commit 9d5afec6b8bd46d6ed821aa1579634437f58ef1f upstream.
On a ppc64 machine, when mounting a fuzzed ext2 image (generated by
fsfuzzer) the following call trace is seen,
VFS: brelse: Trying to free free buffer
WARNING: CPU: 1 PID: 6913 at /root/repos/linux/fs/buffer.c:1165 .__brelse.part.6+0x24/0x40
.__brelse.part.6+0x20/0x40 (unreliable)
.ext4_find_entry+0x384/0x4f0
.ext4_lookup+0x84/0x250
.lookup_slow+0xdc/0x230
.walk_component+0x268/0x400
.path_lookupat+0xec/0x2d0
.filename_lookup+0x9c/0x1d0
.vfs_statx+0x98/0x140
.SyS_newfstatat+0x48/0x80
system_call+0x58/0x6c
This happens because the directory that ext4_find_entry() looks up has
inode->i_size that is less than the block size of the filesystem. This
causes 'nblocks' to have a value of zero. ext4_bread_batch() ends up not
reading any of the directory file's blocks. This renders the entries in
bh_use[] array to continue to have garbage data. buffer_uptodate() on
bh_use[0] can then return a zero value upon which brelse() function is
invoked.
This commit fixes the bug by returning -ENOENT when the directory file
has no associated blocks.
Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c894aa97577e47d3066b27b32499ecf899bfa8b0 upstream.
Currently, fallocate(2) with KEEP_SIZE followed by a fdatasync(2)
then crash, we'll see wrong allocated block number (stat -c %b), the
blocks allocated beyond EOF are all lost. fstests generic/468
exposes this bug.
Commit 67a7d5f561f4 ("ext4: fix fdatasync(2) after extent
manipulation operations") fixed all the other extent manipulation
operation paths such as hole punch, zero range, collapse range etc.,
but forgot the fallocate case.
So similarly, fix it by recording the correct journal tid in ext4
inode in fallocate(2) path, so that ext4_sync_file() will wait for
the right tid to be committed on fdatasync(2).
This addresses the test failure in xfstests test generic/468.
Signed-off-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a0b3bc855374c50b5ea85273553485af48caf2f7 upstream.
fscrypt_initialize(), which allocates the global bounce page pool when
an encrypted file is first accessed, uses "double-checked locking" to
try to avoid locking fscrypt_init_mutex. However, it doesn't use any
memory barriers, so it's theoretically possible for a thread to observe
a bounce page pool which has not been fully initialized. This is a
classic bug with "double-checked locking".
While "only a theoretical issue" in the latest kernel, in pre-4.8
kernels the pointer that was checked was not even the last to be
initialized, so it was easily possible for a crash (NULL pointer
dereference) to happen. This was changed only incidentally by the large
refactor to use fs/crypto/.
Solve both problems in a trivial way that can easily be backported: just
always take the mutex. It's theoretically less efficient, but it
shouldn't be noticeable in practice as the mutex is only acquired very
briefly once per encrypted file.
Later I'd like to make this use a helper macro like DO_ONCE(). However,
DO_ONCE() runs in atomic context, so we'd need to add a new macro that
allows blocking.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 51e3ae81ec58e95f10a98ef3dd6d7bce5d8e35a2 upstream.
If there are pending writes subject to delayed allocation, then i_size
will show size after the writes have completed, while i_disksize
contains the value of i_size on the disk (since the writes have not
been persisted to disk).
If fallocate(2) is called with the FALLOC_FL_KEEP_SIZE flag, either
with or without the FALLOC_FL_ZERO_RANGE flag set, and the new size
after the fallocate(2) is between i_size and i_disksize, then after a
crash, if a journal commit has resulted in the changes made by the
fallocate() call to be persisted after a crash, but the delayed
allocation write has not resolved itself, i_size would not be updated,
and this would cause the following e2fsck complaint:
Inode 12, end of extent exceeds allowed value
(logical block 33, physical block 33441, len 7)
This can only take place on a sparse file, where the fallocate(2) call
is allocating blocks in a range which is before a pending delayed
allocation write which is extending i_size. Since this situation is
quite rare, and the window in which the crash must take place is
typically < 30 seconds, in practice this condition will rarely happen.
