linux-stable.git/fs/ext4, branch v3.16.72

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

ext4: fix data corruption caused by unaligned direct AIO

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

commit 372a03e01853f860560eade508794dd274e9b390 upstream.

Ext4 needs to serialize unaligned direct AIO because the zeroing of
partial blocks of two competing unaligned AIOs can result in data
corruption.

However it decides not to serialize if the potentially unaligned aio is
past i_size with the rationale that no pending writes are possible past
i_size. Unfortunately if the i_size is not block aligned and the second
unaligned write lands past i_size, but still into the same block, it has
the potential of corrupting the previous unaligned write to the same
block.

This is (very simplified) reproducer from Frank

    // 41472 = (10 * 4096) + 512
    // 37376 = 41472 - 4096

    ftruncate(fd, 41472);
    io_prep_pwrite(iocbs[0], fd, buf[0], 4096, 37376);
    io_prep_pwrite(iocbs[1], fd, buf[1], 4096, 41472);

    io_submit(io_ctx, 1, &iocbs[1]);
    io_submit(io_ctx, 1, &iocbs[2]);

    io_getevents(io_ctx, 2, 2, events, NULL);

Without this patch the 512B range from 40960 up to the start of the
second unaligned write (41472) is going to be zeroed overwriting the data
written by the first write. This is a data corruption.

00000000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
*
00009200  30 30 30 30 30 30 30 30  30 30 30 30 30 30 30 30
*
0000a000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
*
0000a200  31 31 31 31 31 31 31 31  31 31 31 31 31 31 31 31

With this patch the data corruption is avoided because we will recognize
the unaligned_aio and wait for the unwritten extent conversion.

00000000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
*
00009200  30 30 30 30 30 30 30 30  30 30 30 30 30 30 30 30
*
0000a200  31 31 31 31 31 31 31 31  31 31 31 31 31 31 31 31
*
0000b200

Reported-by: Frank Sorenson 
Signed-off-by: Lukas Czerner 
Signed-off-by: Theodore Ts'o 
Fixes: e9e3bcecf44c ("ext4: serialize unaligned asynchronous DIO")
Signed-off-by: Ben Hutchings

ext4: fix crash during online resizing

2019-07-09T21:03:59+00:00

commit f96c3ac8dfc24b4e38fc4c2eba5fea2107b929d1 upstream.

When computing maximum size of filesystem possible with given number of
group descriptor blocks, we forget to include s_first_data_block into
the number of blocks. Thus for filesystems with non-zero
s_first_data_block it can happen that computed maximum filesystem size
is actually lower than current filesystem size which confuses the code
and eventually leads to a BUG_ON in ext4_alloc_group_tables() hitting on
flex_gd->count == 0. The problem can be reproduced like:

truncate -s 100g /tmp/image
mkfs.ext4 -b 1024 -E resize=262144 /tmp/image 32768
mount -t ext4 -o loop /tmp/image /mnt
resize2fs /dev/loop0 262145
resize2fs /dev/loop0 300000

Fix the problem by properly including s_first_data_block into the
computed number of filesystem blocks.

Fixes: 1c6bd7173d66 "ext4: convert file system to meta_bg if needed..."
Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Ben Hutchings

ext4: add mask of ext4 flags to swap

2019-07-09T21:03:58+00:00

commit abdc644e8cbac2e9b19763680e5a7cf9bab2bee7 upstream.

The reason is that while swapping two inode, we swap the flags too.
Some flags such as EXT4_JOURNAL_DATA_FL can really confuse the things
since we're not resetting the address operations structure.  The
simplest way to keep things sane is to restrict the flags that can be
swapped.

Signed-off-by: yangerkun 
Signed-off-by: Theodore Ts'o 
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings

ext4: update quota information while swapping boot loader inode

2019-07-09T21:03:58+00:00

commit aa507b5faf38784defe49f5e64605ac3c4425e26 upstream.

While do swap between two inode, they swap i_data without update
quota information. Also, swap_inode_boot_loader can do "revert"
somtimes, so update the quota while all operations has been finished.

Signed-off-by: yangerkun 
Signed-off-by: Theodore Ts'o 
[bwh: Backported to 3.16:
 - Include 
 - dquot_initialize() does not return an erro
 - Adjust context]
Signed-off-by: Ben Hutchings

ext4: fix check of inode in swap_inode_boot_loader

2019-07-09T21:03:57+00:00

commit 67a11611e1a5211f6569044fbf8150875764d1d0 upstream.

Before really do swap between inode and boot inode, something need to
check to avoid invalid or not permitted operation, like does this inode
has inline data. But the condition check should be protected by inode
lock to avoid change while swapping. Also some other condition will not
change between swapping, but there has no problem to do this under inode
lock.

Signed-off-by: yangerkun 
Signed-off-by: Theodore Ts'o 
[bwh: Backported to 3.16: There's no support or test for filesytem encryption]
Signed-off-by: Ben Hutchings

ext4: zero out the unused memory region in the extent tree block

2019-06-20T17:11:27+00:00

commit 592acbf16821288ecdc4192c47e3774a4c48bb64 upstream.

This commit zeroes out the unused memory region in the buffer_head
corresponding to the extent metablock after writing the extent header
and the corresponding extent node entries.

This is done to prevent random uninitialized data from getting into
the filesystem when the extent block is synced.

This fixes CVE-2019-11833.

Signed-off-by: Sriram Rajagopalan 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Ben Hutchings

ext4: fix special inode number checks in __ext4_iget()

2019-04-04T15:14:10+00:00

commit 191ce17876c9367819c4b0a25b503c0f6d9054d8 upstream.

The check for special (reserved) inode number checks in __ext4_iget()
was broken by commit 8a363970d1dc: ("ext4: avoid declaring fs
inconsistent due to invalid file handles").  This was caused by a
botched reversal of the sense of the flag now known as
EXT4_IGET_SPECIAL (when it was previously named EXT4_IGET_NORMAL).
Fix the logic appropriately.

Fixes: 8a363970d1dc ("ext4: avoid declaring fs inconsistent...")
Signed-off-by: Theodore Ts'o 
Reported-by: Dan Carpenter 
Signed-off-by: Ben Hutchings

ext4: avoid kernel warning when writing the superblock to a dead device

2019-04-04T15:14:09+00:00

commit e86807862e6880809f191c4cea7f88a489f0ed34 upstream.

The xfstests generic/475 test switches the underlying device with
dm-error while running a stress test.  This results in a large number
of file system errors, and since we can't lock the buffer head when
marking the superblock dirty in the ext4_grp_locked_error() case, it's
possible the superblock to be !buffer_uptodate() without
buffer_write_io_error() being true.

We need to set buffer_uptodate() before we call mark_buffer_dirty() or
this will trigger a WARN_ON.  It's safe to do this since the
superblock must have been properly read into memory or the mount would
have been successful.  So if buffer_uptodate() is not set, we can
safely assume that this happened due to a failed attempt to write the
superblock.

Signed-off-by: Theodore Ts'o 
Signed-off-by: Ben Hutchings

ext4: fix a potential fiemap/page fault deadlock w/ inline_data

2019-04-04T15:14:06+00:00

commit 2b08b1f12cd664dc7d5c84ead9ff25ae97ad5491 upstream.

The ext4_inline_data_fiemap() function calls fiemap_fill_next_extent()
while still holding the xattr semaphore.  This is not necessary and it
triggers a circular lockdep warning.  This is because
fiemap_fill_next_extent() could trigger a page fault when it writes
into page which triggers a page fault.  If that page is mmaped from
the inline file in question, this could very well result in a
deadlock.

This problem can be reproduced using generic/519 with a file system
configuration which has the inline_data feature enabled.

Signed-off-by: Theodore Ts'o 
Signed-off-by: Ben Hutchings