From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:43004 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932582AbdJJTwj (ORCPT ); Tue, 10 Oct 2017 15:52:39 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Theodore Tso , Jan Kara , Andreas Gruenbacher Subject: [PATCH 3.18 31/32] ext4: Dont clear SGID when inheriting ACLs Date: Tue, 10 Oct 2017 21:50:52 +0200 Message-Id: <20171010184828.230016604@linuxfoundation.org> In-Reply-To: <20171010184827.005589196@linuxfoundation.org> References: <20171010184827.005589196@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jan Kara commit a3bb2d5587521eea6dab2d05326abb0afb460abd upstream. When new directory 'DIR1' is created in a directory 'DIR0' with SGID bit set, DIR1 is expected to have SGID bit set (and owning group equal to the owning group of 'DIR0'). However when 'DIR0' also has some default ACLs that 'DIR1' inherits, setting these ACLs will result in SGID bit on 'DIR1' to get cleared if user is not member of the owning group. Fix the problem by moving posix_acl_update_mode() out of __ext4_set_acl() into ext4_set_acl(). That way the function will not be called when inheriting ACLs which is what we want as it prevents SGID bit clearing and the mode has been properly set by posix_acl_create() anyway. Fixes: 073931017b49d9458aa351605b43a7e34598caef Signed-off-by: Theodore Ts'o Signed-off-by: Jan Kara Reviewed-by: Andreas Gruenbacher Signed-off-by: Greg Kroah-Hartman --- fs/ext4/acl.c | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) --- a/fs/ext4/acl.c +++ b/fs/ext4/acl.c @@ -200,13 +200,6 @@ __ext4_set_acl(handle_t *handle, struct switch (type) { case ACL_TYPE_ACCESS: name_index = EXT4_XATTR_INDEX_POSIX_ACL_ACCESS; - if (acl) { - error = posix_acl_update_mode(inode, &inode->i_mode, &acl); - if (error) - return error; - inode->i_ctime = ext4_current_time(inode); - ext4_mark_inode_dirty(handle, inode); - } break; case ACL_TYPE_DEFAULT: @@ -239,6 +232,8 @@ ext4_set_acl(struct inode *inode, struct { handle_t *handle; int error, retries = 0; + umode_t mode = inode->i_mode; + int update_mode = 0; retry: handle = ext4_journal_start(inode, EXT4_HT_XATTR, @@ -246,7 +241,20 @@ retry: if (IS_ERR(handle)) return PTR_ERR(handle); + if ((type == ACL_TYPE_ACCESS) && acl) { + error = posix_acl_update_mode(inode, &mode, &acl); + if (error) + goto out_stop; + update_mode = 1; + } + error = __ext4_set_acl(handle, inode, type, acl); + if (!error && update_mode) { + inode->i_mode = mode; + inode->i_ctime = ext4_current_time(inode); + ext4_mark_inode_dirty(handle, inode); + } +out_stop: ext4_journal_stop(handle); if (error == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) goto retry;