linux-stable.git/fs/ext4/super.c, branch linux-3.6.y Linux kernel stable tree ext4: fix metadata checksum calculation for the superblock 2012-11-26T20:14:31+00:00 Theodore Ts'o tytso@mit.edu 2012-10-10T05:06:58+00:00 19dfc178ae0ed43e3cc8407f7876497a3ee5ba95 commit 06db49e68ae70cf16819b85a14057acb2820776a upstream. The function ext4_handle_dirty_super() was calculating the superblock on the wrong block data. As a result, when the superblock is modified while it is mounted (most commonly, when inodes are added or removed from the orphan list), the superblock checksum would be wrong. We didn't notice because the superblock *was* being correctly calculated in ext4_commit_super(), and this would get called when the file system was unmounted. So the problem only became obvious if the system crashed while the file system was mounted. Fix this by removing the poorly designed function signature for ext4_superblock_csum_set(); if it only took a single argument, the pointer to a struct superblock, the ambiguity which caused this mistake would have been impossible. Reported-by: George Spelvin <linux@horizon.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Tested-by: George Spelvin <linux@horizon.com> 
commit 06db49e68ae70cf16819b85a14057acb2820776a upstream.

The function ext4_handle_dirty_super() was calculating the superblock
on the wrong block data.  As a result, when the superblock is modified
while it is mounted (most commonly, when inodes are added or removed
from the orphan list), the superblock checksum would be wrong.  We
didn't notice because the superblock *was* being correctly calculated
in ext4_commit_super(), and this would get called when the file system
was unmounted.  So the problem only became obvious if the system
crashed while the file system was mounted.

Fix this by removing the poorly designed function signature for
ext4_superblock_csum_set(); if it only took a single argument, the
pointer to a struct superblock, the ambiguity which caused this
mistake would have been impossible.

Reported-by: George Spelvin <linux@horizon.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Tested-by: George Spelvin <linux@horizon.com>
ext4: fix crash when accessing /proc/mounts concurrently 2012-10-12T20:50:24+00:00 Herton Ronaldo Krzesinski herton.krzesinski@canonical.com 2012-09-24T02:49:12+00:00 2fdb1128f404ab026d2794de3bd604500edd444b commit 50df9fd55e4271e89a7adf3b1172083dd0ca199d upstream. The crash was caused by a variable being erronously declared static in token2str(). In addition to /proc/mounts, the problem can also be easily replicated by accessing /proc/fs/ext4/<partition>/options in parallel: $ cat /proc/fs/ext4/<partition>/options > options.txt ... and then running the following command in two different terminals: $ while diff /proc/fs/ext4/<partition>/options options.txt; do true; done This is also the cause of the following a crash while running xfstests #234, as reported in the following bug reports: https://bugs.launchpad.net/bugs/1053019 https://bugzilla.kernel.org/show_bug.cgi?id=47731 Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Brad Figg <brad.figg@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 50df9fd55e4271e89a7adf3b1172083dd0ca199d upstream.

The crash was caused by a variable being erronously declared static in
token2str().

In addition to /proc/mounts, the problem can also be easily replicated
by accessing /proc/fs/ext4/<partition>/options in parallel:

$ cat /proc/fs/ext4/<partition>/options > options.txt

... and then running the following command in two different terminals:

$ while diff /proc/fs/ext4/<partition>/options options.txt; do true; done

This is also the cause of the following a crash while running xfstests
#234, as reported in the following bug reports:

	https://bugs.launchpad.net/bugs/1053019
	https://bugzilla.kernel.org/show_bug.cgi?id=47731

Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Brad Figg <brad.figg@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 2012-08-17T15:04:47+00:00 Linus Torvalds torvalds@linux-foundation.org 2012-08-17T15:04:47+00:00 ef824bfba2cce6a75c7cd740f6ad80581e75a109 Pull ext4 bug fixes from Ted Ts'o: "The following are all bug fixes and regressions. The most notable are the ones which cause problems for ext4 on RAID --- a performance problem when mounting very large filesystems, and a kernel OOPS when doing an rm -rf on large directory hierarchies on fast devices." * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: fix kernel BUG on large-scale rm -rf commands ext4: fix long mount times on very big file systems ext4: don't call ext4_error while block group is locked ext4: avoid kmemcheck complaint from reading uninitialized memory ext4: make sure the journal sb is written in ext4_clear_journal_err() 
Pull ext4 bug fixes from Ted Ts'o:
 "The following are all bug fixes and regressions.  The most notable are
  the ones which cause problems for ext4 on RAID --- a performance
  problem when mounting very large filesystems, and a kernel OOPS when
  doing an rm -rf on large directory hierarchies on fast devices."

