From 1dfd18d0571231d030f325bfcd80f5c42a56a53e Mon Sep 17 00:00:00 2001
From: Sachin Prabhu <sprabhu@redhat.com>
Date: Tue, 16 Jun 2015 16:36:17 +0100
Subject: [PATCH] cifs: Unset CIFS_MOUNT_POSIX_PATHS flag when following dfs
 mounts
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In a dfs setup where the client transitions from a server which supports
posix paths to a server which doesn't support posix paths, the flag
CIFS_MOUNT_POSIX_PATHS is not reset. This leads to the wrong directory
separator being used causing smb commands to fail.

Consider the following case where a dfs share on a samba server points
to a share on windows smb server.
 # mount -t cifs -o .. //vm140-31/dfsroot/testwin/
 # ls -l /mnt; touch /mnt/a
 total 0
 touch: cannot touch ‘/mnt/a’: No such file or directory

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Acked-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Steve French <steve.french@primarydata.com>
---
 fs/cifs/connect.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 247f4dd228cc..773f4dc77630 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -3472,6 +3472,8 @@ try_mount_again:
 		else if (ses)
 			cifs_put_smb_ses(ses);
 
+		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_POSIX_PATHS;
+
 		free_xid(xid);
 	}
 #endif