cifs: fix session state check in smb2_find_smb_ses

Chech the session state and skip it if it's exiting.

Signed-off-by: Winston Wen <wentao@uniontech.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/smb/client/smb2transport.c

@@ -153,7 +153,14 @@ smb2_find_smb_ses_unlocked(struct TCP_Server_Info *server, __u64 ses_id)
 	list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
 		if (ses->Suid != ses_id)
 			continue;
+
+		spin_lock(&ses->ses_lock);
+		if (ses->ses_status == SES_EXITING) {
+			spin_unlock(&ses->ses_lock);
+			continue;
+		}
 		++ses->ses_count;
+		spin_unlock(&ses->ses_lock);
 		return ses;
 	}