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix kernel BUG on large-scale rm -rf commands
  ext4: fix long mount times on very big file systems
  ext4: don't call ext4_error while block group is locked
  ext4: avoid kmemcheck complaint from reading uninitialized memory
  ext4: make sure the journal sb is written in ext4_clear_journal_err()
ext4: fix long mount times on very big file systems 2012-08-17T13:23:00+00:00 Theodore Ts'o tytso@mit.edu 2012-08-16T15:59:04+00:00 0548bbb85337e532ca2ed697c3e9b227ff2ed4b4 Commit 8aeb00ff85a: "ext4: fix overhead calculation used by ext4_statfs()" introduced a O(n**2) calculation which makes very large file systems take forever to mount. Fix this with an optimization for non-bigalloc file systems. (For bigalloc file systems the overhead needs to be set in the the superblock.) Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org 
Commit 8aeb00ff85a: "ext4: fix overhead calculation used by
ext4_statfs()" introduced a O(n**2) calculation which makes very large
file systems take forever to mount.  Fix this with an optimization for
non-bigalloc file systems.  (For bigalloc file systems the overhead
needs to be set in the the superblock.)

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
ext4: avoid kmemcheck complaint from reading uninitialized memory 2012-08-06T03:28:16+00:00 Theodore Ts'o tytso@mit.edu 2012-08-06T03:28:16+00:00 7e731bc9a12339f344cddf82166b82633d99dd86 Commit 03179fe923 introduced a kmemcheck complaint in ext4_da_get_block_prep() because we save and restore ei->i_da_metadata_calc_last_lblock even though it is left uninitialized in the case where i_da_metadata_calc_len is zero. This doesn't hurt anything, but silencing the kmemcheck complaint makes it easier for people to find real bugs. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=45631 (which is marked as a regression). Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org 
Commit 03179fe923 introduced a kmemcheck complaint in
ext4_da_get_block_prep() because we save and restore
ei->i_da_metadata_calc_last_lblock even though it is left
uninitialized in the case where i_da_metadata_calc_len is zero.

This doesn't hurt anything, but silencing the kmemcheck complaint
makes it easier for people to find real bugs.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=45631
(which is marked as a regression).

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
ext4: make sure the journal sb is written in ext4_clear_journal_err() 2012-08-05T23:04:57+00:00 Theodore Ts'o tytso@mit.edu 2012-08-05T23:04:57+00:00 d796c52ef0b71a988364f6109aeb63d79c5b116b After we transfer set the EXT4_ERROR_FS bit in the file system superblock, it's not enough to call jbd2_journal_clear_err() to clear the error indication from journal superblock --- we need to call jbd2_journal_update_sb_errno() as well. Otherwise, when the root file system is mounted read-only, the journal is replayed, and the error indicator is transferred to the superblock --- but the s_errno field in the jbd2 superblock is left set (since although we cleared it in memory, we never flushed it out to disk). This can end up confusing e2fsck. We should make e2fsck more robust in this case, but the kernel shouldn't be leaving things in this confused state, either. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org 
After we transfer set the EXT4_ERROR_FS bit in the file system
superblock, it's not enough to call jbd2_journal_clear_err() to clear
the error indication from journal superblock --- we need to call
jbd2_journal_update_sb_errno() as well.  Otherwise, when the root file
system is mounted read-only, the journal is replayed, and the error
indicator is transferred to the superblock --- but the s_errno field
in the jbd2 superblock is left set (since although we cleared it in
memory, we never flushed it out to disk).

This can end up confusing e2fsck.  We should make e2fsck more robust
in this case, but the kernel shouldn't be leaving things in this
confused state, either.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
ext4: nuke write_super from comments 2012-08-04T08:15:33+00:00 Artem Bityutskiy artem.bityutskiy@linux.intel.com 2012-07-25T15:12:03+00:00 7652bdfcb5888a389a7850ed19a4630e3a09cb9c The '->write_super' superblock method is gone, and this patch removes all the references to 'write_super' from ext3. Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
The '->write_super' superblock method is gone, and this patch removes all the
references to 'write_super' from ext3.

Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-08-01T17:26:23+00:00 Linus Torvalds torvalds@linux-foundation.org 2012-08-01T17:26:23+00:00 a0e881b7c189fa2bd76c024dbff91e79511c971d Pull second vfs pile from Al Viro: "The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the deadlock reproduced by xfstests 068), symlink and hardlink restriction patches, plus assorted cleanups and fixes. Note that another fsfreeze deadlock (emergency thaw one) is *not* dealt with - the series by Fernando conflicts a lot with Jan's, breaks userland ABI (FIFREEZE semantics gets changed) and trades the deadlock for massive vfsmount leak; this is going to be handled next cycle. There probably will be another pull request, but that stuff won't be in it." Fix up trivial conflicts due to unrelated changes next to each other in drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c} * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits) delousing target_core_file a bit Documentation: Correct s_umount state for freeze_fs/unfreeze_fs fs: Remove old freezing mechanism ext2: Implement freezing btrfs: Convert to new freezing mechanism nilfs2: Convert to new freezing mechanism ntfs: Convert to new freezing mechanism fuse: Convert to new freezing mechanism gfs2: Convert to new freezing mechanism ocfs2: Convert to new freezing mechanism xfs: Convert to new freezing code ext4: Convert to new freezing mechanism fs: Protect write paths by sb_start_write - sb_end_write fs: Skip atime update on frozen filesystem fs: Add freezing handling to mnt_want_write() / mnt_drop_write() fs: Improve filesystem freezing handling switch the protection of percpu_counter list to spinlock nfsd: Push mnt_want_write() outside of i_mutex btrfs: Push mnt_want_write() outside of i_mutex fat: Push mnt_want_write() outside of i_mutex ... 
Pull second vfs pile from Al Viro:
 "The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the
  deadlock reproduced by xfstests 068), symlink and hardlink restriction
  patches, plus assorted cleanups and fixes.

  Note that another fsfreeze deadlock (emergency thaw one) is *not*
  dealt with - the series by Fernando conflicts a lot with Jan's, breaks
  userland ABI (FIFREEZE semantics gets changed) and trades the deadlock
  for massive vfsmount leak; this is going to be handled next cycle.
  There probably will be another pull request, but that stuff won't be
  in it."

Fix up trivial conflicts due to unrelated changes next to each other in
drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c}

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
  delousing target_core_file a bit
  Documentation: Correct s_umount state for freeze_fs/unfreeze_fs
  fs: Remove old freezing mechanism
  ext2: Implement freezing
  btrfs: Convert to new freezing mechanism
  nilfs2: Convert to new freezing mechanism
  ntfs: Convert to new freezing mechanism
  fuse: Convert to new freezing mechanism
  gfs2: Convert to new freezing mechanism
  ocfs2: Convert to new freezing mechanism
  xfs: Convert to new freezing code
  ext4: Convert to new freezing mechanism
  fs: Protect write paths by sb_start_write - sb_end_write
  fs: Skip atime update on frozen filesystem
  fs: Add freezing handling to mnt_want_write() / mnt_drop_write()
  fs: Improve filesystem freezing handling
  switch the protection of percpu_counter list to spinlock
  nfsd: Push mnt_want_write() outside of i_mutex
  btrfs: Push mnt_want_write() outside of i_mutex
  fat: Push mnt_want_write() outside of i_mutex
  ...
ext4: Convert to new freezing mechanism 2012-07-31T05:45:48+00:00 Jan Kara jack@suse.cz 2012-06-12T14:20:38+00:00 8e8ad8a57c75f3bda2d03a4c4396a9a7024ad275 We remove most of frozen checks since upper layer takes care of blocking all writes. We have to handle protection in ext4_page_mkwrite() in a special way because we cannot use generic block_page_mkwrite(). Also we add a freeze protection to ext4_evict_inode() so that iput() of unlinked inode cannot modify a frozen filesystem (we cannot easily instrument ext4_journal_start() / ext4_journal_stop() with freeze protection because we are missing the superblock pointer in ext4_journal_stop() in nojournal mode). CC: linux-ext4@vger.kernel.org CC: "Theodore Ts'o" <tytso@mit.edu> BugLink: https://bugs.launchpad.net/bugs/897421 Tested-by: Kamal Mostafa <kamal@canonical.com> Tested-by: Peter M. Petrakis <peter.petrakis@canonical.com> Tested-by: Dann Frazier <dann.frazier@canonical.com> Tested-by: Massimo Morana <massimo.morana@canonical.com> Acked-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
We remove most of frozen checks since upper layer takes care of blocking all
writes. We have to handle protection in ext4_page_mkwrite() in a special way
because we cannot use generic block_page_mkwrite(). Also we add a freeze
protection to ext4_evict_inode() so that iput() of unlinked inode cannot modify
a frozen filesystem (we cannot easily instrument ext4_journal_start() /
ext4_journal_stop() with freeze protection because we are missing the
superblock pointer in ext4_journal_stop() in nojournal mode).

