cifs: fix reference leak for tlink

Don't leak a reference to tlink during the NOTIFY ioctl

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org> # v5.6+
This commit is contained in:
Ronnie Sahlberg 2020-07-09 20:39:49 +10:00 committed by Steve French
parent 8668115cf2
commit a77592a700

View File

@ -169,6 +169,7 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
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, unsigned int command, unsigned long arg)
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");