cifs: cifs_chan_is_iface_active should be called with chan_lock held

commit 7257bcf3bdc785eabc4eef1f329a59815b032508 upstream.

cifs_chan_is_iface_active checks the channels of a session to see
if the associated iface is active. This should always happen
with chan_lock held. However, these two callers of this function
were missing this locking.

This change makes sure the function calls are protected with
proper locking.

Fixes: b54034a73baf ("cifs: during reconnect, update interface if necessary")
Fixes: fa1d0508bdd4 ("cifs: account for primary channel in the interface list")
Cc: stable@vger.kernel.org
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
index 76ccbdb..b82f60d 100644 (file)
--- a/fs/smb/client/connect.c
+++ b/fs/smb/client/connect.c
@@ -209,10 +209,13 @@ cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server,
        spin_lock(&cifs_tcp_ses_lock);
        list_for_each_entry_safe(ses, nses, &pserver->smb_ses_list, smb_ses_list) {
                /* check if iface is still active */
-               if (!cifs_chan_is_iface_active(ses, server))
+               spin_lock(&ses->chan_lock);
+               if (!cifs_chan_is_iface_active(ses, server)) {
+                       spin_unlock(&ses->chan_lock);
                        cifs_chan_update_iface(ses, server);
+                       spin_lock(&ses->chan_lock);
+               }
 
-               spin_lock(&ses->chan_lock);
                if (!mark_smb_session && cifs_chan_needs_reconnect(ses, server)) {
                        spin_unlock(&ses->chan_lock);
                        continue;

diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c
index e917eeb..90a881b 100644 (file)
--- a/fs/smb/client/smb2ops.c
+++ b/fs/smb/client/smb2ops.c
@@ -782,9 +782,14 @@ SMB3_request_interfaces(const unsigned int xid, struct cifs_tcon *tcon, bool in_
                goto out;
 
        /* check if iface is still active */
+       spin_lock(&ses->chan_lock);
        pserver = ses->chans[0].server;
-       if (pserver && !cifs_chan_is_iface_active(ses, pserver))
+       if (pserver && !cifs_chan_is_iface_active(ses, pserver)) {
+               spin_unlock(&ses->chan_lock);
                cifs_chan_update_iface(ses, pserver);
+               spin_lock(&ses->chan_lock);
+       }
+       spin_unlock(&ses->chan_lock);
 
 out:
        kfree(out_buf);