Commit Graph

378 Commits

Author SHA1 Message Date
Daniel Rosenberg
1ae98e295f ext4: optimize match for casefolded encrypted dirs
Matching names with casefolded encrypting directories requires
decrypting entries to confirm case since we are case preserving. We can
avoid needing to decrypt if our hash values don't match.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Link: https://lore.kernel.org/r/20210319073414.1381041-3-drosen@google.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-04-05 22:18:36 -04:00
Daniel Rosenberg
471fbbea7f ext4: handle casefolding with encryption
This adds support for encryption with casefolding.

Since the name on disk is case preserving, and also encrypted, we can no
longer just recompute the hash on the fly. Additionally, to avoid
leaking extra information from the hash of the unencrypted name, we use
siphash via an fscrypt v2 policy.

The hash is stored at the end of the directory entry for all entries
inside of an encrypted and casefolded directory apart from those that
deal with '.' and '..'. This way, the change is backwards compatible
with existing ext4 filesystems.

[ Changed to advertise this feature via the file:
  /sys/fs/ext4/features/encrypted_casefold -- TYT ]

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20210319073414.1381041-2-drosen@google.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-04-05 22:04:20 -04:00
Harshad Shirwadkar
8210bb29c1 ext4: fix rename whiteout with fast commit
This patch adds rename whiteout support in fast commits. Note that the
whiteout object that gets created is actually char device. Which
imples, the function ext4_inode_journal_mode(struct inode *inode)
would return "JOURNAL_DATA" for this inode. This has a consequence in
fast commit code that it will make creation of the whiteout object a
fast-commit ineligible behavior and thus will fall back to full
commits. With this patch, this can be observed by running fast commits
with rename whiteout and seeing the stats generated by ext4_fc_stats
tracepoint as follows:

ext4_fc_stats: dev 254:32 fc ineligible reasons:
XATTR:0, CROSS_RENAME:0, JOURNAL_FLAG_CHANGE:0, NO_MEM:0, SWAP_BOOT:0,
RESIZE:0, RENAME_DIR:0, FALLOC_RANGE:0, INODE_JOURNAL_DATA:16;
num_commits:6, ineligible: 6, numblks: 3

So in short, this patch guarantees that in case of rename whiteout, we
fall back to full commits.

Amir mentioned that instead of creating a new whiteout object for
every rename, we can create a static whiteout object with irrelevant
nlink. That will make fast commits to not fall back to full
commit. But until this happens, this patch will ensure correctness by
falling back to full commits.

Fixes: 8016e29f43 ("ext4: fast commit recovery path")
Cc: stable@kernel.org
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20210316221921.1124955-1-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-03-21 00:38:18 -04:00
zhangyi (F)
5dccdc5a19 ext4: do not iput inode under running transaction in ext4_rename()
In ext4_rename(), when RENAME_WHITEOUT failed to add new entry into
directory, it ends up dropping new created whiteout inode under the
running transaction. After commit <9b88f9fb0d2> ("ext4: Do not iput inode
under running transaction"), we follow the assumptions that evict() does
not get called from a transaction context but in ext4_rename() it breaks
this suggestion. Although it's not a real problem, better to obey it, so
this patch add inode to orphan list and stop transaction before final
iput().

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20210303131703.330415-2-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-03-21 00:09:14 -04:00
zhangyi (F)
b7ff91fd03 ext4: find old entry again if failed to rename whiteout
If we failed to add new entry on rename whiteout, we cannot reset the
old->de entry directly, because the old->de could have moved from under
us during make indexed dir. So find the old entry again before reset is
needed, otherwise it may corrupt the filesystem as below.

  /dev/sda: Entry '00000001' in ??? (12) has deleted/unused inode 15. CLEARED.
  /dev/sda: Unattached inode 75
  /dev/sda: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.

Fixes: 6b4b8e6b4a ("ext4: fix bug for rename with RENAME_WHITEOUT")
Cc: stable@vger.kernel.org
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20210303131703.330415-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-03-21 00:03:39 -04:00
Linus Torvalds
6f9972bbfe Miscellaneous ext4 cleanups and bug fixes. Pretty boring this
cycle...
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "Miscellaneous ext4 cleanups and bug fixes. Pretty boring this cycle..."

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: add .kunitconfig fragment to enable ext4-specific tests
  ext: EXT4_KUNIT_TESTS should depend on EXT4_FS instead of selecting it
  ext4: reset retry counter when ext4_alloc_file_blocks() makes progress
  ext4: fix potential htree index checksum corruption
  ext4: factor out htree rep invariant check
  ext4: Change list_for_each* to list_for_each_entry*
  ext4: don't try to processed freed blocks until mballoc is initialized
  ext4: use DEFINE_MUTEX() for mutex lock
2021-02-25 10:06:55 -08:00
Theodore Ts'o
b5776e7524 ext4: fix potential htree index checksum corruption
In the case where we need to do an interior node split, and
immediately afterwards, we are unable to allocate a new directory leaf
block due to ENOSPC, the directory index checksum's will not be filled
in correctly (and indeed, will not be correctly journalled).

This looks like a bug that was introduced when we added largedir
support.  The original code doesn't make any sense (and should have
been caught in code review), but it was hidden because most of the
time, the index node checksum will be set by do_split().  But if
do_split bails out due to ENOSPC, then ext4_handle_dirty_dx_node()
won't get called, and so the directory index checksum field will not
get set, leading to:

EXT4-fs error (device sdb): dx_probe:858: inode #6635543: block 4022: comm nfsd: Directory index failed checksum

Google-Bug-Id: 176345532
Fixes: e08ac99fa2 ("ext4: add largedir feature")
Cc: Artem Blagodarenko <artem.blagodarenko@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-02-04 00:05:20 -05:00
Vinicius Tinti
c6c818e50d ext4: factor out htree rep invariant check
This patch moves some debugging code which is used to validate the
hash tree node when doing a binary search of an htree node into a
separate function, which is disabled by default (since it is only used
by developers when they are modifying the htree code paths).

