linux-stable.git/fs/ext4, branch v3.12.28

ext4: fix ext4_discard_allocated_blocks() if we can't allocate the pa struct

2014-09-03T19:31:24+00:00

commit 86f0afd463215fc3e58020493482faa4ac3a4d69 upstream.

If there is a failure while allocating the preallocation structure, a
number of blocks can end up getting marked in the in-memory buddy
bitmap, and then not getting released.  This can result in the
following corruption getting reported by the kernel:

EXT4-fs error (device sda3): ext4_mb_generate_buddy:758: group 1126,
12793 clusters in bitmap, 12729 in gd

In that case, we need to release the blocks using mb_free_blocks().

Tested: fs smoke test; also demonstrated that with injected errors,
	the file system is no longer getting corrupted

Google-Bug-Id: 16657874

Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Jiri Slaby

ext4: Fix block zeroing when punching holes in indirect block files

2014-08-26T12:12:06+00:00

commit 77ea2a4ba657a1ad4fb7c64bc5cdce84b8a132b6 upstream.

free_holes_block() passed local variable as a block pointer
to ext4_clear_blocks(). Thus ext4_clear_blocks() zeroed out this local
variable instead of proper place in inode / indirect block. We later
zero out proper place in inode / indirect block but don't dirty the
inode / buffer again which can lead to subtle issues (some changes e.g.
to inode can be lost).

Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jiri Slaby

ext4: fix a potential deadlock in __ext4_es_shrink()

2014-07-18T13:51:27+00:00

commit 3f1f9b851311a76226140b55b1ea22111234a7c2 upstream.

This fixes the following lockdep complaint:

[ INFO: possible circular locking dependency detected ]
3.16.0-rc2-mm1+ #7 Tainted: G           O
-------------------------------------------------------
kworker/u24:0/4356 is trying to acquire lock:
 (&(&sbi->s_es_lru_lock)->rlock){+.+.-.}, at: [] __ext4_es_shrink+0x4f/0x2e0

but task is already holding lock:
 (&ei->i_es_lock){++++-.}, at: [] ext4_es_insert_extent+0x71/0x180

which lock already depends on the new lock.

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ei->i_es_lock);
                               lock(&(&sbi->s_es_lru_lock)->rlock);
                               lock(&ei->i_es_lock);
  lock(&(&sbi->s_es_lru_lock)->rlock);

 *** DEADLOCK ***

6 locks held by kworker/u24:0/4356:
 #0:  ("writeback"){.+.+.+}, at: [] process_one_work+0x180/0x560
 #1:  ((&(&wb->dwork)->work)){+.+.+.}, at: [] process_one_work+0x180/0x560
 #2:  (&type->s_umount_key#22){++++++}, at: [] grab_super_passive+0x44/0x90
 #3:  (jbd2_handle){+.+...}, at: [] start_this_handle+0x189/0x5f0
 #4:  (&ei->i_data_sem){++++..}, at: [] ext4_map_blocks+0x132/0x550
 #5:  (&ei->i_es_lock){++++-.}, at: [] ext4_es_insert_extent+0x71/0x180

stack backtrace:
CPU: 0 PID: 4356 Comm: kworker/u24:0 Tainted: G           O   3.16.0-rc2-mm1+ #7
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Workqueue: writeback bdi_writeback_workfn (flush-253:0)
 ffffffff8213dce0 ffff880014b07538 ffffffff815df0bb 0000000000000007
 ffffffff8213e040 ffff880014b07588 ffffffff815db3dd ffff880014b07568
 ffff880014b07610 ffff88003b868930 ffff88003b868908 ffff88003b868930
Call Trace:
 [] dump_stack+0x4e/0x68
 [] print_circular_bug+0x1fb/0x20c
 [] __lock_acquire+0x163e/0x1d00
 [] ? retint_restore_args+0xe/0xe
 [] ? __slab_alloc+0x4a8/0x4ce
 [] ? __ext4_es_shrink+0x4f/0x2e0
 [] lock_acquire+0x87/0x120
 [] ? __ext4_es_shrink+0x4f/0x2e0
 [] ? ext4_es_free_extent+0x5d/0x70
 [] _raw_spin_lock+0x39/0x50
 [] ? __ext4_es_shrink+0x4f/0x2e0
 [] ? kmem_cache_alloc+0x18b/0x1a0
 [] __ext4_es_shrink+0x4f/0x2e0
 [] ext4_es_insert_extent+0xc8/0x180
 [] ext4_map_blocks+0x1c4/0x550
 [] ext4_writepages+0x6d4/0xd00
	...

