When using both encryption and SELinux (or another feature that requires
an xattr per file) on a filesystem with 256-byte inodes, each file's
xattrs usually spill into an external xattr block.  Currently, the
xattrs are inherited in the order ACL, security, then encryption.
Therefore, if spillage occurs, the encryption xattr will always end up
in the external block.  This is not ideal because the encryption xattrs
contain a nonce, so they will always be unique and will prevent the
external xattr blocks from being deduplicated.

To improve the situation, change the inheritance order to encryption,
ACL, then security.  This gives the encryption xattr a better chance to
be stored in-inode, allowing the other xattr(s) to be deduplicated.

Note that it may be better for userspace to format the filesystem with
512-byte inodes in this case.  However, it's not the default.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Add #include <linux/cred.h> dependencies to all .c files rely on sched.h
doing that for them.

Note that even if the count where we need to add extra headers seems high,
it's still a net win, because <linux/sched.h> is included in over
2,200 files ...
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Add a shutdown bit that will cause ext4 processing to fail immediately
with EIO.
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

As part of an effort to clean up fscrypt-related error codes, make
attempting to create a file in an encrypted directory that hasn't been
"unlocked" fail with ENOKEY.  Previously, several error codes were used
for this case, including ENOENT, EACCES, and EPERM, and they were not
consistent between and within filesystems.  ENOKEY is a better choice
because it expresses that the failure is due to lacking the encryption
key.  It also matches the error code returned when trying to open an
encrypted regular file without the key.

I am not aware of any users who might be relying on the previous
inconsistent error codes, which were never documented anywhere.

This failure case will be exercised by an xfstest.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

On a lockdep-enabled kernel, xfstests generic/027 fails due to a lockdep
warning when run on ext4 mounted with -o test_dummy_encryption:

    xfs_io/4594 is trying to acquire lock:
     (jbd2_handle
    ){++++.+}, at:
    [<ffffffff813096ef>] jbd2_log_wait_commit+0x5/0x11b

    but task is already holding lock:
     (jbd2_handle
    ){++++.+}, at:
    [<ffffffff813000de>] start_this_handle+0x354/0x3d8

The abbreviated call stack is:

 [<ffffffff813096ef>] ? jbd2_log_wait_commit+0x5/0x11b
 [<ffffffff8130972a>] jbd2_log_wait_commit+0x40/0x11b
 [<ffffffff813096ef>] ? jbd2_log_wait_commit+0x5/0x11b
 [<ffffffff8130987b>] ? __jbd2_journal_force_commit+0x76/0xa6
 [<ffffffff81309896>] __jbd2_journal_force_commit+0x91/0xa6
 [<ffffffff813098b9>] jbd2_journal_force_commit_nested+0xe/0x18
 [<ffffffff812a6049>] ext4_should_retry_alloc+0x72/0x79
 [<ffffffff812f0c1f>] ext4_xattr_set+0xef/0x11f
 [<ffffffff812cc35b>] ext4_set_context+0x3a/0x16b
 [<ffffffff81258123>] fscrypt_inherit_context+0xe3/0x103
 [<ffffffff812ab611>] __ext4_new_inode+0x12dc/0x153a
 [<ffffffff812bd371>] ext4_create+0xb7/0x161

When a file is created in an encrypted directory, ext4_set_context() is
called to set an encryption context on the new file.  This calls
ext4_xattr_set(), which contains a retry loop where the journal is
forced to commit if an ENOSPC error is encountered.

If the task actually were to wait for the journal to commit in this
case, then it would deadlock because a handle remains open from
__ext4_new_inode(), so the running transaction can't be committed yet.
Fortunately, __jbd2_journal_force_commit() avoids the deadlock by not
allowing the running transaction to be committed while the current task
has it open.  However, the above lockdep warning is still triggered.

This was a false positive which was introduced by: 1eaa566d: jbd2:
track more dependencies on transaction commit

Fix the problem by passing the handle through the 'fs_data' argument to
ext4_set_context(), then using ext4_xattr_set_handle() instead of
ext4_xattr_set().  And in the case where no journal handle is specified
and ext4_set_context() has to open one, add an ENOSPC retry loop since
in that case it is the outermost transaction.
Signed-off-by: NEric Biggers <ebiggers@google.com>

CURRENT_TIME_SEC and CURRENT_TIME are not y2038 safe.
current_time() will be transitioned to be y2038 safe
along with vfs.

current_time() returns timestamps according to the
granularities set in the super_block.
The granularity check in ext4_current_time() to call
current_time() or CURRENT_TIME_SEC is not required.
Use current_time() directly to obtain timestamps
unconditionally, and remove ext4_current_time().

Quota files are assumed to be on the same filesystem.
Hence, use current_time() for these files as well.
Signed-off-by: NDeepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>

Use the ext4_{has,set,clear}_feature_* helpers to replace the old
feature helpers.
Signed-off-by: NKaho Ng <ngkaho1234@gmail.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>

This patch removes the most parts of internal crypto codes.
And then, it modifies and adds some ext4-specific crypt codes to use the generic
facility.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

This has submit_bh users pass in the operation and flags separately,
so submit_bh_wbc can setup the bio op and bi_rw flags on the bio that
is submitted.
Signed-off-by: NMike Christie <mchristi@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Instead of just printing warning messages, if the orphan list is
corrupted, declare the file system is corrupted.  If there are any
reserved inodes in the orphaned inode list, declare the file system
corrupted and stop right away to avoid doing more potential damage to
the file system.

Cc: stable@vger.kernel.org
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

If the orphaned inode list contains inode #5, ext4_iget() returns a
bad inode (since the bootloader inode should never be referenced
directly).  Because of the bad inode, we end up processing the inode
repeatedly and this hangs the machine.

This can be reproduced via:

   mke2fs -t ext4 /tmp/foo.img 100
   debugfs -w -R "ssv last_orphan 5" /tmp/foo.img
   mount -o loop /tmp/foo.img /mnt

(But don't do this if you are using an unpatched kernel if you care
about the system staying functional.  :-)

This bug was found by the port of American Fuzzy Lop into the kernel
to find file system problems[1].  (Since it *only* happens if inode #5
shows up on the orphan list --- 3, 7, 8, etc. won't do it, it's not
surprising that AFL needed two hours before it found it.)

[1] http://events.linuxfoundation.org/sites/events/files/slides/AFL%20filesystem%20fuzzing%2C%20Vault%202016_0.pdf

Cc: stable@vger.kernel.org
Reported by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Signed-off-by: NAdam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

When block group checksum is wrong, we call ext4_error() while holding
group spinlock from ext4_init_block_bitmap() or
ext4_init_inode_bitmap() which results in scheduling while in atomic.
Fix the issue by calling ext4_error() later after dropping the spinlock.

CC: stable@vger.kernel.org
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>

Signed-off-by: NLi Xi <lixi@ddn.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NAndreas Dilger <adilger@dilger.ca>
Reviewed-by: NJan Kara <jack@suse.cz>

Make the bitmap reaading routines return real error codes (EIO,
EFSCORRUPTED, EFSBADCRC) which can then be reflected back to
userspace for more precise diagnosis work.

In particular, this means that mballoc no longer claims that we're out
of memory if the block bitmaps become corrupt.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Create separate predicate functions to test/set/clear feature flags,
thereby replacing the wordy old macros.  Furthermore, clean out the
places where we open-coded feature tests.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Instead of overloading EIO for CRC errors and corrupt structures,
return the same error codes that XFS returns for the same issues.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

dquot_initialize() can now return error. Handle it where possible.
Acked-by: NTheodore Ts'o <tytso@mit.edu>
Signed-off-by: NJan Kara <jack@suse.com>

Factor out calls to ext4_inherit_context() and move them to
__ext4_new_inode(); this fixes a problem where ext4_tmpfile() wasn't
calling calling ext4_inherit_context(), so the temporary file wasn't
getting protected.  Since the blocks for the tmpfile could end up on
disk, they really should be protected if the tmpfile is created within
the context of an encrypted directory.
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

The superblock fields s_file_encryption_mode and s_dir_encryption_mode
are vestigal, so remove them as a cleanup.  While we're at it, allow
file systems with both encryption and inline_data enabled at the same
time to work correctly.  We can't have encrypted inodes with inline
data, but there's no reason to prohibit unencrypted inodes from using
the inline data feature.
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Also add the test dummy encryption mode flag so we can more easily
test the encryption patches using xfstests.
Signed-off-by: NMichael Halcrow <mhalcrow@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NUday Savagaonkar <savagaon@google.com>
Signed-off-by: NIldar Muslukhov <ildarm@google.com>
Signed-off-by: NMichael Halcrow <mhalcrow@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Pulls block_write_begin() into fs/ext4/inode.c because it might need
to do a low-level read of the existing data, in which case we need to
decrypt it.
Signed-off-by: NMichael Halcrow <mhalcrow@google.com>
Signed-off-by: NIldar Muslukhov <ildarm@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Remove unused header files and header files which are included in
ext4.h.
Signed-off-by: NSheng Yong <shengyong1@huawei.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

When we fail to load block bitmap in __ext4_new_inode() we will
dereference NULL pointer in ext4_journal_get_write_access(). So check
for error from ext4_read_block_bitmap().

Coverity-id: 989065
Cc: stable@vger.kernel.org
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Besides the fact that this replacement improves code readability
it also protects from errors caused direct EXT4_S(sb)->s_es manipulation
which may result attempt to use uninitialized  csum machinery.

#Testcase_BEGIN
IMG=/dev/ram0
MNT=/mnt
mkfs.ext4 $IMG
mount $IMG $MNT
#Enable feature directly on disk, on mounted fs
tune2fs -O metadata_csum  $IMG
# Provoke metadata update, likey result in OOPS
touch $MNT/test
umount $MNT
#Testcase_END

# Replacement script
@@
expression E;
@@
- EXT4_HAS_RO_COMPAT_FEATURE(E, EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)
+ ext4_has_metadata_csum(E)

https://bugzilla.kernel.org/show_bug.cgi?id=82201Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

Fix potential null pointer dereferencing problem caused by e43bb4e6
("ext4: decrement free clusters/inodes counters when block group declared bad")
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NAshish Sangwan <a.sangwan@samsung.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NLukas Czerner <lczerner@redhat.com>

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: NTheodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

We should decrement free clusters counter when block bitmap is marked
as corrupt and free inodes counter when the allocation bitmap is
marked as corrupt to avoid misunderstanding due to incorrect available
size in statfs result.  User can get immediately ENOSPC error from
write begin without reaching for the writepages.

Cc: Darrick J. Wong<darrick.wong@oracle.com>
Reported-by: NAmit Sahrawat <amit.sahrawat83@gmail.com>
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NAshish Sangwan <a.sangwan@samsung.com>

Many of the uses of get_random_bytes() do not actually need
cryptographically secure random numbers.  Replace those uses with a
call to prandom_u32(), which is faster and which doesn't consume
entropy from the /dev/random driver.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

If the group descriptor fails validation, mark the whole blockgroup
corrupt so that the inode/block allocators skip this group.  The
previous approach takes the risk of writing to a damaged group
descriptor; hopefully it was never the case that the [ib]bitmap fields
pointed to another valid block and got dirtied, since the memset would
fill the page with 1s.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

If we detect either a discrepancy between the inode bitmap and the
inode counts or the inode bitmap fails to pass validation checks, mark
the block group corrupt and refuse to allocate or deallocate inodes
from the group.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

In no journal mode, if an inode has recently been deleted, we
shouldn't reuse it right away.  Otherwise it's possible, after an
unclean shutdown, to hit a situation where a recently deleted inode
gets reused for some other purpose before the inode table block has
been written to disk.  However, if the directory entry has been
updated, then the directory entry will be pointing at the old inode
contents.

E2fsck will make sure the file system is consistent after the
unclean shutdown.  However, if the recently deleted inode is a
character mode device, or an inode with the immutable bit set, even
after the file system has been fixed up by e2fsck, it can be
possible for a *.pyc file to be pointing at a character mode
device, and when python tries to open the *.pyc file, Hilarity
Ensues.  We could change all of userspace to be very suspicious
about stat'ing files before opening them, and clearing the
immutable flag if necessary --- or we can just avoid reusing an
inode number if it has been recently deleted.

Google-Bug-Id: 10017573
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

When we try to allocate an inode, and there is a race between two
CPU's trying to grab the same inode, _and_ this inode is the last free
inode in the block group, make sure the group number is bumped before
we continue searching the rest of the block groups.  Otherwise, we end
up searching the current block group twice, and we end up skipping
searching the last block group.  So in the unlikely situation where
almost all of the inodes are allocated, it's possible that we will
return ENOSPC even though there might be free inodes in that last
block group.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

Reviewed-by: NZheng Liu <wenqing.lz@taobao.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

As Dave Chinner pointed out at the 2013 LSF/MM workshop, it's
important that metadata I/O requests are marked as such to avoid
priority inversions caused by I/O bandwidth throttling.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Inode allocation transaction is pretty heavy (246 credits with quotas
and extents before previous patch, still around 200 after it).  This is
mostly due to credits required for allocation of quota structures
(credits there are heavily overestimated but it's difficult to make
better estimates if we don't want to wire non-trivial assumptions about
quota format into filesystem).

So move quota initialization out of allocation transaction. That way
transaction for quota structure allocation will be started only if we
need to look up quota structure on disk (rare) and furthermore it will
be started for each quota type separately, not for all of them at once.
This reduces maximum transaction size to 34 is most cases and to 73 in
the worst case.

[ Modified by tytso to clean up the cleanup paths for error handling.
  Also use a separate call to ext4_std_error() for each failure so it
  is easier for someone who is debugging a problem in this function to
  determine which function call failed. ]
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

This patch should fix sparse complains about shadow declatations.
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

A user who was using a 8TB+ file system and with a very large flexbg
size (> 65536) could cause the atomic_t used in the struct flex_groups
to overflow.  This was detected by PaX security patchset:

http://forums.grsecurity.net/viewtopic.php?f=3&t=3289&p=12551#p12551

This bug was introduced in commit 9f24e420, so it's been around
since 2.6.30.  :-(

Fix this by using an atomic64_t for struct orlav_stats's
free_clusters.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: NLukas Czerner <lczerner@redhat.com>
Cc: stable@vger.kernel.org