linux-toradex.git/fs, branch v3.0.88

lockd: protect nlm_blocked access in nlmsvc_retry_blocked

2013-07-28T23:18:48+00:00

commit 1c327d962fc420aea046c16215a552710bde8231 upstream.

In nlmsvc_retry_blocked, the check that the list is non-empty and acquiring
the pointer of the first entry is unprotected by any lock.  This allows a rare
race condition when there is only one entry on the list.  A function such as
nlmsvc_grant_callback() can be called, which will temporarily remove the entry
from the list.  Between the list_empty() and list_entry(),the list may become
empty, causing an invalid pointer to be used as an nlm_block, leading to a
possible crash.

This patch adds the nlm_block_lock around these calls to prevent concurrent
use of the nlm_blocked list.

This was a regression introduced by
f904be9cc77f361d37d71468b13ff3d1a1823dea  "lockd: Mostly remove BKL from
the server".

Signed-off-by: David Jeffery 
Cc: Bryan Schumaker 
Signed-off-by: J. Bruce Fields 
Signed-off-by: Greg Kroah-Hartman

writeback: Fix periodic writeback after fs mount

2013-07-28T23:18:44+00:00

commit a5faeaf9109578e65e1a32e2a3e76c8b47e7dcb6 upstream.

Code in blkdev.c moves a device inode to default_backing_dev_info when
the last reference to the device is put and moves the device inode back
to its bdi when the first reference is acquired. This includes moving to
wb.b_dirty list if the device inode is dirty. The code however doesn't
setup timer to wake corresponding flusher thread and while wb.b_dirty
list is non-empty __mark_inode_dirty() will not set it up either. Thus
periodic writeback is effectively disabled until a sync(2) call which can
lead to unexpected data loss in case of crash or power failure.

Fix the problem by setting up a timer for periodic writeback in case we
add the first dirty inode to wb.b_dirty list in bdev_inode_switch_bdi().

Reported-by: Bert De Jonghe 
Signed-off-by: Jan Kara 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

ext4: fix overflow when counting used blocks on 32-bit architectures

2013-07-22T01:14:41+00:00

commit 8af8eecc1331dbf5e8c662022272cf667e213da5 upstream.

The arithmetics adding delalloc blocks to the number of used blocks in
ext4_getattr() can easily overflow on 32-bit archs as we first multiply
number of blocks by blocksize and then divide back by 512. Make the
arithmetics more clever and also use proper type (unsigned long long
instead of unsigned long).

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

ext4: fix data offset overflow in ext4_xattr_fiemap() on 32-bit archs

2013-07-22T01:14:41+00:00

commit a60697f411eb365fb09e639e6f183fe33d1eb796 upstream.

On 32-bit architectures with 32-bit sector_t computation of data offset
in ext4_xattr_fiemap() can overflow resulting in reporting bogus data
location. Fix the problem by typing block number to proper type before
shifting.

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

ocfs2: xattr: fix inlined xattr reflink

2013-07-22T01:14:41+00:00

commit ef962df057aaafd714f5c22ba3de1be459571fdf upstream.

Inlined xattr shared free space of inode block with inlined data or data
extent record, so the size of the later two should be adjusted when
inlined xattr is enabled.  See ocfs2_xattr_ibody_init().  But this isn't
done well when reflink.  For inode with inlined data, its max inlined
data size is adjusted in ocfs2_duplicate_inline_data(), no problem.  But
for inode with data extent record, its record count isn't adjusted.  Fix
it, or data extent record and inlined xattr may overwrite each other,
then cause data corruption or xattr failure.

One panic caused by this bug in our test environment is the following:

  kernel BUG at fs/ocfs2/xattr.c:1435!
  invalid opcode: 0000 [#1] SMP
  Pid: 10871, comm: multi_reflink_t Not tainted 2.6.39-300.17.1.el5uek #1
  RIP: ocfs2_xa_offset_pointer+0x17/0x20 [ocfs2]
  RSP: e02b:ffff88007a587948  EFLAGS: 00010283
  RAX: 0000000000000000 RBX: 0000000000000010 RCX: 00000000000051e4
  RDX: ffff880057092060 RSI: 0000000000000f80 RDI: ffff88007a587a68
  RBP: ffff88007a587948 R08: 00000000000062f4 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000010
  R13: ffff88007a587a68 R14: 0000000000000001 R15: ffff88007a587c68
  FS:  00007fccff7f06e0(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000
  CS:  e033 DS: 0000 ES: 0000 CR0: 000000008005003b
  CR2: 00000000015cf000 CR3: 000000007aa76000 CR4: 0000000000000660
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
  Process multi_reflink_t
  Call Trace:
    ocfs2_xa_reuse_entry+0x60/0x280 [ocfs2]
    ocfs2_xa_prepare_entry+0x17e/0x2a0 [ocfs2]
    ocfs2_xa_set+0xcc/0x250 [ocfs2]
    ocfs2_xattr_ibody_set+0x98/0x230 [ocfs2]
    __ocfs2_xattr_set_handle+0x4f/0x700 [ocfs2]
    ocfs2_xattr_set+0x6c6/0x890 [ocfs2]
    ocfs2_xattr_user_set+0x46/0x50 [ocfs2]
    generic_setxattr+0x70/0x90
    __vfs_setxattr_noperm+0x80/0x1a0
    vfs_setxattr+0xa9/0xb0
    setxattr+0xc3/0x120
    sys_fsetxattr+0xa8/0xd0
    system_call_fastpath+0x16/0x1b