Reported-by: Minchan Kim 
Signed-off-by: Theodore Ts'o 
Reported-by: Minchan Kim 
Cc: Zheng Liu 
Signed-off-by: Jiri Slaby

ext4: disable synchronous transaction batching if max_batch_time==0

2014-07-18T13:51:26+00:00

commit 5dd214248f94d430d70e9230bda72f2654ac88a8 upstream.

The mount manpage says of the max_batch_time option,

	This optimization can be turned off entirely
	by setting max_batch_time to 0.

But the code doesn't do that.  So fix the code to do
that.

Signed-off-by: Eric Sandeen 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jiri Slaby

ext4: clarify ext4_error message in ext4_mb_generate_buddy_error()

2014-07-18T13:51:26+00:00

commit 94d4c066a4ff170a2671b1a9b153febbf36796f6 upstream.

We are spending a lot of time explaining to users what this error
means.  Let's try to improve the message to avoid this problem.

Signed-off-by: Theodore Ts'o 
Signed-off-by: Jiri Slaby

ext4: clarify error count warning messages

2014-07-18T13:51:25+00:00

commit ae0f78de2c43b6fadd007c231a352b13b5be8ed2 upstream.

Make it clear that values printed are times, and that it is error
since last fsck. Also add note about fsck version required.

Signed-off-by: Pavel Machek 
Signed-off-by: Theodore Ts'o 
Reviewed-by: Andreas Dilger 
Signed-off-by: Jiri Slaby

ext4: fix unjournalled bg descriptor while initializing inode bitmap

2014-07-18T13:51:25+00:00

commit 61c219f5814277ecb71d64cb30297028d6665979 upstream.

The first time that we allocate from an uninitialized inode allocation
bitmap, if the block allocation bitmap is also uninitalized, we need
to get write access to the block group descriptor before we start
modifying the block group descriptor flags and updating the free block
count, etc.  Otherwise, there is the potential of a bad journal
checksum (if journal checksums are enabled), and of the file system
becoming inconsistent if we crash at exactly the wrong time.

Signed-off-by: Theodore Ts'o 
Signed-off-by: Jiri Slaby

ext4: Fix hole punching for files with indirect blocks

2014-07-18T13:51:05+00:00

commit a93cd4cf86466caa49cfe64607bea7f0bde3f916 upstream.

Hole punching code for files with indirect blocks wrongly computed
number of blocks which need to be cleared when traversing the indirect
block tree. That could result in punching more blocks than actually
requested and thus effectively cause a data loss. For example:

fallocate -n -p 10240000 4096

will punch the range 10240000 - 12632064 instead of the range 1024000 -
10244096. Fix the calculation.

Fixes: 8bad6fc813a3a5300f51369c39d315679fd88c72
Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jiri Slaby

ext4: Fix buffer double free in ext4_alloc_branch()

2014-07-18T13:51:04+00:00

commit c5c7b8ddfbf8cb3b2291e515a34ab1b8982f5a2d upstream.

Error recovery in ext4_alloc_branch() calls ext4_forget() even for
buffer corresponding to indirect block it did not allocate. This leads
to brelse() being called twice for that buffer (once from ext4_forget()
and once from cleanup in ext4_ind_map_blocks()) leading to buffer use
count misaccounting. Eventually (but often much later because there
are other users of the buffer) we will see messages like:
VFS: brelse: Trying to free free buffer

Another manifestation of this problem is an error:
JBD2 unexpected failure: jbd2_journal_revoke: !buffer_revoked(bh);
inconsistent data on disk

The fix is easy - don't forget buffer we did not allocate. Also add an
explanatory comment because the indexing at ext4_alloc_branch() is
somewhat subtle.

Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jiri Slaby

ext4: fix wrong assert in ext4_mb_normalize_request()

2014-07-02T10:06:16+00:00

commit b5b60778558cafad17bbcbf63e0310bd3c68eb17 upstream.

The variable "size" is expressed as number of blocks and not as
number of clusters, this could trigger a kernel panic when using
ext4 with the size of a cluster different from the size of a block.

Signed-off-by: Maurizio Lombardi 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jiri Slaby