linux-stable.git/fs/ext4, branch linux-3.12.y

ext4: check if in-inode xattr is corrupted in ext4_expand_extra_isize_ea()

2017-05-09T06:19:50+00:00

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().

[js] use EIO instead of undefined EFSCORRUPTED in 3.12

Signed-off-by: Theodore Ts'o 
Cc: Julia Lawall 
Signed-off-by: Jiri Slaby

ext4: fix inode checksum calculation problem if i_extra_size is small

2017-05-03T12:22:43+00:00

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 
Signed-off-by: Daeho Jeong 
Signed-off-by: Youngjin Gil 
Signed-off-by: Darrick J. Wong 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jiri Slaby

ext4: mark inode dirty after converting inline directory

2017-04-07T08:38:27+00:00

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: 3c47d54170b6a678875566b1b8d6dcf57904e49b
Signed-off-by: Eric Biggers 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jiri Slaby

ext4: return EROFS if device is r/o and journal replay is needed

2017-03-13T20:40:31+00:00

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 
Signed-off-by: Jiri Slaby

ext4: preserve the needs_recovery flag when the journal is aborted

2017-03-13T20:40:30+00:00

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 
Signed-off-by: Jiri Slaby

ext4: trim allocation requests to group size

2017-03-13T20:40:29+00:00

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" 
Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jiri Slaby

ext4: fix fencepost in s_first_meta_bg validation

2017-03-03T10:30:48+00:00

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 
Signed-off-by: Jiri Slaby

ext4: validate s_first_meta_bg at mount time

2017-03-03T10:29:32+00:00

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.

[js] use EXT4_HAS_INCOMPAT_FEATURE instead of new
     ext4_has_feature_meta_bg

Reported-by: Ralf Spenneberg 
Signed-off-by: Eryu Guan 
Signed-off-by: Theodore Ts'o 
Reviewed-by: Andreas Dilger 
Signed-off-by: Jiri Slaby

posix_acl: Clear SGID bit when setting file permissions

2017-01-27T10:15:59+00:00

commit 073931017b49d9458aa351605b43a7e34598caef upstream.

When file permissions are modified via chmod(2) and the user is not in
the owning group or capable of CAP_FSETID, the setgid bit is cleared in
inode_change_ok().  Setting a POSIX ACL via setxattr(2) sets the file
permissions as well as the new ACL, but doesn't clear the setgid bit in
a similar way; this allows to bypass the check in chmod(2).  Fix that.

Reviewed-by: Christoph Hellwig 
Reviewed-by: Jeff Layton 
Signed-off-by: Jan Kara 
Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Jiri Slaby

ext4: return -ENOMEM instead of success

2017-01-26T16:22:36+00:00

commit 578620f451f836389424833f1454eeeb2ffc9e9f upstream.

We should set the error code if kzalloc() fails.

Fixes: 67cf5b09a46f ("ext4: add the basic function for inline data support")
Signed-off-by: Dan Carpenter 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jiri Slaby