Nevertheless, it can be triggered in testing, and in particular by
xfstests generic/456.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 f3b59291a6 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: f3b59291a6
Reported-by: "HUANG Weller (CM/ESW12-CN)" <Weller.Huang@cn.bosch.com>
Tested-by: "HUANG Weller (CM/ESW12-CN)" <Weller.Huang@cn.bosch.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
[bwh: Backported to 4.4:
- Drop check for EXT4_GET_BLOCKS_ZERO flag
- Adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ 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 <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d9b22cf9f5466a057f2a4f1e642b469fa9d73117 ]
When a filesystem is created using:
mkfs.ext4 -b 4096 -E stride=512 <dev>
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 <ross.zwisler@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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: 88bd6ccdcd ("ext4 crypto: add encryption key management facilities")
Reviewed-by: James Morris <james.l.morris@oracle.com>
Cc: <stable@vger.kernel.org> [v4.1+]
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 <muttdini@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 <michael@swarm64.com>
CC: stable@vger.kernel.org
Fixes: cb20d51883
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 <jack@suse.cz>
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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) <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit aec51758ce10a9c847a62a48a168f8c804c6e053 upstream.
On a 32-bit platform, the value of n_blcoks_count may be wrong during
the file system is resized to size larger than 2^32 blocks. This may
caused the superblock being corrupted with zero blocks count.
Fixes: 1c6bd7173d
Signed-off-by: Jerry Lee <jerrylee@qnap.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fcf5ea10992fbac3c7473a1db33d56a139333cd1 upstream.
ext4_find_unwritten_pgoff() does not properly handle a situation when
starting index is in the middle of a page and blocksize < pagesize. The
following command shows the bug on filesystem with 1k blocksize:
xfs_io -f -c "falloc 0 4k" \
-c "pwrite 1k 1k" \
-c "pwrite 3k 1k" \
-c "seek -a -r 0" foo
In this example, neither lseek(fd, 1024, SEEK_HOLE) nor lseek(fd, 2048,
SEEK_DATA) will return the correct result.
Fix the problem by neglecting buffers in a page before starting offset.
Reported-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1ea1516fbbab2b30bf98c534ecaacba579a35208 upstream.
kstrtoull returns 0 on success, however, in reserved_clusters_store we
will return -EINVAL if kstrtoull returns 0, it makes us fail to update
reserved_clusters value through sysfs.
Fixes: 76d33bca55
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 93407472a21b82f39c955ea7787e5bc7da100642 upstream.
Replace all 1 << inode->i_blkbits and (1 << inode->i_blkbits) in fs
branch.
This patch also fixes multiple checkpatch warnings: WARNING: Prefer
'unsigned int' to bare use of 'unsigned'
Thanks to Andrew Morton for suggesting more appropriate function instead
of macro.
[geliangtang@gmail.com: truncate: use i_blocksize()]
Link: http://lkml.kernel.org/r/9c8b2cd83c8f5653805d43debde9fa8817e02fc4.1484895804.git.geliangtang@gmail.com
Link: http://lkml.kernel.org/r/1481319905-10126-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 67a7d5f561f469ad2fa5154d2888258ab8e6df7c upstream.
Currently, extent manipulation operations such as hole punch, range
zeroing, or extent shifting do not record the fact that file data has
changed and thus fdatasync(2) has a work to do. As a result if we crash
e.g. after a punch hole and fdatasync, user can still possibly see the
punched out data after journal replay. Test generic/392 fails due to
these problems.
Fix the problem by properly marking that file data has changed in these
operations.
Fixes: a4bb6b64e3
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 887a9730614727c4fff7cb756711b190593fc1df upstream.
ext4_expand_extra_isize() should clear only space between old and new
size.
Fixes: 6dd4ee7cab # v2.6.23
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7d95eddf313c88b24f99d4ca9c2411a4b82fef33 upstream.
Currently, SEEK_HOLE implementation in ext4 may both return that there's
a hole at some offset although that offset already has data and skip
some holes during a search for the next hole. The first problem is
demostrated by:
xfs_io -c "falloc 0 256k" -c "pwrite 0 56k" -c "seek -h 0" file
wrote 57344/57344 bytes at offset 0
56 KiB, 14 ops; 0.0000 sec (2.054 GiB/sec and 538461.5385 ops/sec)
Whence Result
HOLE 0
Where we can see that SEEK_HOLE wrongly returned offset 0 as containing
a hole although we have written data there. The second problem can be
demonstrated by:
xfs_io -c "falloc 0 256k" -c "pwrite 0 56k" -c "pwrite 128k 8k"
-c "seek -h 0" file
wrote 57344/57344 bytes at offset 0
56 KiB, 14 ops; 0.0000 sec (1.978 GiB/sec and 518518.5185 ops/sec)
wrote 8192/8192 bytes at offset 131072
8 KiB, 2 ops; 0.0000 sec (2 GiB/sec and 500000.0000 ops/sec)
Whence Result
HOLE 139264
Where we can see that hole at offsets 56k..128k has been ignored by the
SEEK_HOLE call.
The underlying problem is in the ext4_find_unwritten_pgoff() which is
just buggy. In some cases it fails to update returned offset when it
finds a hole (when no pages are found or when the first found page has
higher index than expected), in some cases conditions for detecting hole
are just missing (we fail to detect a situation where indices of
returned pages are not contiguous).
Fix ext4_find_unwritten_pgoff() to properly detect non-contiguous page
indices and also handle all cases where we got less pages then expected
in one place and handle it properly there.
Fixes: c8c0df241c
CC: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6b06cdee81d68a8a829ad8e8d0f31d6836744af9 upstream.
When accessing an encrypted directory without the key, userspace must
operate on filenames derived from the ciphertext names, which contain
arbitrary bytes. Since we must support filenames as long as NAME_MAX,
we can't always just base64-encode the ciphertext, since that may make
it too long. Currently, this is solved by presenting long names in an
abbreviated form containing any needed filesystem-specific hashes (e.g.
to identify a directory block), then the last 16 bytes of ciphertext.
This needs to be sufficient to identify the actual name on lookup.
However, there is a bug. It seems to have been assumed that due to the
use of a CBC (ciphertext block chaining)-based encryption mode, the last
16 bytes (i.e. the AES block size) of ciphertext would depend on the
full plaintext, preventing collisions. However, we actually use CBC
with ciphertext stealing (CTS), which handles the last two blocks
specially, causing them to appear "flipped". Thus, it's actually the
second-to-last block which depends on the full plaintext.
This caused long filenames that differ only near the end of their
plaintexts to, when observed without the key, point to the wrong inode
and be undeletable. For example, with ext4:
# echo pass | e4crypt add_key -p 16 edir/
# seq -f "edir/abcdefghijklmnopqrstuvwxyz012345%.0f" 100000 | xargs touch
# find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l
100000
# sync
# echo 3 > /proc/sys/vm/drop_caches
# keyctl new_session
# find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l
2004
# rm -rf edir/
rm: cannot remove 'edir/_A7nNFi3rhkEQlJ6P,hdzluhODKOeWx5V': Structure needs cleaning
...
To fix this, when presenting long encrypted filenames, encode the
second-to-last block of ciphertext rather than the last 16 bytes.
Although it would be nice to solve this without depending on a specific
encryption mode, that would mean doing a cryptographic hash like SHA-256
which would be much less efficient. This way is sufficient for now, and
it's still compatible with encryption modes like HEH which are strong
pseudorandom permutations. Also, changing the presented names is still
allowed at any time because they are only provided to allow applications
to do things like delete encrypted directories. They're not designed to
be used to persistently identify files --- which would be hard to do
anyway, given that they're encrypted after all.
For ease of backports, this patch only makes the minimal fix to both
ext4 and f2fs. It leaves ubifs as-is, since ubifs doesn't compare the
ciphertext block yet. Follow-on patches will clean things up properly
and make the filesystems use a shared helper function.
Fixes: 5de0b4d0cd ("ext4 crypto: simplify and speed up filename encryption")
Reported-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 272f98f6846277378e1758a49a49d7bf39343c02 upstream.
To mitigate some types of offline attacks, filesystem encryption is
designed to enforce that all files in an encrypted directory tree use
the same encryption policy (i.e. the same encryption context excluding
the nonce). However, the fscrypt_has_permitted_context() function which
enforces this relies on comparing struct fscrypt_info's, which are only
available when we have the encryption keys. This can cause two
incorrect behaviors:
1. If we have the parent directory's key but not the child's key, or
vice versa, then fscrypt_has_permitted_context() returned false,
causing applications to see EPERM or ENOKEY. This is incorrect if
the encryption contexts are in fact consistent. Although we'd
normally have either both keys or neither key in that case since the
master_key_descriptors would be the same, this is not guaranteed
because keys can be added or removed from keyrings at any time.
2. If we have neither the parent's key nor the child's key, then
fscrypt_has_permitted_context() returned true, causing applications
to see no error (or else an error for some other reason). This is
incorrect if the encryption contexts are in fact inconsistent, since
in that case we should deny access.
To fix this, retrieve and compare the fscrypt_contexts if we are unable
to set up both fscrypt_infos.
While this slightly hurts performance when accessing an encrypted
directory tree without the key, this isn't a case we really need to be
optimizing for; access *with* the key is much more important.
Furthermore, the performance hit is barely noticeable given that we are
already retrieving the fscrypt_context and doing two keyring searches in
fscrypt_get_encryption_info(). If we ever actually wanted to optimize
this case we might start by caching the fscrypt_contexts.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4762cc3fbbd89e5fd316d6e4d3244a8984444f8d upstream.
We should be testing for -ENOMEM but the minus sign is missing.
Fixes: c9af28fdd449 ('ext4 crypto: don't let data integrity writebacks fail with ENOMEM')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c9af28fdd44922a6c10c9f8315718408af98e315 upstream.
We don't want the writeback triggered from the journal commit (in
data=writeback mode) to cause the journal to abort due to
generic_writepages() returning an ENOMEM error. In addition, if
fsync() fails with ENOMEM, most applications will probably not do the
right thing.
So if we are doing a data integrity sync, and ext4_encrypt() returns
ENOMEM, we will submit any queued I/O to date, and then retry the
allocation using GFP_NOFAIL.
Google-Bug-Id: 27641567
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7b4cc9787fe35b3ee2dfb1c35e22eafc32e00c33 upstream.
Currently the case of writing via mmap to a file with inline data is not
handled. This is maybe a rare case since it requires a writable memory
map of a very small file, but it is trivial to trigger with on
inline_data filesystem, and it causes the
'BUG_ON(ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA));' in
ext4_writepages() to be hit:
mkfs.ext4 -O inline_data /dev/vdb
mount /dev/vdb /mnt
xfs_io -f /mnt/file \
-c 'pwrite 0 1' \
-c 'mmap -w 0 1m' \
-c 'mwrite 0 1' \
-c 'fsync'
kernel BUG at fs/ext4/inode.c:2723!
invalid opcode: 0000 [#1] SMP
CPU: 1 PID: 2532 Comm: xfs_io Not tainted 4.11.0-rc1-xfstests-00301-g071d9acf3d1f #633
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-20170228_101828-anatol 04/01/2014
task: ffff88003d3a8040 task.stack: ffffc90000300000
RIP: 0010:ext4_writepages+0xc89/0xf8a
RSP: 0018:ffffc90000303ca0 EFLAGS: 00010283
RAX: 0000028410000000 RBX: ffff8800383fa3b0 RCX: ffffffff812afcdc
RDX: 00000a9d00000246 RSI: ffffffff81e660e0 RDI: 0000000000000246
RBP: ffffc90000303dc0 R08: 0000000000000002 R09: 869618e8f99b4fa5
R10: 00000000852287a2 R11: 00000000a03b49f4 R12: ffff88003808e698
R13: 0000000000000000 R14: 7fffffffffffffff R15: 7fffffffffffffff
FS: 00007fd3e53094c0(0000) GS:ffff88003e400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd3e4c51000 CR3: 000000003d554000 CR4: 00000000003406e0
Call Trace:
? _raw_spin_unlock+0x27/0x2a
? kvm_clock_read+0x1e/0x20
do_writepages+0x23/0x2c
? do_writepages+0x23/0x2c
__filemap_fdatawrite_range+0x80/0x87
filemap_write_and_wait_range+0x67/0x8c
ext4_sync_file+0x20e/0x472
vfs_fsync_range+0x8e/0x9f
? syscall_trace_enter+0x25b/0x2d0
vfs_fsync+0x1c/0x1e
do_fsync+0x31/0x4a
SyS_fsync+0x10/0x14
do_syscall_64+0x69/0x131
entry_SYSCALL64_slow_path+0x25/0x25
We could try to be smart and keep the inline data in this case, or at
least support delayed allocation when allocating the block, but these
solutions would be more complicated and don't seem worthwhile given how
rare this case seems to be. So just fix the bug by calling
ext4_convert_inline_data() when we're asked to make a page writable, so
that any inline data gets evicted, with the block allocated immediately.
Reported-by: Nick Alcock <nick.alcock@oracle.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 03a8bb0e53d9562276045bdfcf2b5de2e4cff5a1 upstream.
As Al pointed, d_revalidate should return RCU lookup before using d_inode.
This was originally introduced by:
commit 34286d6662 ("fs: rcu-walk aware d_revalidate method").
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3d43bcfef5f0548845a425365011c499875491b0 upstream.
This avoids potential problems caused by a race where the inode gets
renamed out from its parent directory and the parent directory is
deleted while ext4_d_revalidate() is running.
Fixes: 28b4c263961c
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 28b4c263961c47da84ed8b5be0b5116bad1133eb upstream.
Add a validation check for dentries for encrypted directory to make
sure we're not caching stale data after a key has been added or removed.
Also check to make sure that status of the encryption key is updated
when readdir(2) is executed.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9a200d075e5d05be1fcad4547a0f8aee4e2f9a04 upstream.
...otherwise an user can enable encryption for certain files even
when the filesystem is unable to support it.
Such a case would be a filesystem created by mkfs.ext4's default
settings, 1KiB block size. Ext4 supports encyption only when block size
is equal to PAGE_SIZE.
But this constraint is only checked when the encryption feature flag
is set.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9e92f48c34eb2b9af9d12f892e2fe1fce5e8ce35 upstream.
We aren't checking to see if the in-inode extended attribute is
corrupted before we try to expand the inode's extra isize fields.
This can lead to potential crashes caused by the BUG_ON() check in
ext4_xattr_shift_entries().
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 05ac5aa18abd7db341e54df4ae2b4c98ea0e43b7 upstream.
We've fixed the race condition problem in calculating ext4 checksum
value in commit b47820edd163 ("ext4: avoid modifying checksum fields
directly during checksum veficationon"). However, by this change,
when calculating the checksum value of inode whose i_extra_size is
less than 4, we couldn't calculate the checksum value in a proper way.
This problem was found and reported by Nix, Thank you.
Reported-by: Nix <nix@esperi.org.uk>
Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Signed-off-by: Youngjin Gil <youngjin.gil@samsung.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1b53cf9815bb4744958d41f3795d5d5a1d365e2d upstream.
Filesystem encryption ostensibly supported revoking a keyring key that
had been used to "unlock" encrypted files, causing those files to become
"locked" again. This was, however, buggy for several reasons, the most
severe of which was that when key revocation happened to be detected for
an inode, its fscrypt_info was immediately freed, even while other
threads could be using it for encryption or decryption concurrently.
This could be exploited to crash the kernel or worse.
This patch fixes the use-after-free by removing the code which detects
the keyring key having been revoked, invalidated, or expired. Instead,
an encrypted inode that is "unlocked" now simply remains unlocked until
it is evicted from memory. Note that this is no worse than the case for
block device-level encryption, e.g. dm-crypt, and it still remains
possible for a privileged user to evict unused pages, inodes, and
dentries by running 'sync; echo 3 > /proc/sys/vm/drop_caches', or by
simply unmounting the filesystem. In fact, one of those actions was
already needed anyway for key revocation to work even somewhat sanely.
This change is not expected to break any applications.
In the future I'd like to implement a real API for fscrypt key
revocation that interacts sanely with ongoing filesystem operations ---
waiting for existing operations to complete and blocking new operations,
and invalidating and sanitizing key material and plaintext from the VFS
caches. But this is a hard problem, and for now this bug must be fixed.
This bug affected almost all versions of ext4, f2fs, and ubifs
encryption, and it was potentially reachable in any kernel configured
with encryption support (CONFIG_EXT4_ENCRYPTION=y,
CONFIG_EXT4_FS_ENCRYPTION=y, CONFIG_F2FS_FS_ENCRYPTION=y, or
CONFIG_UBIFS_FS_ENCRYPTION=y). Note that older kernels did not use the
shared fs/crypto/ code, but due to the potential security implications
of this bug, it may still be worthwhile to backport this fix to them.
Fixes: b7236e21d5 ("ext4 crypto: reorganize how we store keys in the inode")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b9cf625d6ecde0d372e23ae022feead72b4228a6 upstream.
If ext4_convert_inline_data() was called on a directory with inline
data, the filesystem was left in an inconsistent state (as considered by
e2fsck) because the file size was not increased to cover the new block.
This happened because the inode was not marked dirty after i_disksize
was updated. Fix this by marking the inode dirty at the end of
ext4_finish_convert_inline_dir().
This bug was probably not noticed before because most users mark the
inode dirty afterwards for other reasons. But if userspace executed
FS_IOC_SET_ENCRYPTION_POLICY with invalid parameters, as exercised by
'kvm-xfstests -c adv generic/396', then the inode was never marked dirty
after updating i_disksize.
Fixes: 3c47d54170
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2ba3e6e8afc9b6188b471f27cf2b5e3cf34e7af2 upstream.
It is OK for s_first_meta_bg to be equal to the number of block group
descriptor blocks. (It rarely happens, but it shouldn't cause any
problems.)
https://bugzilla.kernel.org/show_bug.cgi?id=194567
Fixes: 3a4b77cd47bb837b8557595ec7425f281f2ca1fe
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8906a8223ad4909b391c5628f7991ebceda30e52 upstream.
i_rwsem needs to be acquired while setting an encryption policy so that
concurrent calls to FS_IOC_SET_ENCRYPTION_POLICY are correctly
serialized (especially the ->get_context() + ->set_context() pair), and
so that new files cannot be created in the directory during or after the
->empty_dir() check.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Richard Weinberger <richard@nod.at>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 42d97eb0ade31e1bc537d086842f5d6e766d9d51 upstream.
Attempting to link a device node, named pipe, or socket file into an
encrypted directory through rename(2) or link(2) always failed with
EPERM. This happened because fscrypt_has_permitted_context() saw that
the file was unencrypted and forbid creating the link. This behavior
was unexpected because such files are never encrypted; only regular
files, directories, and symlinks can be encrypted.
To fix this, make fscrypt_has_permitted_context() always return true on
special files.
This will be covered by a test in my encryption xfstests patchset.
Fixes: 9bd8212f98 ("ext4 crypto: add encryption policy and password salt support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0d06863f903ac5f4f6efb0273079d27de3e53a28 upstream.
Fix a BUG when the kernel tries to mount a file system constructed as
follows:
echo foo > foo.txt
mke2fs -Fq -t ext4 -O encrypt foo.img 100
debugfs -w foo.img << EOF
write foo.txt a
set_inode_field a i_flags 0x80800
set_super_value s_last_orphan 12
quit
EOF
root@kvm-xfstests:~# mount -o loop foo.img /mnt
[ 160.238770] ------------[ cut here ]------------
[ 160.240106] kernel BUG at /usr/projects/linux/ext4/fs/ext4/inode.c:3874!
[ 160.240106] invalid opcode: 0000 [#1] SMP
[ 160.240106] Modules linked in:
[ 160.240106] CPU: 0 PID: 2547 Comm: mount Tainted: G W 4.10.0-rc3-00034-gcdd33b941b67 #227
[ 160.240106] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1 04/01/2014
[ 160.240106] task: f4518000 task.stack: f47b6000
[ 160.240106] EIP: ext4_block_zero_page_range+0x1a7/0x2b4
[ 160.240106] EFLAGS: 00010246 CPU: 0
[ 160.240106] EAX: 00000001 EBX: f7be4b50 ECX: f47b7dc0 EDX: 00000007
[ 160.240106] ESI: f43b05a8 EDI: f43babec EBP: f47b7dd0 ESP: f47b7dac
[ 160.240106] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
[ 160.240106] CR0: 80050033 CR2: bfd85b08 CR3: 34a00680 CR4: 000006f0
[ 160.240106] Call Trace:
[ 160.240106] ext4_truncate+0x1e9/0x3e5
[ 160.240106] ext4_fill_super+0x286f/0x2b1e
[ 160.240106] ? set_blocksize+0x2e/0x7e
[ 160.240106] mount_bdev+0x114/0x15f
[ 160.240106] ext4_mount+0x15/0x17
[ 160.240106] ? ext4_calculate_overhead+0x39d/0x39d
[ 160.240106] mount_fs+0x58/0x115
[ 160.240106] vfs_kern_mount+0x4b/0xae
[ 160.240106] do_mount+0x671/0x8c3
[ 160.240106] ? _copy_from_user+0x70/0x83
[ 160.240106] ? strndup_user+0x31/0x46
[ 160.240106] SyS_mount+0x57/0x7b
[ 160.240106] do_int80_syscall_32+0x4f/0x61
[ 160.240106] entry_INT80_32+0x2f/0x2f
[ 160.240106] EIP: 0xb76b919e
[ 160.240106] EFLAGS: 00000246 CPU: 0
[ 160.240106] EAX: ffffffda EBX: 08053838 ECX: 08052188 EDX: 080537e8
[ 160.240106] ESI: c0ed0000 EDI: 00000000 EBP: 080537e8 ESP: bfa13660
[ 160.240106] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b
[ 160.240106] Code: 59 8b 00 a8 01 0f 84 09 01 00 00 8b 07 66 25 00 f0 66 3d 00 80 75 61 89 f8 e8 3e e2 ff ff 84 c0 74 56 83 bf 48 02 00 00 00 75 02 <0f> 0b 81 7d e8 00 10 00 00 74 02 0f 0b 8b 43 04 8b 53 08 31 c9
[ 160.240106] EIP: ext4_block_zero_page_range+0x1a7/0x2b4 SS:ESP: 0068:f47b7dac
[ 160.317241] ---[ end trace d6a773a375c810a5 ]---
The problem is that when the kernel tries to truncate an inode in
ext4_truncate(), it tries to clear any on-disk data beyond i_size.
