linux.git/fs, branch v3.0.82

jfs: fix a couple races

2013-06-07T19:46:48+00:00

commit 73aaa22d5ffb2630456bac2f9a4ed9b81d0d7271 upstream.

This patch fixes races uncovered by xfstests testcase 068.

One race is the result of jfs_sync() trying to write a sync point to the
journal after it has been frozen (or possibly in the process). Since
freezing sync's the journal, there is no need to write a sync point so
we simply want to return.

The second involves jfs_write_inode() being called on a deleted inode.
It calls jfs_flush_journal which is held up by the jfs_commit thread
doing the final iput on the same deleted inode, which itself is
waiting for the I_SYNC flag to be cleared. jfs_write_inode need not
do anything when i_nlink is zero, which is the easy fix.

Reported-by: Michael L. Semon 
Signed-off-by: Dave Kleikamp 
Signed-off-by: Greg Kroah-Hartman

cifs: fix potential buffer overrun when composing a new options string

2013-06-07T19:46:48+00:00

commit 166faf21bd14bc5c5295a44874bf7f3930c30b20 upstream.

Consider the case where we have a very short ip= string in the original
mount options, and when we chase a referral we end up with a very long
IPv6 address. Be sure to allow for that possibility when estimating the
size of the string to allocate.

Signed-off-by: Jeff Layton 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

nilfs2: fix issue of nilfs_set_page_dirty() for page at EOF boundary

2013-06-07T19:46:36+00:00

commit 136e8770cd5d1fe38b3c613100dd6dc4db6d4fa6 upstream.

nilfs2: fix issue of nilfs_set_page_dirty for page at EOF boundary

DESCRIPTION:
 There are use-cases when NILFS2 file system (formatted with block size
lesser than 4 KB) can be remounted in RO mode because of encountering of
"broken bmap" issue.

The issue was reported by Anthony Doggett :
 "The machine I've been trialling nilfs on is running Debian Testing,
  Linux version 3.2.0-4-686-pae (debian-kernel@lists.debian.org) (gcc
  version 4.6.3 (Debian 4.6.3-14) ) #1 SMP Debian 3.2.35-2), but I've
  also reproduced it (identically) with Debian Unstable amd64 and Debian
  Experimental (using the 3.8-trunk kernel).  The problematic partitions
  were formatted with "mkfs.nilfs2 -b 1024 -B 8192"."

SYMPTOMS:
(1) System log contains error messages likewise:

    [63102.496756] nilfs_direct_assign: invalid pointer: 0
    [63102.496786] NILFS error (device dm-17): nilfs_bmap_assign: broken bmap (inode number=28)
    [63102.496798]
    [63102.524403] Remounting filesystem read-only

(2) The NILFS2 file system is remounted in RO mode.

REPRODUSING PATH:
(1) Create volume group with name "unencrypted" by means of vgcreate utility.
(2) Run script (prepared by Anthony Doggett ):

----------------[BEGIN SCRIPT]--------------------

VG=unencrypted
lvcreate --size 2G --name ntest $VG
mkfs.nilfs2 -b 1024 -B 8192 /dev/mapper/$VG-ntest
mkdir /var/tmp/n
mkdir /var/tmp/n/ntest
mount /dev/mapper/$VG-ntest /var/tmp/n/ntest
mkdir /var/tmp/n/ntest/thedir
cd /var/tmp/n/ntest/thedir
sleep 2
date
darcs init
sleep 2
dmesg|tail -n 5
date
darcs whatsnew || true
date
sleep 2
dmesg|tail -n 5
----------------[END SCRIPT]--------------------

REPRODUCIBILITY: 100%

INVESTIGATION:
As it was discovered, the issue takes place during segment
construction after executing such sequence of user-space operations:

  open("_darcs/index", O_RDWR|O_CREAT|O_NOCTTY, 0666) = 7
  fstat(7, {st_mode=S_IFREG|0644, st_size=0, ...}) = 0
  ftruncate(7, 60)

The error message "NILFS error (device dm-17): nilfs_bmap_assign: broken
bmap (inode number=28)" takes place because of trying to get block
number for third block of the file with logical offset #3072 bytes.  As
it is possible to see from above output, the file has 60 bytes of the
whole size.  So, it is enough one block (1 KB in size) allocation for
the whole file.  Trying to operate with several blocks instead of one
takes place because of discovering several dirty buffers for this file
in nilfs_segctor_scan_file() method.

The root cause of this issue is in nilfs_set_page_dirty function which
is called just before writing to an mmapped page.

When nilfs_page_mkwrite function handles a page at EOF boundary, it
fills hole blocks only inside EOF through __block_page_mkwrite().

The __block_page_mkwrite() function calls set_page_dirty() after filling
hole blocks, thus nilfs_set_page_dirty function (=
a_ops->set_page_dirty) is called.  However, the current implementation
of nilfs_set_page_dirty() wrongly marks all buffers dirty even for page
at EOF boundary.

