[PATCH 5.9 25/75] cifs: add NULL check for ses->tcon_ipc

From: Greg Kroah-Hartman
Date: Thu Dec 10 2020 - 09:45:21 EST


From: Aurelien Aptel <aaptel@xxxxxxxx>

commit 59463eb88829f646aed13283fd84d02a475334fe upstream.

In some scenarios (DFS and BAD_NETWORK_NAME) set_root_set() can be
called with a NULL ses->tcon_ipc.

Signed-off-by: Aurelien Aptel <aaptel@xxxxxxxx>
Reviewed-by: Paulo Alcantara (SUSE) <pc@xxxxxx>
CC: Stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/cifs/connect.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -4768,7 +4768,8 @@ static void set_root_ses(struct cifs_sb_
if (ses) {
spin_lock(&cifs_tcp_ses_lock);
ses->ses_count++;
- ses->tcon_ipc->remap = cifs_remap(cifs_sb);
+ if (ses->tcon_ipc)
+ ses->tcon_ipc->remap = cifs_remap(cifs_sb);
spin_unlock(&cifs_tcp_ses_lock);
}
*root_ses = ses;