Without the encryption key, it can't do that, and so it triggers a
BUG.
E2fsck does *not* provide this service, and in practice most file
systems have their orphan list processed by e2fsck, so to avoid
crashing, this patch skips this step if we don't have access to the
encryption key (which is the case when processing the orphan list; in
all other cases, we will have the encryption key, or the kernel
wouldn't have allowed the file to be opened).
An open question is whether the fact that e2fsck isn't clearing the
bytes beyond i_size causing problems --- and if we've lived with it
not doing it for so long, can we drop this from the kernel replay of
the orphan list in all cases (not just when we don't have the key for
encrypted inodes).
Addresses-Google-Bug: #35209576
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4753d8a24d4588657bc0a4cd66d4e282dff15c8c upstream.
If the file system requires journal recovery, and the device is
read-ony, return EROFS to the mount system call. This allows xfstests
generic/050 to pass.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 97abd7d4b5d9c48ec15c425485f054e1c15e591b upstream.
If the journal is aborted, the needs_recovery feature flag should not
be removed. Otherwise, it's the journal might not get replayed and
this could lead to more data getting lost.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit eb5efbcb762aee4b454b04f7115f73ccbcf8f0ef upstream.
The write_end() function must always unlock the page and drop its ref
count, even on an error.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3b136499e906460919f0d21a49db1aaccf0ae963 upstream.
ext4_journalled_write_end() did not propely handle all the cases when
generic_perform_write() did not copy all the data into the target page
and could mark buffers with uninitialized contents as uptodate and dirty
leading to possible data corruption (which would be quickly fixed by
generic_perform_write() retrying the write but still). Fix the problem
by carefully handling the case when the page that is written to is not
uptodate.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cd648b8a8fd5071d232242d5ee7ee3c0815776af upstream.
If filesystem groups are artifically small (using parameter -g to
mkfs.ext4), ext4_mb_normalize_request() can result in a request that is
larger than a block group. Trim the request size to not confuse
allocation code.
Reported-by: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 03e916fa8b5577d85471452a3d0c5738aa658dae upstream.
Inside ext4_ext_shift_extents() function ext4_find_extent() is called
without EXT4_EX_NOCACHE flag, which should prevent cache population.
This leads to oudated offsets in the extents tree and wrong blocks
afterwards.
Patch fixes the problem providing EXT4_EX_NOCACHE flag for each
ext4_find_extents() call inside ext4_ext_shift_extents function.
Fixes: 331573febb
Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2a9b8cba62c0741109c33a2be700ff3d7703a7c2 upstream.
While doing 'insert range' start block should be also shifted right.
The bug can be easily reproduced by the following test:
ptr = malloc(4096);
assert(ptr);
fd = open("./ext4.file", O_CREAT | O_TRUNC | O_RDWR, 0600);
assert(fd >= 0);
rc = fallocate(fd, 0, 0, 8192);
assert(rc == 0);
for (i = 0; i < 2048; i++)
*((unsigned short *)ptr + i) = 0xbeef;
rc = pwrite(fd, ptr, 4096, 0);
assert(rc == 4096);
rc = pwrite(fd, ptr, 4096, 4096);
assert(rc == 4096);
for (block = 2; block < 1000; block++) {
rc = fallocate(fd, FALLOC_FL_INSERT_RANGE, 4096, 4096);
assert(rc == 0);
for (i = 0; i < 2048; i++)
*((unsigned short *)ptr + i) = block;
rc = pwrite(fd, ptr, 4096, 4096);
assert(rc == 4096);
}
Because start block is not included in the range the hole appears at
the wrong offset (just after the desired offset) and the following
pwrite() overwrites already existent block, keeping hole untouched.