As a result, buffers outside EOF are inconsistently marked dirty and
queued for write even though they are not mapped with nilfs_get_block
function.

FIX:
This modifies nilfs_set_page_dirty() not to mark hole blocks dirty.

Thanks to Vyacheslav Dubeyko for his effort on analysis and proposals
for this issue.

Signed-off-by: Ryusuke Konishi 
Reported-by: Anthony Doggett 
Reported-by: Vyacheslav Dubeyko 
Cc: Vyacheslav Dubeyko 
Tested-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ocfs2: goto out_unlock if ocfs2_get_clusters_nocache() failed in ocfs2_fiemap()

2013-06-07T19:46:36+00:00

commit b4ca2b4b577c3530e34dcfaafccb2cc680ce95d1 upstream.

Last time we found there is lock/unlock bug in ocfs2_file_aio_write, and
then we did a thorough search for all lock resources in
ocfs2_inode_info, including rw, inode and open lockres and found this
bug.  My kernel version is 3.0.13, and it is also in the lastest version
3.9.  In ocfs2_fiemap, once ocfs2_get_clusters_nocache failed, it should
goto out_unlock instead of out, because we need release buffer head, up
read alloc sem and unlock inode.

Signed-off-by: Joseph Qi 
Reviewed-by: Jie Liu 
Cc: Mark Fasheh 
Cc: Joel Becker 
Acked-by: Sunil Mushran 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

fat: fix possible overflow for fat_clusters

2013-06-07T19:46:35+00:00

commit 7b92d03c3239f43e5b86c9cc9630f026d36ee995 upstream.

Intermediate value of fat_clusters can be overflowed on 32bits arch.

Reported-by: Krzysztof Strasburger 
Signed-off-by: OGAWA Hirofumi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

cifs: only set ops for inodes in I_NEW state

2013-06-07T19:46:35+00:00

commit c2b93e0699723700f886ce17bb65ffd771195a6d upstream.

It's generally not safe to reset the inode ops once they've been set. In
the case where the inode was originally thought to be a directory and
then later found to be a DFS referral, this can lead to an oops when we
try to trigger an inode op on it after changing the ops to the blank
referral operations.

Reported-and-Tested-by: Sachin Prabhu 
Signed-off-by: Jeff Layton 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

btrfs: don't stop searching after encountering the wrong item

2013-05-24T18:09:24+00:00

commit 03b71c6ca6286625d8f1ed44aabab9b5bf5dac10 upstream.

The search ioctl skips items that are too large for a result buffer, but
inline items of a certain size occuring before any search result is
found would trigger an overflow and stop the search entirely.

Bug: https://bugzilla.kernel.org/show_bug.cgi?id=57641

Signed-off-by: Gabriel de Perthuis 
Signed-off-by: Josef Bacik 
Signed-off-by: Greg Kroah-Hartman

ext4: limit group search loop for non-extent files

2013-05-19T17:04:40+00:00

commit e6155736ad76b2070652745f9e54cdea3f0d8567 upstream.

In the case where we are allocating for a non-extent file,
we must limit the groups we allocate from to those below
2^32 blocks, and ext4_mb_regular_allocator() attempts to
do this initially by putting a cap on ngroups for the
subsequent search loop.

However, the initial target group comes in from the
allocation context (ac), and it may already be beyond
the artificially limited ngroups.  In this case,
the limit

	if (group == ngroups)
		group = 0;

at the top of the loop is never true, and the loop will
run away.

Catch this case inside the loop and reset the search to
start at group 0.

[sandeen@redhat.com: add commit msg & comments]

Signed-off-by: Lachlan McIlroy 
Signed-off-by: Eric Sandeen 
Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

autofs - remove autofs dentry mount check

2013-05-11T20:38:00+00:00

commit ce8a5dbdf9e709bdaf4618d7ef8cceb91e8adc69 upstream.

When checking if an autofs mount point is busy it isn't sufficient to
only check if it's a mount point.

For example, if the mount of an offset mountpoint in a tree is denied
for this host by its export and the dentry becomes a process working
directory the check incorrectly returns the mount as not in use at
expire.

This can happen since the default when mounting within a tree is
nostrict, which means ingnore mount fails on mounts within the tree and
continue.  The nostrict option is meant to allow mounting in this case.

Signed-off-by: David Jeffery 
Signed-off-by: Ian Kent 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ext4: fix Kconfig documentation for CONFIG_EXT4_DEBUG

2013-05-08T02:57:27+00:00

commit 7f3e3c7cfcec148ccca9c0dd2dbfd7b00b7ac10f upstream.

Fox the Kconfig documentation for CONFIG_EXT4_DEBUG to match the
change made by commit a0b30c1229: ext4: use module parameters instead
of debugfs for mballoc_debug

Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman