsive may trigger cifs_reconnect which cause 6 to be failed:
ls thread ---------------- smb2_negotiate server->tcpStatus = CifsInNegotiate compound_send_recv wait_for_compound_request
cifsd thread ---------------- cifs_readv_from_socket server_unresponsive server->tcpStatus == CifsInNegotiate && jiffies > server->lstrp + 20s cifs_reconnect cifs_abort_connection: mid_state = MID_RETRY_NEEDED
ls thread ---------------- cifs_sync_mid_result return EAGAIN smb2_negotiate return EHOSTDOWN
Though server->lstrp means last server response time, it is updated in cifs_abort_connection and cifs_get_tcp_session. We can also update server->lstrp before switching into CifsInNegotiate state to avoid failure in 6.
Fixes: 7ccc1465465d ("smb: client: fix hang in wait_for_response() for negproto") Acked-by: Paulo Alcantara (Red Hat) pc@manguebit.org Acked-by: Meetakshi Setiya msetiya@microsoft.com Signed-off-by: zhangjian zhangjian496@huawei.com Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/smb/client/connect.c | 1 + 1 file changed, 1 insertion(+)
--- a/fs/smb/client/connect.c +++ b/fs/smb/client/connect.c @@ -3982,6 +3982,7 @@ retry: return 0; }
+ server->lstrp = jiffies; server->tcpStatus = CifsInNegotiate; spin_unlock(&server->srv_lock);