From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:49618 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752108AbbEJU6X (ORCPT ); Sun, 10 May 2015 16:58:23 -0400 Subject: Patch "hfsplus: don't store special "osx" xattr prefix on-disk" has been added to the 4.0-stable tree To: tommyhebb@gmail.com, akpm@linux-foundation.org, anton@tuxera.com, fabf@skynet.be, gregkh@linuxfoundation.org, hch@infradead.org, htl10@users.sourceforge.net, lists@nerdbynature.de, saproj@gmail.com, slava@dubeyko.com, stable@vger.kernel.org, torvalds@linux-foundation.org, viro@zeniv.linux.org.uk Cc: , From: Date: Sun, 10 May 2015 14:32:18 +0200 Message-ID: <143126113826250@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled hfsplus: don't store special "osx" xattr prefix on-disk to the 4.0-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: hfsplus-don-t-store-special-osx-xattr-prefix-on-disk.patch and it can be found in the queue-4.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From db579e76f06e78de011b2cb7e028740a82f5558c Mon Sep 17 00:00:00 2001 From: Thomas Hebb Date: Thu, 16 Apr 2015 12:47:18 -0700 Subject: hfsplus: don't store special "osx" xattr prefix on-disk From: Thomas Hebb commit db579e76f06e78de011b2cb7e028740a82f5558c upstream. On Mac OS X, HFS+ extended attributes are not namespaced. Since we want to be compatible with OS X filesystems and yet still support the Linux namespacing system, the hfsplus driver implements a special "osx" namespace that is reported for any attribute that is not namespaced on-disk. However, the current code for getting and setting these unprefixed attributes is broken. hfsplus_osx_setattr() and hfsplus_osx_getattr() are passed names that have already had their "osx." prefixes stripped by the generic functions. The functions first, quite correctly, check those names to make sure that they aren't prefixed with a known namespace, which would allow namespace access restrictions to be bypassed. However, the functions then prepend "osx." to the name they're given before passing it on to hfsplus_getattr() and hfsplus_setattr(). Not only does this cause the "osx." prefix to be stored on-disk, defeating its purpose, it also breaks the check for the special "com.apple.FinderInfo" attribute, which is reported for all files, and as a consequence makes some userspace applications (e.g. GNU patch) fail even when extended attributes are not otherwise in use. There are five commits which have touched this particular code: 127e5f5ae51e ("hfsplus: rework functionality of getting, setting and deleting of extended attributes") b168fff72109 ("hfsplus: use xattr handlers for removexattr") bf29e886b242 ("hfsplus: correct usage of HFSPLUS_ATTR_MAX_STRLEN for non-English attributes") fcacbd95e121 ("fs/hfsplus: move xattr_name allocation in hfsplus_getxattr()") ec1bbd346f18 ("fs/hfsplus: move xattr_name allocation in hfsplus_setxattr()") The first commit creates the functions to begin with. The namespace is prepended by the original code, which I believe was correct at the time, since hfsplus_?etattr() stripped the prefix if found. The second commit removes this behavior from hfsplus_?etattr() and appears to have been intended to also remove the prefixing from hfsplus_osx_?etattr(). However, what it actually does is remove a necessary strncpy() call completely, breaking the osx namespace entirely. The third commit re-adds the strncpy() call as it was originally, but doesn't mention it in its commit message. The final two commits refactor the code and don't affect its functionality. This commit does what b168fff attempted to do (prevent the prefix from being added), but does it properly, instead of passing in an empty buffer (which is what b168fff actually did). Fixes: b168fff72109 ("hfsplus: use xattr handlers for removexattr") Signed-off-by: Thomas Hebb Cc: Hin-Tak Leung Cc: Sergei Antonov Cc: Anton Altaparmakov Cc: Fabian Frederick Cc: Christian Kujau Cc: Christoph Hellwig Cc: Al Viro Cc: Viacheslav Dubeyko Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Thomas Hebb Signed-off-by: Greg Kroah-Hartman --- fs/hfsplus/xattr.c | 42 ++++++++++++++++-------------------------- 1 file changed, 16 insertions(+), 26 deletions(-) --- a/fs/hfsplus/xattr.c +++ b/fs/hfsplus/xattr.c @@ -806,9 +806,6 @@ end_removexattr: static int hfsplus_osx_getxattr(struct dentry *dentry, const char *name, void *buffer, size_t size, int type) { - char *xattr_name; - int res; - if (!strcmp(name, "")) return -EINVAL; @@ -818,24 +815,19 @@ static int hfsplus_osx_getxattr(struct d */ if (is_known_namespace(name)) return -EOPNOTSUPP; - xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN - + XATTR_MAC_OSX_PREFIX_LEN + 1, GFP_KERNEL); - if (!xattr_name) - return -ENOMEM; - strcpy(xattr_name, XATTR_MAC_OSX_PREFIX); - strcpy(xattr_name + XATTR_MAC_OSX_PREFIX_LEN, name); - - res = hfsplus_getxattr(dentry, xattr_name, buffer, size); - kfree(xattr_name); - return res; + + /* + * osx is the namespace we use to indicate an unprefixed + * attribute on the filesystem (like the ones that OS X + * creates), so we pass the name through unmodified (after + * ensuring it doesn't conflict with another namespace). + */ + return hfsplus_getxattr(dentry, name, buffer, size); } static int hfsplus_osx_setxattr(struct dentry *dentry, const char *name, const void *buffer, size_t size, int flags, int type) { - char *xattr_name; - int res; - if (!strcmp(name, "")) return -EINVAL; @@ -845,16 +837,14 @@ static int hfsplus_osx_setxattr(struct d */ if (is_known_namespace(name)) return -EOPNOTSUPP; - xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN - + XATTR_MAC_OSX_PREFIX_LEN + 1, GFP_KERNEL); - if (!xattr_name) - return -ENOMEM; - strcpy(xattr_name, XATTR_MAC_OSX_PREFIX); - strcpy(xattr_name + XATTR_MAC_OSX_PREFIX_LEN, name); - - res = hfsplus_setxattr(dentry, xattr_name, buffer, size, flags); - kfree(xattr_name); - return res; + + /* + * osx is the namespace we use to indicate an unprefixed + * attribute on the filesystem (like the ones that OS X + * creates), so we pass the name through unmodified (after + * ensuring it doesn't conflict with another namespace). + */ + return hfsplus_setxattr(dentry, name, buffer, size, flags); } static size_t hfsplus_osx_listxattr(struct dentry *dentry, char *list, Patches currently in stable-queue which might be from tommyhebb@gmail.com are queue-4.0/hfsplus-don-t-store-special-osx-xattr-prefix-on-disk.patch