linux-stable.git/fs/ext4, branch v3.16.82

ext4: work around deleting a file with i_nlink == 0 safely

2020-02-11T20:03:44+00:00

commit c7df4a1ecb8579838ec8c56b2bb6a6716e974f37 upstream.

If the file system is corrupted such that a file's i_links_count is
too small, then it's possible that when unlinking that file, i_nlink
will already be zero.  Previously we were working around this kind of
corruption by forcing i_nlink to one; but we were doing this before
trying to delete the directory entry --- and if the file system is
corrupted enough that ext4_delete_entry() fails, then we exit with
i_nlink elevated, and this causes the orphan inode list handling to be
FUBAR'ed, such that when we unmount the file system, the orphan inode
list can get corrupted.

A better way to fix this is to simply skip trying to call drop_nlink()
if i_nlink is already zero, thus moving the check to the place where
it makes the most sense.

https://bugzilla.kernel.org/show_bug.cgi?id=205433

Link: https://lore.kernel.org/r/20191112032903.8828-1-tytso@mit.edu
Signed-off-by: Theodore Ts'o 
Reviewed-by: Andreas Dilger 
[bwh: Backported to 3.16: Log message and function are different]
Signed-off-by: Ben Hutchings

ext4: add more paranoia checking in ext4_expand_extra_isize handling

2020-01-11T02:05:04+00:00

commit 4ea99936a1630f51fc3a2d61a58ec4a1c4b7d55a upstream.

It's possible to specify a non-zero s_want_extra_isize via debugging
option, and this can cause bad things(tm) to happen when using a file
system with an inode size of 128 bytes.

Add better checking when the file system is mounted, as well as when
we are actually doing the trying to do the inode expansion.

Link: https://lore.kernel.org/r/20191110121510.GH23325@mit.edu
Reported-by: syzbot+f8d6f8386ceacdbfff57@syzkaller.appspotmail.com
Reported-by: syzbot+33d7ea72e47de3bdf4e1@syzkaller.appspotmail.com
Reported-by: syzbot+44b6763edfc17144296f@syzkaller.appspotmail.com
Signed-off-by: Theodore Ts'o 
[bwh: Backported to 3.16:
 - Use EIO instead of EFSCORRUPTED
 - Adjust context]
Signed-off-by: Ben Hutchings

ext4: Introduce ext4_clamp_want_extra_isize()

2020-01-11T02:05:03+00:00

Based on commit 7bc04c5c2cc4 "ext4: fix use-after-free race with
debug_want_extra_isize".  We don't have that bug but this will make it
easier to backport commit 4ea99936a163 "ext4: add more paranoia
checking in ext4_expand_extra_isize handling".

Cc: Barret Rhoden 
Cc: Theodore Ts'o 
Signed-off-by: Ben Hutchings

ext4: fix warning inside ext4_convert_unwritten_extents_endio

2019-12-10T18:01:14+00:00

commit e3d550c2c4f2f3dba469bc3c4b83d9332b4e99e1 upstream.

Really enable warning when CONFIG_EXT4_DEBUG is set and fix missing
first argument.  This was introduced in commit ff95ec22cd7f ("ext4:
add warning to ext4_convert_unwritten_extents_endio") and splitting
extents inside endio would trigger it.

Fixes: ff95ec22cd7f ("ext4: add warning to ext4_convert_unwritten_extents_endio")
Signed-off-by: Rakesh Pandit 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Ben Hutchings

ext4: set error return correctly when ext4_htree_store_dirent fails

2019-12-10T18:01:12+00:00

commit 7a14826ede1d714f0bb56de8167c0e519041eeda upstream.

Currently when the call to ext4_htree_store_dirent fails the error return
variable 'ret' is is not being set to the error code and variable count is
instead, hence the error code is not being returned.  Fix this by assigning
ret to the error return code.

Addresses-Coverity: ("Unused value")
Fixes: 8af0f0822797 ("ext4: fix readdir error in the case of inline_data+dir_index")
Signed-off-by: Colin Ian King 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Ben Hutchings

ext4: fix data corruption caused by overlapping unaligned and aligned IO

2019-09-23T20:12:04+00:00

commit 57a0da28ced8707cb9f79f071a016b9d005caf5a upstream.

Unaligned AIO must be serialized because the zeroing of partial blocks
of unaligned AIO can result in data corruption in case it's overlapping
another in flight IO.

Currently we wait for all unwritten extents before we submit unaligned
AIO which protects data in case of unaligned AIO is following overlapping
IO. However if a unaligned AIO is followed by overlapping aligned AIO we
can still end up corrupting data.

To fix this, we must make sure that the unaligned AIO is the only IO in
flight by waiting for unwritten extents conversion not just before the
IO submission, but right after it as well.

This problem can be reproduced by xfstest generic/538

Signed-off-by: Lukas Czerner 
Signed-off-by: Theodore Ts'o 
[bwh: Backported to 3.16:
 - Test aio_mutex instead of unaligned_aio
 - Adjust context]
Signed-off-by: Ben Hutchings

ext4: actually request zeroing of inode table after grow

2019-09-23T20:11:53+00:00

commit 310a997fd74de778b9a4848a64be9cda9f18764a upstream.

It is never possible, that number of block groups decreases,
since only online grow is supported.

But after a growing occured, we have to zero inode tables
for just created new block groups.

Fixes: 19c5246d2516 ("ext4: add new online resize interface")
Signed-off-by: Kirill Tkhai 
Signed-off-by: Theodore Ts'o 
Reviewed-by: Jan Kara 
Signed-off-by: Ben Hutchings

ext4: cleanup bh release code in ext4_ind_remove_space()

2019-08-20T18:01:56+00:00

commit 5e86bdda41534e17621d5a071b294943cae4376e upstream.

Currently, we are releasing the indirect buffer where we are done with
it in ext4_ind_remove_space(), so we can see the brelse() and
BUFFER_TRACE() everywhere.  It seems fragile and hard to read, and we
may probably forget to release the buffer some day.  This patch cleans
up the code by putting of the code which releases the buffers to the
end of the function.

Signed-off-by: zhangyi (F) 
Signed-off-by: Theodore Ts'o 
Reviewed-by: Jan Kara 
Signed-off-by: Ben Hutchings

ext4: brelse all indirect buffer in ext4_ind_remove_space()

2019-08-20T18:01:56+00:00

commit 674a2b27234d1b7afcb0a9162e81b2e53aeef217 upstream.

All indirect buffers get by ext4_find_shared() should be released no
mater the branch should be freed or not. But now, we forget to release
the lower depth indirect buffers when removing space from the same
higher depth indirect block. It will lead to buffer leak and futher
more, it may lead to quota information corruption when using old quota,
consider the following case.

 - Create and mount an empty ext4 filesystem without extent and quota
   features,
 - quotacheck and enable the user & group quota,
 - Create some files and write some data to them, and then punch hole
   to some files of them, it may trigger the buffer leak problem
   mentioned above.
 - Disable quota and run quotacheck again, it will create two new
   aquota files and write the checked quota information to them, which
   probably may reuse the freed indirect block(the buffer and page
   cache was not freed) as data block.
 - Enable quota again, it will invoke
   vfs_load_quota_inode()->invalidate_bdev() to try to clean unused
   buffers and pagecache. Unfortunately, because of the buffer of quota
   data block is still referenced, quota code cannot read the up to date
   quota info from the device and lead to quota information corruption.

This problem can be reproduced by xfstests generic/231 on ext3 file
system or ext4 file system without extent and quota features.

This patch fix this problem by releasing the missing indirect buffers,
in ext4_ind_remove_space().

Reported-by: Hulk Robot 
Signed-off-by: zhangyi (F) 
Signed-off-by: Theodore Ts'o 
Reviewed-by: Jan Kara 
Signed-off-by: Ben Hutchings

ext4: add missing brelse() in add_new_gdb_meta_bg()

2019-08-13T11:38:41+00:00

commit d64264d6218e6892edd832dc3a5a5857c2856c53 upstream.

Currently in add_new_gdb_meta_bg() there is a missing brelse of gdb_bh
in case ext4_journal_get_write_access() fails.
Additionally kvfree() is missing in the same error path. Fix it by
moving the ext4_journal_get_write_access() before the ext4 sb update as
Ted suggested and release n_group_desc and gdb_bh in case it fails.

Fixes: 61a9c11e5e7a ("ext4: add missing brelse() add_new_gdb_meta_bg()'s error path")
Signed-off-by: Lukas Czerner 
Signed-off-by: Theodore Ts'o 
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings