linux-stable.git/fs/hfsplus, branch linux-3.12.y

posix_acl: Clear SGID bit when setting file permissions

2017-01-27T10:15:59+00:00

commit 073931017b49d9458aa351605b43a7e34598caef upstream.

When file permissions are modified via chmod(2) and the user is not in
the owning group or capable of CAP_FSETID, the setgid bit is cleared in
inode_change_ok().  Setting a POSIX ACL via setxattr(2) sets the file
permissions as well as the new ACL, but doesn't clear the setgid bit in
a similar way; this allows to bypass the check in chmod(2).  Fix that.

Reviewed-by: Christoph Hellwig 
Reviewed-by: Jeff Layton 
Signed-off-by: Jan Kara 
Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Jiri Slaby

hfs,hfsplus: cache pages correctly between bnode_create and bnode_free

2015-09-30T11:47:37+00:00

commit 7cb74be6fd827e314f81df3c5889b87e4c87c569 upstream.

Pages looked up by __hfs_bnode_create() (called by hfs_bnode_create() and
hfs_bnode_find() for finding or creating pages corresponding to an inode)
are immediately kmap()'ed and used (both read and write) and kunmap()'ed,
and should not be page_cache_release()'ed until hfs_bnode_free().

This patch fixes a problem I first saw in July 2012: merely running "du"
on a large hfsplus-mounted directory a few times on a reasonably loaded
system would get the hfsplus driver all confused and complaining about
B-tree inconsistencies, and generates a "BUG: Bad page state".  Most
recently, I can generate this problem on up-to-date Fedora 22 with shipped
kernel 4.0.5, by running "du /" (="/" + "/home" + "/mnt" + other smaller
mounts) and "du /mnt" simultaneously on two windows, where /mnt is a
lightly-used QEMU VM image of the full Mac OS X 10.9:

$ df -i / /home /mnt
Filesystem                  Inodes   IUsed      IFree IUse% Mounted on
/dev/mapper/fedora-root    3276800  551665    2725135   17% /
/dev/mapper/fedora-home   52879360  716221   52163139    2% /home
/dev/nbd0p2             4294967295 1387818 4293579477    1% /mnt

After applying the patch, I was able to run "du /" (60+ times) and "du
/mnt" (150+ times) continuously and simultaneously for 6+ hours.

There are many reports of the hfsplus driver getting confused under load
and generating "BUG: Bad page state" or other similar issues over the
years.  [1]

The unpatched code [2] has always been wrong since it entered the kernel
tree.  The only reason why it gets away with it is that the
kmap/memcpy/kunmap follow very quickly after the page_cache_release() so
the kernel has not had a chance to reuse the memory for something else,
most of the time.

The current RW driver appears to have followed the design and development
of the earlier read-only hfsplus driver [3], where-by version 0.1 (Dec
2001) had a B-tree node-centric approach to
read_cache_page()/page_cache_release() per bnode_get()/bnode_put(),
migrating towards version 0.2 (June 2002) of caching and releasing pages
per inode extents.  When the current RW code first entered the kernel [2]
in 2005, there was an REF_PAGES conditional (and "//" commented out code)
to switch between B-node centric paging to inode-centric paging.  There
was a mistake with the direction of one of the REF_PAGES conditionals in
__hfs_bnode_create().  In a subsequent "remove debug code" commit [4], the
read_cache_page()/page_cache_release() per bnode_get()/bnode_put() were
removed, but a page_cache_release() was mistakenly left in (propagating
the "REF_PAGES <-> !REF_PAGE" mistake), and the commented-out
page_cache_release() in bnode_release() (which should be spanned by
!REF_PAGES) was never enabled.

References:
[1]:
Michael Fox, Apr 2013
http://www.spinics.net/lists/linux-fsdevel/msg63807.html
("hfsplus volume suddenly inaccessable after 'hfs: recoff %d too large'")

Sasha Levin, Feb 2015
http://lkml.org/lkml/2015/2/20/85 ("use after free")

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/740814
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1027887
https://bugzilla.kernel.org/show_bug.cgi?id=42342
https://bugzilla.kernel.org/show_bug.cgi?id=63841
https://bugzilla.kernel.org/show_bug.cgi?id=78761

[2]:
http://git.kernel.org/cgit/linux/kernel/git/tglx/history.git/commit/\
fs/hfs/bnode.c?id=d1081202f1d0ee35ab0beb490da4b65d4bc763db
commit d1081202f1d0ee35ab0beb490da4b65d4bc763db
Author: Andrew Morton 
Date:   Wed Feb 25 16:17:36 2004 -0800

    [PATCH] HFS rewrite

http://git.kernel.org/cgit/linux/kernel/git/tglx/history.git/commit/\
fs/hfsplus/bnode.c?id=91556682e0bf004d98a529bf829d339abb98bbbd

commit 91556682e0bf004d98a529bf829d339abb98bbbd
Author: Andrew Morton 
Date:   Wed Feb 25 16:17:48 2004 -0800

    [PATCH] HFS+ support

[3]:
http://sourceforge.net/projects/linux-hfsplus/

http://sourceforge.net/projects/linux-hfsplus/files/Linux%202.4.x%20patch/hfsplus%200.1/
http://sourceforge.net/projects/linux-hfsplus/files/Linux%202.4.x%20patch/hfsplus%200.2/

http://linux-hfsplus.cvs.sourceforge.net/viewvc/linux-hfsplus/linux/\
fs/hfsplus/bnode.c?r1=1.4&r2=1.5

Date:   Thu Jun 6 09:45:14 2002 +0000
Use buffer cache instead of page cache in bnode.c. Cache inode extents.

[4]:
http://git.kernel.org/cgit/linux/kernel/git/\
stable/linux-stable.git/commit/?id=a5e3985fa014029eb6795664c704953720cc7f7d

commit a5e3985fa014029eb6795664c704953720cc7f7d
Author: Roman Zippel 
Date:   Tue Sep 6 15:18:47 2005 -0700

[PATCH] hfs: remove debug code

Signed-off-by: Hin-Tak Leung 
Signed-off-by: Sergei Antonov 
Reviewed-by: Anton Altaparmakov 
Reported-by: Sasha Levin 
Cc: Al Viro 
Cc: Christoph Hellwig 
Cc: Vyacheslav Dubeyko 
Cc: Sougata Santra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Jiri Slaby

hfsplus: fix B-tree corruption after insertion at position 0

2015-04-09T12:14:12+00:00

commit 98cf21c61a7f5419d82f847c4d77bf6e96a76f5f upstream.

Fix B-tree corruption when a new record is inserted at position 0 in the
node in hfs_brec_insert().  In this case a hfs_brec_update_parent() is
called to update the parent index node (if exists) and it is passed
hfs_find_data with a search_key containing a newly inserted key instead
of the key to be updated.  This results in an inconsistent index node.
The bug reproduces on my machine after an extents overflow record for
the catalog file (CNID=4) is inserted into the extents overflow B-tree.
Because of a low (reserved) value of CNID=4, it has to become the first
record in the first leaf node.

The resulting first leaf node is correct:

  ----------------------------------------------------
  | key0.CNID=4 | key1.CNID=123 | key2.CNID=456, ... |
  ----------------------------------------------------

But the parent index key0 still contains the previous key CNID=123:

  -----------------------
  | key0.CNID=123 | ... |
  -----------------------

A change in hfs_brec_insert() makes hfs_brec_update_parent() work
correctly by preventing it from getting fd->record=-1 value from
__hfs_brec_find().

Along the way, I removed duplicate code with unification of the if
condition.  The resulting code is equivalent to the original code
because node is never 0.

Also hfs_brec_update_parent() will now return an error after getting a
negative fd->record value.  However, the return value of
hfs_brec_update_parent() is not checked anywhere in the file and I'm
leaving it unchanged by this patch.  brec.c lacks error checking after
some other calls too, but this issue is of less importance than the one
being fixed by this patch.

Signed-off-by: Sergei Antonov 
Cc: Joe Perches 
Reviewed-by: Vyacheslav Dubeyko 
Acked-by: Hin-Tak Leung 
Cc: Anton Altaparmakov 
Cc: Al Viro 
Cc: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Jiri Slaby

hfsplus: emit proper file type from readdir

2014-11-19T22:44:32+00:00

commit 97a62eaefdc196969e9d3857f65fc8a90ee1fe3c upstream.

hfsplus_readdir() incorrectly returned DT_REG for symbolic links and
special files.  Return DT_REG, DT_LNK, DT_FIFO, DT_CHR, DT_BLK, DT_SOCK,
or DT_UNKNOWN according to mode field in catalog record.  Programs
relying on information from readdir will now work correctly with HFS+.

Signed-off-by: Sergei Antonov 
Cc: Anton Altaparmakov 
Cc: Al Viro 
Cc: Christoph Hellwig 
Cc: Vyacheslav Dubeyko 
Cc: Hin-Tak Leung 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Jiri Slaby

fs/hfsplus/extents.c: fix concurrent acess of alloc_blocks

2014-11-19T22:44:32+00:00

commit d7bdb996aef67ea24c62707ca4e29b07025e9683 upstream.

Concurrent access to alloc_blocks in hfsplus_inode_info() is protected
by extents_lock mutex.  This patch fixes two instances where
alloc_blocks modification was not protected with this lock.

This fixes possible allocation bitmap corruption in race conditions
while extending and truncating files.

[akpm@linux-foundation.org: take extents_lock before taking a copy of ->alloc_blocks]
[akpm@linux-foundation.org: remove now-unused label `out']
Signed-off-by: Sougata Santra 
Reviewed-by: Christoph Hellwig 
Cc: Vyacheslav Dubeyko 
Cc: Alexey Khoroshilov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 

Signed-off-by: Jiri Slaby

hfsplus: fix remount issue

2014-11-19T22:44:32+00:00

commit bd2c00353286d63542a8a0896a8c747f7c880edd upstream.

Current implementation of HFS+ driver has small issue with remount
option.  Namely, for example, you are unable to remount from RO mode
into RW mode by means of command "mount -o remount,rw /dev/loop0
/mnt/hfsplus".  Trying to execute sequence of commands results in an
error message:

  mount /dev/loop0 /mnt/hfsplus
  mount -o remount,ro /dev/loop0 /mnt/hfsplus
  mount -o remount,rw /dev/loop0 /mnt/hfsplus

  mount: you must specify the filesystem type

  mount -t hfsplus -o remount,rw /dev/loop0 /mnt/hfsplus

  mount: /mnt/hfsplus not mounted or bad option

The reason of such issue is failure of mount syscall:

  mount("/dev/loop0", "/mnt/hfsplus", 0x2282a60, MS_MGC_VAL|MS_REMOUNT, NULL) = -1 EINVAL (Invalid argument)

Namely, hfsplus_parse_options_remount() method receives empty "input"
argument and return false in such case.  As a result, hfsplus_remount()
returns -EINVAL error code.

This patch fixes the issue by means of return true for the case of empty
"input" argument in hfsplus_parse_options_remount() method.

Signed-off-by: Vyacheslav Dubeyko 
Cc: Al Viro 
Cc: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Jiri Slaby

truncate: drop 'oldsize' truncate_pagecache() parameter

2013-09-12T22:38:02+00:00

truncate_pagecache() doesn't care about old size since commit
cedabed49b39 ("vfs: Fix vmtruncate() regression").  Let's drop it.

Signed-off-by: Kirill A. Shutemov 
Cc: OGAWA Hirofumi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

hfsplus: integrate POSIX ACLs support into driver

2013-09-11T22:59:01+00:00

Integrate implemented POSIX ACLs support into hfsplus driver.

Signed-off-by: Vyacheslav Dubeyko 
Cc: Al Viro 
Cc: Christoph Hellwig 
Cc: Hin-Tak Leung 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

hfsplus: implement POSIX ACLs support

2013-09-11T22:59:01+00:00

Implement POSIX ACLs support in hfsplus driver.

Signed-off-by: Vyacheslav Dubeyko 
Cc: Al Viro 
Cc: Christoph Hellwig 
Cc: Hin-Tak Leung 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

hfsplus: add necessary declarations for POSIX ACLs support

2013-09-11T22:59:00+00:00

This patchset implements POSIX ACLs support in hfsplus driver.

Mac OS X beginning with version 10.4 ("Tiger") support NFSv4 ACLs, which
are part of the NFSv4 standard.  HFS+ stores ACLs in the form of
specially named extended attributes (com.apple.system.Security).

But this patchset doesn't use "com.apple.system.Security" extended
attributes.  It implements support of POSIX ACLs in the form of extended
attributes with names "system.posix_acl_access" and
"system.posix_acl_default".  These xattrs are treated only under Linux.
POSIX ACLs doesn't mean something under Mac OS X.  Thereby, this patch
set provides opportunity to use POSIX ACLs under Linux on HFS+
filesystem.

This patch:

Add CONFIG_HFSPLUS_FS_POSIX_ACL kernel configuration option, DBG_ACL_MOD
debugging flag and acl.h file with declaration of essential functions
for support POSIX ACLs in hfsplus driver.

Signed-off-by: Vyacheslav Dubeyko 
Cc: Al Viro 
Cc: Christoph Hellwig 
Cc: Hin-Tak Leung 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds