linux-toradex.git/fs/ext4, branch v4.1.14

Revert "ext4: remove block_device_ejected"

2015-09-29T17:25:58+00:00

commit bdfe0cbd746aa9b2509c2f6d6be17193cf7facd7 upstream.

This reverts commit 08439fec266c3cc5702953b4f54bdf5649357de0.

Unfortunately we still need to test for bdi->dev to avoid a crash when a
USB stick is yanked out while a file system is mounted:

   usb 2-2: USB disconnect, device number 2
   Buffer I/O error on dev sdb1, logical block 15237120, lost sync page write
   JBD2: Error -5 detected when updating journal superblock for sdb1-8.
   BUG: unable to handle kernel paging request at 34beb000
   IP: [] __percpu_counter_add+0x18/0xc0
   *pdpt = 0000000023db9001 *pde = 0000000000000000
   Oops: 0000 [#1] SMP
   CPU: 0 PID: 4083 Comm: umount Tainted: G     U     OE   4.1.1-040101-generic #201507011435
   Hardware name: LENOVO 7675CTO/7675CTO, BIOS 7NETC2WW (2.22 ) 03/22/2011
   task: ebf06b50 ti: ebebc000 task.ti: ebebc000
   EIP: 0060:[] EFLAGS: 00010082 CPU: 0
   EIP is at __percpu_counter_add+0x18/0xc0
   EAX: f21c8e88 EBX: f21c8e88 ECX: 00000000 EDX: 00000001
   ESI: 00000001 EDI: 00000000 EBP: ebebde60 ESP: ebebde40
    DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
   CR0: 8005003b CR2: 34beb000 CR3: 33354200 CR4: 000007f0
   Stack:
    c1abe100 edcb0098 edcb00ec ffffffff f21c8e68 ffffffff f21c8e68 f286d160
    ebebde84 c1160454 00000010 00000282 f72a77f8 00000984 f72a77f8 f286d160
    f286d170 ebebdea0 c11e613f 00000000 00000282 f72a77f8 edd7f4d0 00000000
   Call Trace:
    [] account_page_dirtied+0x74/0x110
    [] __set_page_dirty+0x3f/0xb0
    [] mark_buffer_dirty+0x53/0xc0
    [] ext4_commit_super+0x17b/0x250
    [] ext4_put_super+0xc1/0x320
    [] ? fsnotify_unmount_inodes+0x1aa/0x1c0
    [] ? evict_inodes+0xca/0xe0
    [] generic_shutdown_super+0x6a/0xe0
    [] ? prepare_to_wait_event+0xd0/0xd0
    [] ? unregister_shrinker+0x40/0x50
    [] kill_block_super+0x26/0x70
    [] deactivate_locked_super+0x45/0x80
    [] deactivate_super+0x47/0x60
    [] cleanup_mnt+0x39/0x80
    [] __cleanup_mnt+0x10/0x20
    [] task_work_run+0x91/0xd0
    [] do_notify_resume+0x7c/0x90
    [] work_notify
   Code: 8b 55 e8 e9 f4 fe ff ff 90 90 90 90 90 90 90 90 90 90 90 55 89 e5 83 ec 20 89 5d f4 89 c3 89 75 f8 89 d6 89 7d fc 89 cf 8b 48 14 <64> 8b 01 89 45 ec 89 c2 8b 45 08 c1 fa 1f 01 75 ec 89 55 f0 89
   EIP: [] __percpu_counter_add+0x18/0xc0 SS:ESP 0068:ebebde40
   CR2: 0000000034beb000
   ---[ end trace dd564a7bea834ecd ]---

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=101011

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

ext4: don't manipulate recovery flag when freezing no-journal fs

2015-09-29T17:25:58+00:00

commit c642dc9e1aaed953597e7092d7df329e6234096e upstream.

At some point along this sequence of changes:

f6e63f9 ext4: fold ext4_nojournal_sops into ext4_sops
bb04457 ext4: support freezing ext2 (nojournal) file systems
9ca9238 ext4: Use separate super_operations structure for no_journal filesystems

ext4 started setting needs_recovery on filesystems without journals
when they are unfrozen.  This makes no sense, and in fact confuses
blkid to the point where it doesn't recognize the filesystem at all.

(freeze ext2; unfreeze ext2; run blkid; see no output; run dumpe2fs,
see needs_recovery set on fs w/ no journal).

To fix this, don't manipulate the INCOMPAT_RECOVER feature on
filesystems without journals.

Reported-by: Stu Mark 
Reviewed-by: Jan Kara 
Signed-off-by: Eric Sandeen 
Signed-off-by: Theodore Ts'o 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

fs: create and use seq_show_option for escaping

2015-09-21T17:05:45+00:00

commit a068acf2ee77693e0bf39d6e07139ba704f461c3 upstream.

Many file systems that implement the show_options hook fail to correctly
escape their output which could lead to unescaped characters (e.g.  new
lines) leaking into /proc/mounts and /proc/[pid]/mountinfo files.  This
could lead to confusion, spoofed entries (resulting in things like
systemd issuing false d-bus "mount" notifications), and who knows what
else.  This looks like it would only be the root user stepping on
themselves, but it's possible weird things could happen in containers or
in other situations with delegated mount privileges.

Here's an example using overlay with setuid fusermount trusting the
contents of /proc/mounts (via the /etc/mtab symlink).  Imagine the use
of "sudo" is something more sneaky:

  $ BASE="ovl"
  $ MNT="$BASE/mnt"
  $ LOW="$BASE/lower"
  $ UP="$BASE/upper"
  $ WORK="$BASE/work/ 0 0
  none /proc fuse.pwn user_id=1000"
  $ mkdir -p "$LOW" "$UP" "$WORK"
  $ sudo mount -t overlay -o "lowerdir=$LOW,upperdir=$UP,workdir=$WORK" none /mnt
  $ cat /proc/mounts
  none /root/ovl/mnt overlay rw,relatime,lowerdir=ovl/lower,upperdir=ovl/upper,workdir=ovl/work/ 0 0
  none /proc fuse.pwn user_id=1000 0 0
  $ fusermount -u /proc
  $ cat /proc/mounts
  cat: /proc/mounts: No such file or directory

This fixes the problem by adding new seq_show_option and
seq_show_option_n helpers, and updating the vulnerable show_option
handlers to use them as needed.  Some, like SELinux, need to be open
coded due to unusual existing escape mechanisms.

[akpm@linux-foundation.org: add lost chunk, per Kees]
[keescook@chromium.org: seq_show_option should be using const parameters]
Signed-off-by: Kees Cook 
Acked-by: Serge Hallyn 
Acked-by: Jan Kara 
Acked-by: Paul Moore 
Cc: J. R. Okajima 
Signed-off-by: Kees Cook 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ext4: replace open coded nofail allocation in ext4_free_blocks()

2015-08-03T16:29:00+00:00

commit 7444a072c387a93ebee7066e8aee776954ab0e41 upstream.

ext4_free_blocks is looping around the allocation request and mimics
__GFP_NOFAIL behavior without any allocation fallback strategy. Let's
remove the open coded loop and replace it with __GFP_NOFAIL. Without the
flag the allocator has no way to find out never-fail requirement and
cannot help in any way.

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

ext4: correctly migrate a file with a hole at the beginning

2015-08-03T16:29:00+00:00

commit 8974fec7d72e3e02752fe0f27b4c3719c78d9a15 upstream.

Currently ext4_ind_migrate() doesn't correctly handle a file which
contains a hole at the beginning of the file.  This caused the migration
to be done incorrectly, and then if there is a subsequent following
delayed allocation write to the "hole", this would reclaim the same data
blocks again and results in fs corruption.

  # assmuing 4k block size ext4, with delalloc enabled
  # skip the first block and write to the second block
  xfs_io -fc "pwrite 4k 4k" -c "fsync" /mnt/ext4/testfile

  # converting to indirect-mapped file, which would move the data blocks
  # to the beginning of the file, but extent status cache still marks
  # that region as a hole
  chattr -e /mnt/ext4/testfile

  # delayed allocation writes to the "hole", reclaim the same data block
  # again, results in i_blocks corruption
  xfs_io -c "pwrite 0 4k" /mnt/ext4/testfile
  umount /mnt/ext4
  e2fsck -nf /dev/sda6
  ...
  Inode 53, i_blocks is 16, should be 8.  Fix? no
  ...

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

ext4: be more strict when migrating to non-extent based file

2015-08-03T16:29:00+00:00

commit d6f123a9297496ad0b6335fe881504c4b5b2a5e5 upstream.

