From: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
commit a77592a70081edb58a95b9da18fd5a2882a25666 upstream.
Don't leak a reference to tlink during the NOTIFY ioctl
Signed-off-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Reviewed-by: Aurelien Aptel <aaptel@xxxxxxxx>
CC: Stable <stable@xxxxxxxxxxxxxxx> # v5.6+
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/cifs/ioctl.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
--- a/fs/cifs/ioctl.c
+++ b/fs/cifs/ioctl.c
@@ -169,6 +169,7 @@ long cifs_ioctl(struct file *filep, unsi
unsigned int xid;
struct cifsFileInfo *pSMBFile = filep->private_data;
struct cifs_tcon *tcon;
+ struct tcon_link *tlink;
struct cifs_sb_info *cifs_sb;
__u64 ExtAttrBits = 0;
__u64 caps;
@@ -307,13 +308,19 @@ long cifs_ioctl(struct file *filep, unsi
break;
}
cifs_sb = CIFS_SB(inode->i_sb);
- tcon = tlink_tcon(cifs_sb_tlink(cifs_sb));
+ tlink = cifs_sb_tlink(cifs_sb);
+ if (IS_ERR(tlink)) {
+ rc = PTR_ERR(tlink);
+ break;
+ }
+ tcon = tlink_tcon(tlink);
if (tcon && tcon->ses->server->ops->notify) {
rc = tcon->ses->server->ops->notify(xid,
filep, (void __user *)arg);
cifs_dbg(FYI, "ioctl notify rc %d\n", rc);
} else
rc = -EOPNOTSUPP;
+ cifs_put_tlink(tlink);
break;
default:
cifs_dbg(FYI, "unsupported ioctl\n");
