4.11-stable review patch. If anyone has any objections, please let me know.
------------------
From: David Disseldorp <ddiss@xxxxxxx>
commit 6026685de33b0db5b2b6b0e9b41b3a1a3261033c upstream.
As with 618763958b22, an open directory may have a NULL private_data
pointer prior to readdir. CIFS_ENUMERATE_SNAPSHOTS must check for this
before dereference.
Fixes: 834170c85978 ("Enable previous version support")
Signed-off-by: David Disseldorp <ddiss@xxxxxxx>
Signed-off-by: Steve French <smfrench@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/cifs/ioctl.c | 2 ++
1 file changed, 2 insertions(+)
--- a/fs/cifs/ioctl.c
+++ b/fs/cifs/ioctl.c
@@ -213,6 +213,8 @@ long cifs_ioctl(struct file *filep, unsi
rc = smb_mnt_get_fsinfo(xid, tcon, (void __user *)arg);
break;
case CIFS_ENUMERATE_SNAPSHOTS:
+ if (pSMBFile == NULL)
+ break;
if (arg == 0) {
rc = -EINVAL;
goto cifs_ioc_exit;