cifs: fix CIFS_ENUMERATE_SNAPSHOTS oops

As with 6187639, an open directory may have a NULL private_data pointer prior to readdir. CIFS_ENUMERATE_SNAPSHOTS must check for this before dereference. Fixes: 834170c ("Enable previous version support") Signed-off-by: David Disseldorp <[email protected]> CC: Stable <[email protected]> Signed-off-by: Steve French <[email protected]>
coreos · May 3, 2017 · 6026685 · 6026685
1 parent 0e5c795
commit 6026685
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/fs/cifs/ioctl.c b/fs/cifs/ioctl.c
@@ -213,6 +213,8 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
 			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;