Currently the check in ext4_ind_migrate() is not enough before doing the
real conversion:

a) delayed allocated extents could bypass the check on eh->eh_entries
   and eh->eh_depth

This can be demonstrated by this script

  xfs_io -fc "pwrite 0 4k" -c "pwrite 8k 4k" /mnt/ext4/testfile
  chattr -e /mnt/ext4/testfile

where testfile has two extents but still be converted to non-extent
based file format.

b) only extent length is checked but not the offset, which would result
   in data lose (delalloc) or fs corruption (nodelalloc), because
   non-extent based file only supports at most (12 + 2^10 + 2^20 + 2^30)
   blocks

This can be demostrated by

  xfs_io -fc "pwrite 5T 4k" /mnt/ext4/testfile
  chattr -e /mnt/ext4/testfile
  sync

If delalloc is enabled, dmesg prints
  EXT4-fs warning (device dm-4): ext4_block_to_path:105: block 1342177280 > max in inode 53
  EXT4-fs (dm-4): Delayed block allocation failed for inode 53 at logical offset 1342177280 with max blocks 1 with error 5
  EXT4-fs (dm-4): This should not happen!! Data will be lost

If delalloc is disabled, e2fsck -nf shows corruption
  Inode 53, i_size is 5497558142976, should be 4096.  Fix? no

Fix the two issues by

a) forcing all delayed allocation blocks to be allocated before checking
   eh->eh_depth and eh->eh_entries
b) limiting the last logical block of the extent is within direct map

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

ext4: fix reservation release on invalidatepage for delalloc fs

2015-08-03T16:29:00+00:00

commit 9705acd63b125dee8b15c705216d7186daea4625 upstream.

On delalloc enabled file system on invalidatepage operation
in ext4_da_page_release_reservation() we want to clear the delayed
buffer and remove the extent covering the delayed buffer from the extent
status tree.

However currently there is a bug where on the systems with page size >
block size we will always remove extents from the start of the page
regardless where the actual delayed buffers are positioned in the page.
This leads to the errors like this:

EXT4-fs warning (device loop0): ext4_da_release_space:1225:
ext4_da_release_space: ino 13, to_free 1 with only 0 reserved data
blocks

This however can cause data loss on writeback time if the file system is
in ENOSPC condition because we're releasing reservation for someones
else delayed buffer.

Fix this by only removing extents that corresponds to the part of the
page we want to invalidate.

This problem is reproducible by the following fio receipt (however I was
only able to reproduce it with fio-2.1 or older.

[global]
bs=8k
iodepth=1024
iodepth_batch=60
randrepeat=1
size=1m
directory=/mnt/test
numjobs=20
[job1]
ioengine=sync
bs=1k
direct=1
rw=randread
filename=file1:file2
[job2]
ioengine=libaio
rw=randwrite
direct=1
filename=file1:file2
[job3]
bs=1k
ioengine=posixaio
rw=randwrite
direct=1
filename=file1:file2
[job5]
bs=1k
ioengine=sync
rw=randread
filename=file1:file2
[job7]
ioengine=libaio
rw=randwrite
filename=file1:file2
[job8]
ioengine=posixaio
rw=randwrite
filename=file1:file2
[job10]
ioengine=mmap
rw=randwrite
bs=1k
filename=file1:file2
[job11]
ioengine=mmap
rw=randwrite
direct=1
filename=file1:file2

Signed-off-by: Lukas Czerner 
Signed-off-by: Theodore Ts'o 
Reviewed-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

ext4: avoid deadlocks in the writeback path by using sb_getblk_gfp

2015-08-03T16:29:00+00:00

commit c45653c341f5c8a0ce19c8f0ad4678640849cb86 upstream.

Switch ext4 to using sb_getblk_gfp with GFP_NOFS added to fix possible
deadlocks in the page writeback path.

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

ext4: fix fencepost error in lazytime optimization

2015-08-03T16:29:00+00:00

commit 0f0ff9a9f3fa2ec6f427603fd521d5f3a0b076d1 upstream.

Commit 8f4d8558391: "ext4: fix lazytime optimization" was not a
complete fix.  In the case where the inode number is a multiple of 16,
and we could still end up updating an inode with dirty timestamps
written to the wrong inode on disk.  Oops.

This can be easily reproduced by using generic/005 with a file system
with metadata_csum and lazytime enabled.

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

ext4: set lazytime on remount if MS_LAZYTIME is set by mount

2015-08-03T16:29:00+00:00

commit a2fd66d069d86d793e9d39d4079b96f46d13f237 upstream.

Newer versions of mount parse the lazytime feature and pass it to the
mount system call via the flags field in the mount system call,
removing the lazytime string from the mount options list.  So we need
to check for the presence of MS_LAZYTIME and set it in sb->s_flags in
order for this flag to be set on a remount.

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