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

ext3,ext4: don't mess with dir_file->f_pos in htree_dirblock_to_tree()

2013-07-22T01:14:40+00:00

commit 64cb927371cd2ec43758d8a094a003d27bc3d0dc upstream.

Both ext3 and ext4 htree_dirblock_to_tree() is just filling the
in-core rbtree for use by call_filldir().  All updates of ->f_pos are
done by the latter; bumping it here (on error) is obviously wrong - we
might very well have it nowhere near the block we'd found an error in.

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

jbd2: fix theoretical race in jbd2__journal_restart

2013-07-22T01:14:40+00:00

commit 39c04153fda8c32e85b51c96eb5511a326ad7609 upstream.

Once we decrement transaction->t_updates, if this is the last handle
holding the transaction from closing, and once we release the
t_handle_lock spinlock, it's possible for the transaction to commit
and be released.  In practice with normal kernels, this probably won't
happen, since the commit happens in a separate kernel thread and it's
unlikely this could all happen within the space of a few CPU cycles.

On the other hand, with a real-time kernel, this could potentially
happen, so save the tid found in transaction->t_tid before we release
t_handle_lock.  It would require an insane configuration, such as one
where the jbd2 thread was set to a very high real-time priority,
perhaps because a high priority real-time thread is trying to read or
write to a file system.  But some people who use real-time kernels
have been known to do insane things, including controlling
laser-wielding industrial robots.  :-)

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

nfsd4: fix decoding of compounds across page boundaries

2013-07-13T17:34:44+00:00

commit 247500820ebd02ad87525db5d9b199e5b66f6636 upstream.

A freebsd NFSv4.0 client was getting rare IO errors expanding a tarball.
A network trace showed the server returning BAD_XDR on the final getattr
of a getattr+write+getattr compound.  The final getattr started on a
page boundary.

I believe the Linux client ignores errors on the post-write getattr, and
that that's why we haven't seen this before.

Reported-by: Rick Macklem 
Signed-off-by: J. Bruce Fields 
Signed-off-by: Greg Kroah-Hartman

hpfs: better test for errors

2013-07-13T17:34:43+00:00

commit 3ebacb05044f82c5f0bb456a894eb9dc57d0ed90 upstream.

The test if bitmap access is out of bound could errorneously pass if the
device size is divisible by 16384 sectors and we are asking for one bitmap
after the end.

Check for invalid size in the superblock. Invalid size could cause integer
overflows in the rest of the code.

Signed-off-by: Mikulas Patocka 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

UBIFS: fix a horrid bug

2013-07-03T18:03:24+00:00

commit 605c912bb843c024b1ed173dc427cd5c08e5d54d upstream.

Al Viro pointed me to the fact that '->readdir()' and '->llseek()' have no
mutual exclusion, which means the 'ubifs_dir_llseek()' can be run while we are
in the middle of 'ubifs_readdir()'.

This means that 'file->private_data' can be freed while 'ubifs_readdir()' uses
it, and this is a very bad bug: not only 'ubifs_readdir()' can return garbage,
but this may corrupt memory and lead to all kinds of problems like crashes an
security holes.

This patch fixes the problem by using the 'file->f_version' field, which
'->llseek()' always unconditionally sets to zero. We set it to 1 in
'ubifs_readdir()' and whenever we detect that it became 0, we know there was a
seek and it is time to clear the state saved in 'file->private_data'.

I tested this patch by writing a user-space program which runds readdir and
seek in parallell. I could easily crash the kernel without these patches, but
could not crash it with these patches.

Reported-by: Al Viro 
Tested-by: Artem Bityutskiy 
Signed-off-by: Artem Bityutskiy 
Signed-off-by: Al Viro 
Signed-off-by: Greg Kroah-Hartman