linux-toradex.git/fs/ext4, branch v4.4.100

ext4: fix data exposure after a crash

2017-11-21T08:21:17+00:00

commit 06bd3c36a733ac27962fea7d6f47168841376824 upstream.

Huang has reported that in his powerfail testing he is seeing stale
block contents in some of recently allocated blocks although he mounts
ext4 in data=ordered mode. After some investigation I have found out
that indeed when delayed allocation is used, we don't add inode to
transaction's list of inodes needing flushing before commit. Originally
we were doing that but commit f3b59291a69d removed the logic with a
flawed argument that it is not needed.

The problem is that although for delayed allocated blocks we write their
contents immediately after allocating them, there is no guarantee that
the IO scheduler or device doesn't reorder things and thus transaction
allocating blocks and attaching them to inode can reach stable storage
before actual block contents. Actually whenever we attach freshly
allocated blocks to inode using a written extent, we should add inode to
transaction's ordered inode list to make sure we properly wait for block
contents to be written before committing the transaction. So that is
what we do in this patch. This also handles other cases where stale data
exposure was possible - like filling hole via mmap in
data=ordered,nodelalloc mode.

The only exception to the above rule are extending direct IO writes where
blkdev_direct_IO() waits for IO to complete before increasing i_size and
thus stale data exposure is not possible. For now we don't complicate
the code with optimizing this special case since the overhead is pretty
low. In case this is observed to be a performance problem we can always
handle it using a special flag to ext4_map_blocks().

Fixes: f3b59291a69d0b734be1fc8be489fef2dd846d3d
Reported-by: "HUANG Weller (CM/ESW12-CN)" 
Tested-by: "HUANG Weller (CM/ESW12-CN)" 
Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
[bwh: Backported to 4.4:
 - Drop check for EXT4_GET_BLOCKS_ZERO flag
 - Adjust context]
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

ext4: do not use stripe_width if it is not set

2017-11-08T09:06:29+00:00

[ Upstream commit 5469d7c3087ecaf760f54b447f11af6061b7c897 ]

Avoid using stripe_width for sbi->s_stripe value if it is not actually
set. It prevents using the stride for sbi->s_stripe.

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

ext4: fix stripe-unaligned allocations

2017-11-08T09:06:29+00:00

[ Upstream commit d9b22cf9f5466a057f2a4f1e642b469fa9d73117 ]

When a filesystem is created using:

	mkfs.ext4 -b 4096 -E stride=512 

and we try to allocate 64MB extent, we will end up directly in
ext4_mb_complex_scan_group(). This is because the request is detected
as power-of-two allocation (so we start in ext4_mb_regular_allocator()
with ac_criteria == 0) however the check before
ext4_mb_simple_scan_group() refuses the direct buddy scan because the
allocation request is too large. Since cr == 0, the check whether we
should use ext4_mb_scan_aligned() fails as well and we fall back to
ext4_mb_complex_scan_group().

Fix the problem by checking for upper limit on power-of-two requests
directly when detecting them.

Reported-by: Ross Zwisler 
Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

fscrypt: fix dereference of NULL user_key_payload

2017-10-27T08:23:18+00:00

commit d60b5b7854c3d135b869f74fb93eaf63cbb1991a upstream.

When an fscrypt-encrypted file is opened, we request the file's master
key from the keyrings service as a logon key, then access its payload.
However, a revoked key has a NULL payload, and we failed to check for
this.  request_key() *does* skip revoked keys, but there is still a
window where the key can be revoked before we acquire its semaphore.

Fix it by checking for a NULL payload, treating it like a key which was
already revoked at the time it was requested.

Fixes: 88bd6ccdcdd6 ("ext4 crypto: add encryption key management facilities")
Reviewed-by: James Morris 
Cc:     [v4.1+]
Signed-off-by: Eric Biggers 
Signed-off-by: David Howells 
Signed-off-by: Greg Kroah-Hartman

ext4: in ext4_seek_{hole,data}, return -ENXIO for negative offsets

2017-10-18T07:20:40+00:00

commit 1bd8d6cd3e413d64e543ec3e69ff43e75a1cf1ea upstream.

In the ext4 implementations of SEEK_HOLE and SEEK_DATA, make sure we
return -ENXIO for negative offsets instead of banging around inside
the extent code and returning -EFSCORRUPTED.