Simple way to verify wrong behaviour is to check zeroed blocks after
the test:
$ hexdump ./ext4.file | grep '0000 0000'
The root cause of the bug is a wrong range (start, stop], where start
should be inclusive, i.e. [start, stop].
This patch fixes the problem by including start into the range. But
not to break left shift (range collapse) stop points to the beginning
of the a block, not to the end.
The other not obvious change is an iterator check on validness in a
main loop. Because iterator is unsigned the following corner case
should be considered with care: insert a block at 0 offset, when stop
variables overflows and never becomes less than start, which is 0.
To handle this special case iterator is set to NULL to indicate that
end of the loop is reached.
Fixes: 331573febb
Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3a4b77cd47bb837b8557595ec7425f281f2ca1fe upstream.
Ralf Spenneberg reported that he hit a kernel crash when mounting a
modified ext4 image. And it turns out that kernel crashed when
calculating fs overhead (ext4_calculate_overhead()), this is because
the image has very large s_first_meta_bg (debug code shows it's
842150400), and ext4 overruns the memory in count_overhead() when
setting bitmap buffer, which is PAGE_SIZE.
ext4_calculate_overhead():
buf = get_zeroed_page(GFP_NOFS); <=== PAGE_SIZE buffer
blks = count_overhead(sb, i, buf);
count_overhead():
for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) { <=== j = 842150400
ext4_set_bit(EXT4_B2C(sbi, s++), buf); <=== buffer overrun
count++;
}
This can be reproduced easily for me by this script:
#!/bin/bash
rm -f fs.img
mkdir -p /mnt/ext4
fallocate -l 16M fs.img
mke2fs -t ext4 -O bigalloc,meta_bg,^resize_inode -F fs.img
debugfs -w -R "ssv first_meta_bg 842150400" fs.img
mount -o loop fs.img /mnt/ext4
Fix it by validating s_first_meta_bg first at mount time, and
refusing to mount if its value exceeds the largest possible meta_bg
number.
Reported-by: Ralf Spenneberg <ralf@os-t.de>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 73b92a2a5e97d17cc4d5c4fe9d724d3273fb6fd2 upstream.
Currently data journalling is incompatible with encryption: enabling both
at the same time has never been supported by design, and would result in
unpredictable behavior. However, users are not precluded from turning on
both features simultaneously. This change programmatically replaces data
journaling for encrypted regular files with ordered data journaling mode.
Background:
Journaling encrypted data has not been supported because it operates on
buffer heads of the page in the page cache. Namely, when the commit
happens, which could be up to five seconds after caching, the commit
thread uses the buffer heads attached to the page to copy the contents of
the page to the journal. With encryption, it would have been required to
keep the bounce buffer with ciphertext for up to the aforementioned five
seconds, since the page cache can only hold plaintext and could not be
used for journaling. Alternatively, it would be required to setup the
journal to initiate a callback at the commit time to perform deferred
encryption - in this case, not only would the data have to be written
twice, but it would also have to be encrypted twice. This level of
complexity was not justified for a mode that in practice is very rarely
used because of the overhead from the data journalling.
Solution:
If data=journaled has been set as a mount option for a filesystem, or if
journaling is enabled on a regular file, do not perform journaling if the
file is also encrypted, instead fall back to the data=ordered mode for the
file.
Rationale:
The intent is to allow seamless and proper filesystem operation when
journaling and encryption have both been enabled, and have these two
conflicting features gracefully resolved by the filesystem.
Fixes: 4461471107
Signed-off-by: Sergey Karamov <skaramov@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 578620f451f836389424833f1454eeeb2ffc9e9f upstream.
We should set the error code if kzalloc() fails.
Fixes: 67cf5b09a4 ("ext4: add the basic function for inline data support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7e6e1ef48fc02f3ac5d0edecbb0c6087cd758d58 upstream.
Don't load an inode with a negative size; this causes integer overflow
problems in the VFS.
[ Added EXT4_ERROR_INODE() to mark file system as corrupted. -TYT]
Fixes: a48380f769 (ext4: rename i_dir_acl to i_size_high)
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c48ae41bafe31e9a66d8be2ced4e42a6b57fa814 upstream.
The commit "ext4: sanity check the block and cluster size at mount
time" should prevent any problems, but in case the superblock is
modified while the file system is mounted, add an extra safety check
to make sure we won't overrun the allocated buffer.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