In addition to cleaning up the code to make it more maintainable, it
silences a Clang compiler warning when -Wunreachable-code-aggressive
is enabled.  (There is no plan to enable this warning by default, since
there it has far too many false positives; nevertheless, this commit
reduces one of the many false positives by one.)

Signed-off-by: Vinicius Tinti <viniciustinti@gmail.com>
Link: https://lore.kernel.org/r/20210202162837.129631-1-viniciustinti@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-02-03 00:34:02 -05:00
Christian Brauner
14f3db5542
ext4: support idmapped mounts
Enable idmapped mounts for ext4. All dedicated helpers we need for this
exist. So this basically just means we're passing down the
user_namespace argument from the VFS methods to the relevant helpers.

Let's create simple example where we idmap an ext4 filesystem:

 root@f2-vm:~# truncate -s 5G ext4.img

 root@f2-vm:~# mkfs.ext4 ./ext4.img
 mke2fs 1.45.5 (07-Jan-2020)
 Discarding device blocks: done
 Creating filesystem with 1310720 4k blocks and 327680 inodes
 Filesystem UUID: 3fd91794-c6ca-4b0f-9964-289a000919cf
 Superblock backups stored on blocks:
         32768, 98304, 163840, 229376, 294912, 819200, 884736

 Allocating group tables: done
 Writing inode tables: done
 Creating journal (16384 blocks): done
 Writing superblocks and filesystem accounting information: done

 root@f2-vm:~# losetup -f --show ./ext4.img
 /dev/loop0

 root@f2-vm:~# mount /dev/loop0 /mnt

 root@f2-vm:~# ls -al /mnt/
 total 24
 drwxr-xr-x  3 root root  4096 Oct 28 13:34 .
 drwxr-xr-x 30 root root  4096 Oct 28 13:22 ..
 drwx------  2 root root 16384 Oct 28 13:34 lost+found

 # Let's create an idmapped mount at /idmapped1 where we map uid and gid
 # 0 to uid and gid 1000
 root@f2-vm:/# ./mount-idmapped --map-mount b:0:1000:1 /mnt/ /idmapped1/

 root@f2-vm:/# ls -al /idmapped1/
 total 24
 drwxr-xr-x  3 ubuntu ubuntu  4096 Oct 28 13:34 .
 drwxr-xr-x 30 root   root    4096 Oct 28 13:22 ..
 drwx------  2 ubuntu ubuntu 16384 Oct 28 13:34 lost+found

 # Let's create an idmapped mount at /idmapped2 where we map uid and gid
 # 0 to uid and gid 2000
 root@f2-vm:/# ./mount-idmapped --map-mount b:0:2000:1 /mnt/ /idmapped2/

 root@f2-vm:/# ls -al /idmapped2/
 total 24
 drwxr-xr-x  3 2000 2000  4096 Oct 28 13:34 .
 drwxr-xr-x 31 root root  4096 Oct 28 13:39 ..
 drwx------  2 2000 2000 16384 Oct 28 13:34 lost+found

Let's create another example where we idmap the rootfs filesystem
without a mapping for uid 0 and gid 0:

 # Create an idmapped mount of for a full POSIX range of rootfs under
 # /mnt but without a mapping for uid 0 to reduce attack surface

 root@f2-vm:/# ./mount-idmapped --map-mount b:1:1:65536 / /mnt/

 # Since we don't have a mapping for uid and gid 0 all files owned by
 # uid and gid 0 should show up as uid and gid 65534:
 root@f2-vm:/# ls -al /mnt/
 total 664
 drwxr-xr-x 31 nobody nogroup   4096 Oct 28 13:39 .
 drwxr-xr-x 31 root   root      4096 Oct 28 13:39 ..
 lrwxrwxrwx  1 nobody nogroup      7 Aug 25 07:44 bin -> usr/bin
 drwxr-xr-x  4 nobody nogroup   4096 Oct 28 13:17 boot
 drwxr-xr-x  2 nobody nogroup   4096 Aug 25 07:48 dev
 drwxr-xr-x 81 nobody nogroup   4096 Oct 28 04:00 etc
 drwxr-xr-x  4 nobody nogroup   4096 Oct 28 04:00 home
 lrwxrwxrwx  1 nobody nogroup      7 Aug 25 07:44 lib -> usr/lib
 lrwxrwxrwx  1 nobody nogroup      9 Aug 25 07:44 lib32 -> usr/lib32
 lrwxrwxrwx  1 nobody nogroup      9 Aug 25 07:44 lib64 -> usr/lib64
 lrwxrwxrwx  1 nobody nogroup     10 Aug 25 07:44 libx32 -> usr/libx32
 drwx------  2 nobody nogroup  16384 Aug 25 07:47 lost+found
 drwxr-xr-x  2 nobody nogroup   4096 Aug 25 07:44 media
 drwxr-xr-x 31 nobody nogroup   4096 Oct 28 13:39 mnt
 drwxr-xr-x  2 nobody nogroup   4096 Aug 25 07:44 opt
 drwxr-xr-x  2 nobody nogroup   4096 Apr 15  2020 proc
 drwx--x--x  6 nobody nogroup   4096 Oct 28 13:34 root
 drwxr-xr-x  2 nobody nogroup   4096 Aug 25 07:46 run
 lrwxrwxrwx  1 nobody nogroup      8 Aug 25 07:44 sbin -> usr/sbin
 drwxr-xr-x  2 nobody nogroup   4096 Aug 25 07:44 srv
 drwxr-xr-x  2 nobody nogroup   4096 Apr 15  2020 sys
 drwxrwxrwt 10 nobody nogroup   4096 Oct 28 13:19 tmp
 drwxr-xr-x 14 nobody nogroup   4096 Oct 20 13:00 usr
 drwxr-xr-x 12 nobody nogroup   4096 Aug 25 07:45 var

 # Since we do have a mapping for uid and gid 1000 all files owned by
 # uid and gid 1000 should simply show up as uid and gid 1000:
 root@f2-vm:/# ls -al /mnt/home/ubuntu/
 total 40
 drwxr-xr-x 3 ubuntu ubuntu  4096 Oct 28 00:43 .
 drwxr-xr-x 4 nobody nogroup 4096 Oct 28 04:00 ..
 -rw------- 1 ubuntu ubuntu  2936 Oct 28 12:26 .bash_history
 -rw-r--r-- 1 ubuntu ubuntu   220 Feb 25  2020 .bash_logout
 -rw-r--r-- 1 ubuntu ubuntu  3771 Feb 25  2020 .bashrc
 -rw-r--r-- 1 ubuntu ubuntu   807 Feb 25  2020 .profile
 -rw-r--r-- 1 ubuntu ubuntu     0 Oct 16 16:11 .sudo_as_admin_successful
 -rw------- 1 ubuntu ubuntu  1144 Oct 28 00:43 .viminfo

Link: https://lore.kernel.org/r/20210121131959.646623-39-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-ext4@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:43:46 +01:00
Christian Brauner
549c729771
fs: make helpers idmap mount aware
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.

As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.

Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:20 +01:00
Linus Torvalds
0bc9bc1d8b A number of bug fixes for ext4:
* For the new fast_commit feature
    * Fix some error handling codepaths in whiteout handling and
      mountpoint sampling
    * Fix how we write ext4_error information so it goes through the journal
      when journalling is active, to avoid races that can lead to lost
      error information, superblock checksum failures, or DIF/DIX features.
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 fixes from Ted Ts'o:
 "A number of bug fixes for ext4:

   - Fix for the new fast_commit feature

   - Fix some error handling codepaths in whiteout handling and
     mountpoint sampling

   - Fix how we write ext4_error information so it goes through the
     journal when journalling is active, to avoid races that can lead to
     lost error information, superblock checksum failures, or DIF/DIX
     features"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: remove expensive flush on fast commit
  ext4: fix bug for rename with RENAME_WHITEOUT
  ext4: fix wrong list_splice in ext4_fc_cleanup
  ext4: use IS_ERR instead of IS_ERR_OR_NULL and set inode null when IS_ERR
  ext4: don't leak old mountpoint samples
  ext4: drop ext4_handle_dirty_super()
  ext4: fix superblock checksum failure when setting password salt
  ext4: use sbi instead of EXT4_SB(sb) in ext4_update_super()
  ext4: save error info to sb through journal if available
  ext4: protect superblock modifications with a buffer lock
  ext4: drop sync argument of ext4_commit_super()
  ext4: combine ext4_handle_error() and save_error_info()
2021-01-15 14:54:24 -08:00
yangerkun
6b4b8e6b4a ext4: fix bug for rename with RENAME_WHITEOUT
We got a "deleted inode referenced" warning cross our fsstress test. The
bug can be reproduced easily with following steps:

  cd /dev/shm
  mkdir test/
  fallocate -l 128M img
  mkfs.ext4 -b 1024 img
  mount img test/
  dd if=/dev/zero of=test/foo bs=1M count=128
  mkdir test/dir/ && cd test/dir/
  for ((i=0;i<1000;i++)); do touch file$i; done # consume all block
  cd ~ && renameat2(AT_FDCWD, /dev/shm/test/dir/file1, AT_FDCWD,
    /dev/shm/test/dir/dst_file, RENAME_WHITEOUT) # ext4_add_entry in
    ext4_rename will return ENOSPC!!
  cd /dev/shm/ && umount test/ && mount img test/ && ls -li test/dir/file1
  We will get the output:
  "ls: cannot access 'test/dir/file1': Structure needs cleaning"
  and the dmesg show:
  "EXT4-fs error (device loop0): ext4_lookup:1626: inode #2049: comm ls:
  deleted inode referenced: 139"

ext4_rename will create a special inode for whiteout and use this 'ino'
to replace the source file's dir entry 'ino'. Once error happens
latter(the error above was the ENOSPC return from ext4_add_entry in
ext4_rename since all space has been consumed), the cleanup do drop the
nlink for whiteout, but forget to restore 'ino' with source file. This
will trigger the bug describle as above.

Signed-off-by: yangerkun <yangerkun@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
Fixes: cd808deced ("ext4: support RENAME_WHITEOUT")
Link: https://lore.kernel.org/r/20210105062857.3566-1-yangerkun@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-01-15 14:41:31 -05:00
Linus Torvalds
555a6e8c11 Various bug fixes and cleanups for ext4; no new features this cycle.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "Various bug fixes and cleanups for ext4; no new features this cycle"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (29 commits)
  ext4: remove unnecessary wbc parameter from ext4_bio_write_page
  ext4: avoid s_mb_prefetch to be zero in individual scenarios
  ext4: defer saving error info from atomic context
  ext4: simplify ext4 error translation
  ext4: move functions in super.c
  ext4: make ext4_abort() use __ext4_error()
  ext4: standardize error message in ext4_protect_reserved_inode()
  ext4: remove redundant sb checksum recomputation
  ext4: don't remount read-only with errors=continue on reboot
  ext4: fix deadlock with fs freezing and EA inodes
  jbd2: add a helper to find out number of fast commit blocks
  ext4: make fast_commit.h byte identical with e2fsprogs/fast_commit.h
  ext4: fix fall-through warnings for Clang
  ext4: add docs about fast commit idempotence
  ext4: remove the unused EXT4_CURRENT_REV macro
  ext4: fix an IS_ERR() vs NULL check
  ext4: check for invalid block size early when mounting a file system
  ext4: fix a memory leak of ext4_free_data
  ext4: delete nonsensical (commented-out) code inside ext4_xattr_block_set()
  ext4: update ext4_data_block_valid related comments
  ...
2020-12-24 14:16:02 -08:00
Jan Kara
a3f5cf14ff ext4: drop ext4_handle_dirty_super()
The wrapper is now useless since it does what
ext4_handle_dirty_metadata() does. Just remove it.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201216101844.22917-9-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-22 13:08:46 -05:00
Jan Kara
05c2c00f37 ext4: protect superblock modifications with a buffer lock
Protect all superblock modifications (including checksum computation)
with a superblock buffer lock. That way we are sure computed checksum
matches current superblock contents (a mismatch could cause checksum
failures in nojournal mode or if an unjournalled superblock update races
with a journalled one). Also we avoid modifying superblock contents
while it is being written out (which can cause DIF/DIX failures if we
are running in nojournal mode).

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201216101844.22917-4-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-22 13:08:46 -05:00
Linus Torvalds
ff49c86f27 f2fs-for-5.11-rc1
In this round, we've made more work into per-file compression support. For
 example, F2FS_IOC_GET|SET_COMPRESS_OPTION provides a way to change the
 algorithm or cluster size per file. F2FS_IOC_COMPRESS|DECOMPRESS_FILE provides
 a way to compress and decompress the existing normal files manually along with
 a new mount option, compress_mode=fs|user, which can control who compresses the
 data. Chao also added a checksum feature with a mount option so that we are able
 to detect any corrupted cluster. In addition, Daniel contributed casefolding
 with encryption patch, which will be used for Android devices.
 
 Enhancement:
  - add ioctls and mount option to manage per-file compression feature
  - support casefolding with encryption
  - support checksum for compressed cluster
  - avoid IO starvation by replacing mutex with rwsem
  - add sysfs, max_io_bytes, to control max bio size
 
 Bug fix:
  - fix use-after-free issue when compression and fsverity are enabled
  - fix consistency corruption during fault injection test
  - fix data offset for lseek
  - get rid of buffer_head which has 32bits limit in fiemap
  - fix some bugs in multi-partitions support
  - fix nat entry count calculation in shrinker
  - fix some stat information
 
 And, we've refactored some logics and fix minor bugs as well.
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Merge tag 'f2fs-for-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've made more work into per-file compression support.

  For example, F2FS_IOC_GET | SET_COMPRESS_OPTION provides a way to
  change the algorithm or cluster size per file. F2FS_IOC_COMPRESS |
  DECOMPRESS_FILE provides a way to compress and decompress the existing
  normal files manually.

  There is also a new mount option, compress_mode=fs|user, which can
  control who compresses the data.

  Chao also added a checksum feature with a mount option so that
  we are able to detect any corrupted cluster.

  In addition, Daniel contributed casefolding with encryption patch,
  which will be used for Android devices.

  Summary:

  Enhancements:
   - add ioctls and mount option to manage per-file compression feature
   - support casefolding with encryption
   - support checksum for compressed cluster
   - avoid IO starvation by replacing mutex with rwsem
   - add sysfs, max_io_bytes, to control max bio size

  Bug fixes:
   - fix use-after-free issue when compression and fsverity are enabled
   - fix consistency corruption during fault injection test
   - fix data offset for lseek
   - get rid of buffer_head which has 32bits limit in fiemap
   - fix some bugs in multi-partitions support
   - fix nat entry count calculation in shrinker
   - fix some stat information

  And, we've refactored some logics and fix minor bugs as well"

* tag 'f2fs-for-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (36 commits)
  f2fs: compress: fix compression chksum
  f2fs: fix shift-out-of-bounds in sanity_check_raw_super()
  f2fs: fix race of pending_pages in decompression
  f2fs: fix to account inline xattr correctly during recovery
  f2fs: inline: fix wrong inline inode stat
  f2fs: inline: correct comment in f2fs_recover_inline_data
  f2fs: don't check PAGE_SIZE again in sanity_check_raw_super()
  f2fs: convert to F2FS_*_INO macro
  f2fs: introduce max_io_bytes, a sysfs entry, to limit bio size
  f2fs: don't allow any writes on readonly mount
  f2fs: avoid race condition for shrinker count
  f2fs: add F2FS_IOC_DECOMPRESS_FILE and F2FS_IOC_COMPRESS_FILE
  f2fs: add compress_mode mount option
  f2fs: Remove unnecessary unlikely()
  f2fs: init dirty_secmap incorrectly
  f2fs: remove buffer_head which has 32bits limit
  f2fs: fix wrong block count instead of bytes
  f2fs: use new conversion functions between blks and bytes
  f2fs: rename logical_to_blk and blk_to_logical
  f2fs: fix kbytes written stat for multi-device case
  ...
2020-12-17 11:18:00 -08:00
Chunguang Xu
837c23fbc1 ext4: use ASSERT() to replace J_ASSERT()
There are currently multiple forms of assertion, such as J_ASSERT().
J_ASEERT() is provided for the jbd module, which is a public module.
Maybe we should use custom ASSERT() like other file systems, such as
xfs, which would be better.

Signed-off-by: Chunguang Xu <brookxu@tencent.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/1604764698-4269-1-git-send-email-brookxu@tencent.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-03 09:36:57 -05:00
Daniel Rosenberg
bb9cd9106b fscrypt: Have filesystems handle their d_ops
This shifts the responsibility of setting up dentry operations from
fscrypt to the individual filesystems, allowing them to have their own
operations while still setting fscrypt's d_revalidate as appropriate.

Most filesystems can just use generic_set_encrypted_ci_d_ops, unless
they have their own specific dentry operations as well. That operation
will set the minimal d_ops required under the circumstances.

Since the fscrypt d_ops are set later on, we must set all d_ops there,
since we cannot adjust those later on. This should not result in any
change in behavior.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Acked-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-12-02 22:00:21 -08:00
Eric Biggers
ec0caa974c fscrypt: introduce fscrypt_prepare_readdir()
The last remaining use of fscrypt_get_encryption_info() from filesystems
is for readdir (->iterate_shared()).  Every other call is now in
fs/crypto/ as part of some other higher-level operation.

We need to add a new argument to fscrypt_get_encryption_info() to
indicate whether the encryption policy is allowed to be unrecognized or
not.  Doing this is easier if we can work with high-level operations
rather than direct filesystem use of fscrypt_get_encryption_info().

So add a function fscrypt_prepare_readdir() which wraps the call to
fscrypt_get_encryption_info() for the readdir use case.

Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20201203022041.230976-6-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-12-02 18:25:01 -08:00
Eric Biggers
91d0d89241 ext4: don't call fscrypt_get_encryption_info() from dx_show_leaf()
The call to fscrypt_get_encryption_info() in dx_show_leaf() is too low
in the call tree; fscrypt_get_encryption_info() should have already been
called when starting the directory operation.  And indeed, it already
is.  Moreover, the encryption key is guaranteed to already be available
because dx_show_leaf() is only called when adding a new directory entry.

And even if the key wasn't available, dx_show_leaf() uses
fscrypt_fname_disk_to_usr() which knows how to create a no-key name.

So for the above reasons, and because it would be desirable to stop
exporting fscrypt_get_encryption_info() directly to filesystems, remove
the call to fscrypt_get_encryption_info() from dx_show_leaf().

Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20201203022041.230976-5-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-12-02 18:25:01 -08:00
Eric Biggers
75d18cd186 ext4: prevent creating duplicate encrypted filenames
As described in "fscrypt: add fscrypt_is_nokey_name()", it's possible to
create a duplicate filename in an encrypted directory by creating a file
concurrently with adding the directory's encryption key.

Fix this bug on ext4 by rejecting no-key dentries in ext4_add_entry().

Note that the duplicate check in ext4_find_dest_de() sometimes prevented
this bug.  However in many cases it didn't, since ext4_find_dest_de()
doesn't examine every dentry.

Fixes: 4461471107 ("ext4 crypto: enable filename encryption")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201118075609.120337-3-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-11-24 15:10:27 -08:00
Harshad Shirwadkar
a80f7fcf18 ext4: fixup ext4_fc_track_* functions' signature
Firstly, pass handle to all ext4_fc_track_* functions and use
transaction id found in handle->h_transaction->h_tid for tracking fast
commit updates. Secondly, don't pass inode to
ext4_fc_track_link/create/unlink functions. inode can be found inside
these functions as d_inode(dentry). However, rename path is an
exeception. That's because in that case, we need inode that's not same
as d_inode(dentry). To handle that, add a couple of low-level wrapper
functions that take inode and dentry as arguments.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201106035911.1942128-5-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-11-06 23:01:02 -05:00
Daniel Rosenberg
f8f4acb6cd ext4: use generic casefolding support
This switches ext4 over to the generic support provided in libfs.

Since casefolded dentries behave the same in ext4 and f2fs, we decrease
the maintenance burden by unifying them, and any optimizations will
immediately apply to both.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20201028050820.1636571-1-drosen@google.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-10-28 13:43:13 -04:00
Linus Torvalds
96485e4462 The siginificant new ext4 feature this time around is Harshad's new
fast_commit mode.  In addition, thanks to Mauricio for fixing a race
 where mmap'ed pages that are being changed in parallel with a
 data=journal transaction commit could result in bad checksums in the
 failure that could cause journal replays to fail.  Also notable is
 Ritesh's buffered write optimization which can result in significant
 improvements on parallel write workloads.  (The kernel test robot
 reported a 330.6% improvement on fio.write_iops on a 96 core system
 using DAX[1].)
 
 Besides that, we have the usual miscellaneous cleanups and bug fixes.
 
 [1] https://lore.kernel.org/r/20200925071217.GO28663@shao2-debian
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "The siginificant new ext4 feature this time around is Harshad's new
  fast_commit mode.

  In addition, thanks to Mauricio for fixing a race where mmap'ed pages
  that are being changed in parallel with a data=journal transaction
  commit could result in bad checksums in the failure that could cause
  journal replays to fail.

  Also notable is Ritesh's buffered write optimization which can result
  in significant improvements on parallel write workloads. (The kernel
  test robot reported a 330.6% improvement on fio.write_iops on a 96
  core system using DAX)

  Besides that, we have the usual miscellaneous cleanups and bug fixes"

Link: https://lore.kernel.org/r/20200925071217.GO28663@shao2-debian

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (46 commits)
  ext4: fix invalid inode checksum
  ext4: add fast commit stats in procfs
  ext4: add a mount opt to forcefully turn fast commits on
  ext4: fast commit recovery path
  jbd2: fast commit recovery path
  ext4: main fast-commit commit path
  jbd2: add fast commit machinery
  ext4 / jbd2: add fast commit initialization
  ext4: add fast_commit feature and handling for extended mount options
  doc: update ext4 and journalling docs to include fast commit feature
  ext4: Detect already used quota file early
  jbd2: avoid transaction reuse after reformatting
  ext4: use the normal helper to get the actual inode
  ext4: fix bs < ps issue reported with dioread_nolock mount opt
  ext4: data=journal: write-protect pages on j_submit_inode_data_buffers()
  ext4: data=journal: fixes for ext4_page_mkwrite()
  jbd2, ext4, ocfs2: introduce/use journal callbacks j_submit|finish_inode_data_buffers()
  jbd2: introduce/export functions jbd2_journal_submit|finish_inode_data_buffers()
  ext4: introduce ext4_sb_bread_unmovable() to replace sb_bread_unmovable()
  ext4: use ext4_sb_bread() instead of sb_bread()
  ...
2020-10-22 10:31:08 -07:00
Harshad Shirwadkar
8016e29f43 ext4: fast commit recovery path
This patch adds fast commit recovery path support for Ext4 file
system. We add several helper functions that are similar in spirit to
e2fsprogs journal recovery path handlers. Example of such functions
include - a simple block allocator, idempotent block bitmap update
function etc. Using these routines and the fast commit log in the fast
commit area, the recovery path (ext4_fc_replay()) performs fast commit
log recovery.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201015203802.3597742-8-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-10-21 23:22:38 -04:00
Harshad Shirwadkar
aa75f4d3da ext4: main fast-commit commit path
This patch adds main fast commit commit path handlers. The overall
patch can be divided into two inter-related parts:

(A) Metadata updates tracking

    This part consists of helper functions to track changes that need
    to be committed during a commit operation. These updates are
    maintained by Ext4 in different in-memory queues. Following are
    the APIs and their short description that are implemented in this
    patch:

    - ext4_fc_track_link/unlink/creat() - Track unlink. link and creat
      operations
    - ext4_fc_track_range() - Track changed logical block offsets
      inodes
    - ext4_fc_track_inode() - Track inodes
    - ext4_fc_mark_ineligible() - Mark file system fast commit
      ineligible()
    - ext4_fc_start_update() / ext4_fc_stop_update() /
      ext4_fc_start_ineligible() / ext4_fc_stop_ineligible() These
      functions are useful for co-ordinating inode updates with
      commits.

(B) Main commit Path

    This part consists of functions to convert updates tracked in
    in-memory data structures into on-disk commits. Function
    ext4_fc_commit() is the main entry point to commit path.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201015203802.3597742-6-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-10-21 23:22:37 -04:00
Nikolay Borisov
15ed2851b0 ext4: remove unused argument from ext4_(inc|dec)_count
The 'handle' argument is not used for anything so simply remove it.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200826133116.11592-1-nborisov@suse.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-10-18 10:36:13 -04:00
Jeff Layton
8b10fe6898 fscrypt: drop unused inode argument from fscrypt_fname_alloc_buffer
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20200810142139.487631-1-jlayton@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-09-07 15:27:42 -07:00
Kyoungho Koo
2fe34d2938 ext4: remove unused parameter of ext4_generic_delete_entry function
The ext4_generic_delete_entry function does not use the parameter
handle, so it can be removed.

Signed-off-by: Kyoungho Koo <rnrudgh@gmail.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200810080701.GA14160@koo-Z370-HD3
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-08-18 14:25:54 -04:00
Jan Kara
7303cb5bfe ext4: fix checking of directory entry validity for inline directories
ext4_search_dir() and ext4_generic_delete_entry() can be called both for
standard director blocks and for inline directories stored inside inode
or inline xattr space. For the second case we didn't call
ext4_check_dir_entry() with proper constraints that could result in
accepting corrupted directory entry as well as false positive filesystem
errors like:

EXT4-fs error (device dm-0): ext4_search_dir:1395: inode #28320400:
block 113246792: comm dockerd: bad entry in directory: directory entry too
close to block end - offset=0, inode=28320403, rec_len=32, name_len=8,
size=4096

Fix the arguments passed to ext4_check_dir_entry().

Fixes: 109ba779d6 ("ext4: check for directory entries too close to block end")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200731162135.8080-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-08-07 16:04:27 -04:00
Yi Zhuang
e5f78159d6 ext4: lost matching-pair of trace in ext4_unlink
If dquot_initialize() return non-zero and trace of ext4_unlink_enter/exit
enabled then the matching-pair of trace_exit will lost in log.

Signed-off-by: Yi Zhuang <zhuangyi1@huawei.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200629122621.129953-1-zhuangyi1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-08-06 00:56:08 -04:00
Eric Sandeen
5872331b3d ext4: fix potential negative array index in do_split()
If for any reason a directory passed to do_split() does not have enough
active entries to exceed half the size of the block, we can end up
iterating over all "count" entries without finding a split point.

In this case, count == move, and split will be zero, and we will
attempt a negative index into map[].

Guard against this by detecting this case, and falling back to
split-to-half-of-count instead; in this case we will still have
plenty of space (> half blocksize) in each split block.

Fixes: ef2b02d3e6 ("ext34: ensure do_split leaves enough free space in both blocks")
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/f53e246b-647c-64bb-16ec-135383c70ad7@redhat.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-08-06 00:11:16 -04:00
Harshad Shirwadkar
4209ae12b1 ext4: handle ext4_mark_inode_dirty errors
ext4_mark_inode_dirty() can fail for real reasons. Ignoring its return
value may lead ext4 to ignore real failures that would result in
corruption / crashes. Harden ext4_mark_inode_dirty error paths to fail
as soon as possible and return errors to the caller whenever
appropriate.

One of the possible scnearios when this bug could affected is that
while creating a new inode, its directory entry gets added
successfully but while writing the inode itself mark_inode_dirty
returns error which is ignored. This would result in inconsistency
that the directory entry points to a non-existent inode.

Ran gce-xfstests smoke tests and verified that there were no
regressions.

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20200427013438.219117-1-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-06-03 23:16:50 -04:00
Theodore Ts'o
54d3adbc29 ext4: save all error info in save_error_info() and drop ext4_set_errno()
Using a separate function, ext4_set_errno() to set the errno is
problematic because it doesn't do the right thing once
s_last_error_errorcode is non-zero.  It's also less racy to set all of
the error information all at once.  (Also, as a bonus, it shrinks code
size slightly.)

Link: https://lore.kernel.org/r/20200329020404.686965-1-tytso@mit.edu
Fixes: 878520ac45 ("ext4: save the error code which triggered...")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-04-01 17:29:06 -04:00
Gustavo A. R. Silva
6cfb061fe9 ext4: use flexible-array members in struct dx_node and struct dx_root
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: https://lore.kernel.org/r/20200213160648.GA7054@embeddedor
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-03-05 20:25:05 -05:00
Shijie Luo
9424ef56e1 ext4: add cond_resched() to __ext4_find_entry()
We tested a soft lockup problem in linux 4.19 which could also
be found in linux 5.x.

When dir inode takes up a large number of blocks, and if the
directory is growing when we are searching, it's possible the
restart branch could be called many times, and the do while loop
could hold cpu a long time.

Here is the call trace in linux 4.19.

[  473.756186] Call trace:
[  473.756196]  dump_backtrace+0x0/0x198
[  473.756199]  show_stack+0x24/0x30
[  473.756205]  dump_stack+0xa4/0xcc
[  473.756210]  watchdog_timer_fn+0x300/0x3e8
[  473.756215]  __hrtimer_run_queues+0x114/0x358
[  473.756217]  hrtimer_interrupt+0x104/0x2d8
[  473.756222]  arch_timer_handler_virt+0x38/0x58
[  473.756226]  handle_percpu_devid_irq+0x90/0x248
[  473.756231]  generic_handle_irq+0x34/0x50
[  473.756234]  __handle_domain_irq+0x68/0xc0
[  473.756236]  gic_handle_irq+0x6c/0x150
[  473.756238]  el1_irq+0xb8/0x140
[  473.756286]  ext4_es_lookup_extent+0xdc/0x258 [ext4]
[  473.756310]  ext4_map_blocks+0x64/0x5c0 [ext4]
[  473.756333]  ext4_getblk+0x6c/0x1d0 [ext4]
[  473.756356]  ext4_bread_batch+0x7c/0x1f8 [ext4]
[  473.756379]  ext4_find_entry+0x124/0x3f8 [ext4]
[  473.756402]  ext4_lookup+0x8c/0x258 [ext4]
[  473.756407]  __lookup_hash+0x8c/0xe8
[  473.756411]  filename_create+0xa0/0x170
[  473.756413]  do_mkdirat+0x6c/0x140
[  473.756415]  __arm64_sys_mkdirat+0x28/0x38
[  473.756419]  el0_svc_common+0x78/0x130
[  473.756421]  el0_svc_handler+0x38/0x78
[  473.756423]  el0_svc+0x8/0xc
[  485.755156] watchdog: BUG: soft lockup - CPU#2 stuck for 22s! [tmp:5149]

Add cond_resched() to avoid soft lockup and to provide a better
system responding.

Link: https://lore.kernel.org/r/20200215080206.13293-1-luoshijie1@huawei.com
Signed-off-by: Shijie Luo <luoshijie1@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org
2020-02-19 23:53:52 -05:00
Jan Kara
48a3431195 ext4: fix checksum errors with indexed dirs
DIR_INDEX has been introduced as a compat ext4 feature. That means that
even kernels / tools that don't understand the feature may modify the
filesystem. This works because for kernels not understanding indexed dir
format, internal htree nodes appear just as empty directory entries.
Index dir aware kernels then check the htree structure is still
consistent before using the data. This all worked reasonably well until
metadata checksums were introduced. The problem is that these
effectively made DIR_INDEX only ro-compatible because internal htree
nodes store checksums in a different place than normal directory blocks.
Thus any modification ignorant to DIR_INDEX (or just clearing
EXT4_INDEX_FL from the inode) will effectively cause checksum mismatch
and trigger kernel errors. So we have to be more careful when dealing
with indexed directories on filesystems with checksumming enabled.

1) We just disallow loading any directory inodes with EXT4_INDEX_FL when
DIR_INDEX is not enabled. This is harsh but it should be very rare (it
means someone disabled DIR_INDEX on existing filesystem and didn't run
e2fsck), e2fsck can fix the problem, and we don't want to answer the
difficult question: "Should we rather corrupt the directory more or
should we ignore that DIR_INDEX feature is not set?"

2) When we find out htree structure is corrupted (but the filesystem and
the directory should in support htrees), we continue just ignoring htree
information for reading but we refuse to add new entries to the
directory to avoid corrupting it more.

Link: https://lore.kernel.org/r/20200210144316.22081-1-jack@suse.cz
Fixes: dbe8944404 ("ext4: Calculate and verify checksums for htree nodes")
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
2020-02-13 11:56:19 -05:00
Eric Biggers
64c314ff82 ext4: remove unnecessary ifdefs in htree_dirblock_to_tree()
The ifdefs for CONFIG_FS_ENCRYPTION in htree_dirblock_to_tree() are
unnecessary, as the called functions are already stubbed out when
!CONFIG_FS_ENCRYPTION.  Remove them.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191209213225.18477-1-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2020-01-17 16:24:52 -05:00
Theodore Ts'o
46f870d690 ext4: simulate various I/O and checksum errors when reading metadata
This allows us to test various error handling code paths

Link: https://lore.kernel.org/r/20191209012317.59398-1-tytso@mit.edu
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-12-26 11:28:31 -05:00
Theodore Ts'o
878520ac45 ext4: save the error code which triggered an ext4_error() in the superblock
This allows the cause of an ext4_error() report to be categorized
based on whether it was triggered due to an I/O error, or an memory
allocation error, or other possible causes.  Most errors are caused by
a detected file system inconsistency, so the default code stored in
the superblock will be EXT4_ERR_EFSCORRUPTED.

Link: https://lore.kernel.org/r/20191204032335.7683-1-tytso@mit.edu
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-12-26 11:28:23 -05:00
Yunfeng Ye
68d7b2d838 ext4: fix unused-but-set-variable warning in ext4_add_entry()
Warning is found when compile with "-Wunused-but-set-variable":

fs/ext4/namei.c: In function ‘ext4_add_entry’:
fs/ext4/namei.c:2167:23: warning: variable ‘sbi’ set but not used
[-Wunused-but-set-variable]
  struct ext4_sb_info *sbi;
                       ^~~
Fix this by moving the variable @sbi under CONFIG_UNICODE.

Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/cb5eb904-224a-9701-c38f-cb23514b1fff@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-12-21 21:00:53 -05:00
Jan Kara
64d4ce8923 ext4: fix ext4_empty_dir() for directories with holes
Function ext4_empty_dir() doesn't correctly handle directories with
holes and crashes on bh->b_data dereference when bh is NULL. Reorganize
the loop to use 'offset' variable all the times instead of comparing
pointers to current direntry with bh->b_data pointer. Also add more
strict checking of '.' and '..' directory entries to avoid entering loop
in possibly invalid state on corrupted filesystems.

References: CVE-2019-19037
CC: stable@vger.kernel.org
Fixes: 4e19d6b65f ("ext4: allow directory holes")
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191202170213.4761-2-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-12-14 17:22:45 -05:00
Theodore Ts'o
c7df4a1ecb ext4: work around deleting a file with i_nlink == 0 safely
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 <tytso@mit.edu>
Cc: stable@kernel.org
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
2019-11-19 12:25:21 -05:00
Jan Kara
9b88f9fb0d ext4: Do not iput inode under running transaction
When ext4_mkdir(), ext4_symlink(), ext4_create(), or ext4_mknod() fail
to add entry into directory, it ends up dropping freshly created inode
under the running transaction and thus inode truncation happens under
that transaction. That breaks assumptions that evict() does not get
called from a transaction context and at least in ext4_symlink() case it
can result in inode eviction deadlocking in inode_wait_for_writeback()
when flush worker finds symlink inode, starts to write it back and
blocks on starting a transaction. So change the code in ext4_mkdir() and
ext4_add_nondir() to drop inode reference only after the transaction is
stopped. We also have to add inode to the orphan list in that case as
otherwise the inode would get leaked in case we crash before inode
deletion is committed.

CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-5-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 12:13:25 -05:00
Jan Kara
a9e26328ad ext4: Move marking of handle as sync to ext4_add_nondir()
Every caller of ext4_add_nondir() marks handle as sync if directory has
DIRSYNC set. Move this marking to ext4_add_nondir() so reduce some
duplication.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-4-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 12:13:25 -05:00
Theodore Ts'o
6456ca6520 ext4: fix kernel oops caused by spurious casefold flag
If an directory has the a casefold flag set without the casefold
feature set, s_encoding will not be initialized, and this will cause
the kernel to dereference a NULL pointer.  In addition to adding
checks to avoid these kernel oops, attempts to load inodes with the
casefold flag when the casefold feature is not enable will cause the
file system to be declared corrupted.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-09-03 01:43:17 -04:00
Gabriel Krisman Bertazi
96fcaf86c3 ext4: fix coverity warning on error path of filename setup
Fix the following coverity warning reported by Dan Carpenter:

fs/ext4/namei.c:1311 ext4_fname_setup_ci_filename()
	  warn: 'cf_name->len' unsigned <= 0

Fixes: 3ae72562ad ("ext4: optimize case-insensitive lookups")
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
2019-07-02 17:56:12 -04:00
Theodore Ts'o
7633b08b27 ext4: rename htree_inline_dir_to_tree() to ext4_inlinedir_to_tree()
Clean up namespace pollution by the inline_data code.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-06-21 21:57:00 -04:00
Theodore Ts'o
ddce3b9471 ext4: refactor initialize_dirent_tail()
Move the calculation of the location of the dirent tail into
initialize_dirent_tail().  Also prefix the function with ext4_ to fix
kernel namepsace polution.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-06-21 16:31:47 -04:00
Theodore Ts'o
f036adb399 ext4: rename "dirent_csum" functions to use "dirblock"
Functions such as ext4_dirent_csum_verify() and ext4_dirent_csum_set()
don't actually operate on a directory entry, but a directory block.
And while they take a struct ext4_dir_entry *dirent as an argument, it
had better be the first directory at the beginning of the direct
block, or things will go very wrong.

Rename the following functions so that things make more sense, and
remove a lot of confusing casts along the way:

   ext4_dirent_csum_verify	 -> ext4_dirblock_csum_verify
   ext4_dirent_csum_set		 -> ext4_dirblock_csum_set
   ext4_dirent_csum		 -> ext4_dirblock_csum
   ext4_handle_dirty_dirent_node -> ext4_handle_dirty_dirblock

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-06-21 15:49:26 -04:00