Reported-by: Mateusz S 
Signed-off-by: Darrick J. Wong 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: don't allow encrypted operations without keys

2017-10-12T09:27:35+00:00

commit 173b8439e1ba362007315868928bf9d26e5cc5a6 upstream.

While we allow deletes without the key, the following should not be
permitted:

# cd /vdc/encrypted-dir-without-key
# ls -l
total 4
-rw-r--r-- 1 root root   0 Dec 27 22:35 6,LKNRJsp209FbXoSvJWzB
-rw-r--r-- 1 root root 286 Dec 27 22:35 uRJ5vJh9gE7vcomYMqTAyD
# mv uRJ5vJh9gE7vcomYMqTAyD  6,LKNRJsp209FbXoSvJWzB

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

ext4: Don't clear SGID when inheriting ACLs

2017-10-12T09:27:35+00:00

commit a3bb2d5587521eea6dab2d05326abb0afb460abd upstream.

When new directory 'DIR1' is created in a directory 'DIR0' with SGID bit
set, DIR1 is expected to have SGID bit set (and owning group equal to
the owning group of 'DIR0'). However when 'DIR0' also has some default
ACLs that 'DIR1' inherits, setting these ACLs will result in SGID bit on
'DIR1' to get cleared if user is not member of the owning group.

Fix the problem by moving posix_acl_update_mode() out of
__ext4_set_acl() into ext4_set_acl(). That way the function will not be
called when inheriting ACLs which is what we want as it prevents SGID
bit clearing and the mode has been properly set by posix_acl_create()
anyway.

Fixes: 073931017b49d9458aa351605b43a7e34598caef
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jan Kara 
Reviewed-by: Andreas Gruenbacher 
Signed-off-by: Greg Kroah-Hartman

ext4: fix data corruption for mmap writes

2017-10-12T09:27:35+00:00

commit a056bdaae7a181f7dcc876cfab2f94538e508709 upstream.

mpage_submit_page() can race with another process growing i_size and
writing data via mmap to the written-back page. As mpage_submit_page()
samples i_size too early, it may happen that ext4_bio_write_page()
zeroes out too large tail of the page and thus corrupts user data.

Fix the problem by sampling i_size only after the page has been
write-protected in page tables by clear_page_dirty_for_io() call.

Reported-by: Michael Zimmer 
CC: stable@vger.kernel.org
Fixes: cb20d5188366f04d96d2e07b1240cc92170ade40
Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: fix quota inconsistency during orphan cleanup for read-only mounts

2017-09-27T09:00:14+00:00

commit 95f1fda47c9d8738f858c3861add7bf0a36a7c0b upstream.

Quota does not get enabled for read-only mounts if filesystem
has quota feature, so that quotas cannot updated during orphan
cleanup, which will lead to quota inconsistency.

This patch turn on quotas during orphan cleanup for this case,
make sure quotas can be updated correctly.

Reported-by: Jan Kara 
Signed-off-by: zhangyi (F) 
Signed-off-by: Theodore Ts'o 
Reviewed-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

ext4: fix incorrect quotaoff if the quota feature is enabled

2017-09-27T09:00:14+00:00

commit b0a5a9589decd07db755d6a8d9c0910d96ff7992 upstream.

Current ext4 quota should always "usage enabled" if the
quota feautre is enabled. But in ext4_orphan_cleanup(), it
turn quotas off directly (used for the older journaled
quota), so we cannot turn it on again via "quotaon" unless
umount and remount ext4.

Simple reproduce:

  mkfs.ext4 -O project,quota /dev/vdb1
  mount -o prjquota /dev/vdb1 /mnt
  chattr -p 123 /mnt
  chattr +P /mnt
  touch /mnt/aa /mnt/bb
  exec 100<>/mnt/aa
  rm -f /mnt/aa
  sync
  echo c > /proc/sysrq-trigger

  #reboot and mount
  mount -o prjquota /dev/vdb1 /mnt
  #query status
  quotaon -Ppv /dev/vdb1
  #output
  quotaon: Cannot find mountpoint for device /dev/vdb1
  quotaon: No correct mountpoint specified.

This patch add check for journaled quotas to avoid incorrect
quotaoff when ext4 has quota feautre.

Signed-off-by: zhangyi (F) 
Signed-off-by: Theodore Ts'o 
Reviewed-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman