From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934030AbdA0LTh (ORCPT ); Fri, 27 Jan 2017 06:19:37 -0500 Received: from mx2.suse.de ([195.135.220.15]:35817 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933915AbdA0LNT (ORCPT ); Fri, 27 Jan 2017 06:13:19 -0500 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Sachin Prabhu , Steve French , Jiri Slaby Subject: [PATCH 3.12 199/235] Compare prepaths when comparing superblocks Date: Fri, 27 Jan 2017 11:55:32 +0100 Message-Id: X-Mailer: git-send-email 2.11.0 In-Reply-To: <5b46dc789ca2be4046e4e40a131858d386cac741.1485514374.git.jslaby@suse.cz> References: <5b46dc789ca2be4046e4e40a131858d386cac741.1485514374.git.jslaby@suse.cz> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sachin Prabhu 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit c1d8b24d18192764fe82067ec6aa8d4c3bf094e0 upstream. The patch Fs/cifs: make share unaccessible at root level mountable makes use of prepaths when any component of the underlying path is inaccessible. When mounting 2 separate shares having different prepaths but are other wise similar in other respects, we end up sharing superblocks when we shouldn't be doing so. Signed-off-by: Sachin Prabhu Tested-by: Aurelien Aptel Signed-off-by: Steve French Acked-by: Aurelien Aptel Signed-off-by: Jiri Slaby --- fs/cifs/connect.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 98c9c867f1b3..7491e8445458 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -2742,6 +2742,24 @@ compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data) return 1; } +static int +match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data) +{ + struct cifs_sb_info *old = CIFS_SB(sb); + struct cifs_sb_info *new = mnt_data->cifs_sb; + + if (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) { + if (!(new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH)) + return 0; + /* The prepath should be null terminated strings */ + if (strcmp(new->prepath, old->prepath)) + return 0; + + return 1; + } + return 0; +} + int cifs_match_super(struct super_block *sb, void *data) { @@ -2769,7 +2787,8 @@ cifs_match_super(struct super_block *sb, void *data) if (!match_server(tcp_srv, volume_info) || !match_session(ses, volume_info) || - !match_tcon(tcon, volume_info->UNC)) { + !match_tcon(tcon, volume_info->UNC) || + !match_prepath(sb, mnt_data)) { rc = 0; goto out; } -- 2.11.0