linux-kernel - [PATCH 3.16 186/192] Fix regression which breaks DFS mounting

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <lsq.1507553065.139963946@decadent.org.uk>
Date:   Mon, 09 Oct 2017 13:44:25 +0100
From:   Ben Hutchings <ben@...adent.org.uk>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
CC:     akpm@...ux-foundation.org, "Aurelien Aptel" <aaptel@...e.com>,
        "Sachin Prabhu" <sprabhu@...hat.com>,
        "Steve French" <smfrench@...il.com>
Subject: [PATCH 3.16 186/192] Fix regression which breaks DFS mounting

3.16.49-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Sachin Prabhu <sprabhu@...hat.com>

commit d171356ff11ab1825e456dfb979755e01b3c54a1 upstream.

Patch a6b5058 results in -EREMOTE returned by is_path_accessible() in
cifs_mount() to be ignored which breaks DFS mounting.

Signed-off-by: Sachin Prabhu <sprabhu@...hat.com>
Reviewed-by: Aurelien Aptel <aaptel@...e.com>
Signed-off-by: Steve French <smfrench@...il.com>
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
---
 fs/cifs/connect.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -3638,14 +3638,16 @@ remote_path_check:
 			goto mount_fail_check;
 		}
 
-		rc = cifs_are_all_path_components_accessible(server,
+		if (rc != -EREMOTE) {
+			rc = cifs_are_all_path_components_accessible(server,
 							     xid, tcon, cifs_sb,
 							     full_path);
-		if (rc != 0) {
-			cifs_dbg(VFS, "cannot query dirs between root and final path, "
-				 "enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
-			cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
-			rc = 0;
+			if (rc != 0) {
+				cifs_dbg(VFS, "cannot query dirs between root and final path, "
+					 "enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
+				cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
+				rc = 0;
+			}
 		}
 		kfree(full_path);
 	}