CC: linux-ext4@vger.kernel.org
CC: "Theodore Ts'o" <tytso@mit.edu>
BugLink: https://bugs.launchpad.net/bugs/897421
Tested-by: Kamal Mostafa <kamal@canonical.com>
Tested-by: Peter M. Petrakis <peter.petrakis@canonical.com>
Tested-by: Dann Frazier <dann.frazier@canonical.com>
Tested-by: Massimo Morana <massimo.morana@canonical.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 2012-07-28T03:52:25+00:00 Linus Torvalds torvalds@linux-foundation.org 2012-07-28T03:52:25+00:00 173f8654746c138a08f51a8a0db7747763a896a2 Pull ext4 updates from Ted Ts'o: "The usual collection of bug fixes and optimizations. Perhaps of greatest note is a speed up for parallel, non-allocating DIO writes, since we no longer take the i_mutex lock in that case. For bug fixes, we fix an incorrect overhead calculation which caused slightly incorrect results for df(1) and statfs(2). We also fixed bugs in the metadata checksum feature." * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (23 commits) ext4: undo ext4_calc_metadata_amount if we fail to claim space ext4: don't let i_reserved_meta_blocks go negative ext4: fix hole punch failure when depth is greater than 0 ext4: remove unnecessary argument from __ext4_handle_dirty_metadata() ext4: weed out ext4_write_super ext4: remove unnecessary superblock dirtying ext4: convert last user of ext4_mark_super_dirty() to ext4_handle_dirty_super() ext4: remove useless marking of superblock dirty ext4: fix ext4 mismerge back in January ext4: remove dynamic array size in ext4_chksum() ext4: remove unused variable in ext4_update_super() ext4: make quota as first class supported feature ext4: don't take the i_mutex lock when doing DIO overwrites ext4: add a new nolock flag in ext4_map_blocks ext4: split ext4_file_write into buffered IO and direct IO ext4: remove an unused statement in ext4_mb_get_buddy_page_lock() ext4: fix out-of-date comments in extents.c ext4: use s_csum_seed instead of i_csum_seed for xattr block ext4: use proper csum calculation in ext4_rename ext4: fix overhead calculation used by ext4_statfs() ... 
Pull ext4 updates from Ted Ts'o:
 "The usual collection of bug fixes and optimizations.  Perhaps of
  greatest note is a speed up for parallel, non-allocating DIO writes,
  since we no longer take the i_mutex lock in that case.

  For bug fixes, we fix an incorrect overhead calculation which caused
  slightly incorrect results for df(1) and statfs(2).  We also fixed
  bugs in the metadata checksum feature."

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (23 commits)
  ext4: undo ext4_calc_metadata_amount if we fail to claim space
  ext4: don't let i_reserved_meta_blocks go negative
  ext4: fix hole punch failure when depth is greater than 0
  ext4: remove unnecessary argument from __ext4_handle_dirty_metadata()
  ext4: weed out ext4_write_super
  ext4: remove unnecessary superblock dirtying
  ext4: convert last user of ext4_mark_super_dirty() to ext4_handle_dirty_super()
  ext4: remove useless marking of superblock dirty
  ext4: fix ext4 mismerge back in January
  ext4: remove dynamic array size in ext4_chksum()
  ext4: remove unused variable in ext4_update_super()
  ext4: make quota as first class supported feature
  ext4: don't take the i_mutex lock when doing DIO overwrites
  ext4: add a new nolock flag in ext4_map_blocks
  ext4: split ext4_file_write into buffered IO and direct IO
  ext4: remove an unused statement in ext4_mb_get_buddy_page_lock()
  ext4: fix out-of-date comments in extents.c
  ext4: use s_csum_seed instead of i_csum_seed for xattr block
  ext4: use proper csum calculation in ext4_rename
  ext4: fix overhead calculation used by ext4_statfs()
  ...