linux-toradex.git/fs/ext2/super.c, branch v3.15.10

Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

2014-04-08T00:59:17+00:00

Pull ext3 improvements, cleanups, reiserfs fix from Jan Kara:
 "various cleanups for ext2, ext3, udf, isofs, a documentation update
  for quota, and a fix of a race in reiserfs readdir implementation"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  reiserfs: fix race in readdir
  ext2: acl: remove unneeded include of linux/capability.h
  ext3: explicitly remove inode from orphan list after failed direct io
  fs/isofs/inode.c add __init to init_inodecache()
  ext3: Speedup WB_SYNC_ALL pass
  fs/quota/Kconfig: Update filesystems
  ext3: Update outdated comment before ext3_ordered_writepage()
  ext3: Update PF_MEMALLOC handling in ext3_write_inode()
  ext2/3: use prandom_u32() instead of get_random_bytes()
  ext3: remove an unneeded check in ext3_new_blocks()
  ext3: remove unneeded check in ext3_ordered_writepage()
  fs: Mark function as static in ext3/xattr_security.c
  fs: Mark function as static in ext3/dir.c
  fs: Mark function as static in ext2/xattr_security.c
  ext3: Add __init macro to init_inodecache
  ext2: Add __init macro to init_inodecache
  udf: Add __init macro to init_inodecache
  fs: udf: parse_options: blocksize check

fs: push sync_filesystem() down to the file system's remount_fs()

2014-03-13T14:14:33+00:00

Previously, the no-op "mount -o mount /dev/xxx" operation when the
file system is already mounted read-write causes an implied,
unconditional syncfs().  This seems pretty stupid, and it's certainly
documented or guaraunteed to do this, nor is it particularly useful,
except in the case where the file system was mounted rw and is getting
remounted read-only.

However, it's possible that there might be some file systems that are
actually depending on this behavior.  In most file systems, it's
probably fine to only call sync_filesystem() when transitioning from
read-write to read-only, and there are some file systems where this is
not needed at all (for example, for a pseudo-filesystem or something
like romfs).

Signed-off-by: "Theodore Ts'o" 
Cc: linux-fsdevel@vger.kernel.org
Cc: Christoph Hellwig 
Cc: Artem Bityutskiy 
Cc: Adrian Hunter 
Cc: Evgeniy Dushistov 
Cc: Jan Kara 
Cc: OGAWA Hirofumi 
Cc: Anders Larsen 
Cc: Phillip Lougher 
Cc: Kees Cook 
Cc: Mikulas Patocka 
Cc: Petr Vandrovec 
Cc: xfs@oss.sgi.com
Cc: linux-btrfs@vger.kernel.org
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Cc: codalist@coda.cs.cmu.edu
Cc: linux-ext4@vger.kernel.org
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: fuse-devel@lists.sourceforge.net
Cc: cluster-devel@redhat.com
Cc: linux-mtd@lists.infradead.org
Cc: jfs-discussion@lists.sourceforge.net
Cc: linux-nfs@vger.kernel.org
Cc: linux-nilfs@vger.kernel.org
Cc: linux-ntfs-dev@lists.sourceforge.net
Cc: ocfs2-devel@oss.oracle.com
Cc: reiserfs-devel@vger.kernel.org

ext2: Add __init macro to init_inodecache

2014-03-03T10:30:58+00:00

init_inodecache is only called by __init init_ext2_fs.

Signed-off-by: Fabian Frederick 
Signed-off-by: Jan Kara

ext2: Fix oops in ext2_get_block() called from ext2_quota_write()

2013-12-04T11:26:51+00:00

ext2_quota_write() doesn't properly setup bh it passes to
ext2_get_block() and thus we hit assertion BUG_ON(maxblocks == 0) in
ext2_get_blocks() (or we could actually ask for mapping arbitrary number
of blocks depending on whatever value was on stack).

Fix ext2_quota_write() to properly fill in number of blocks to map.

CC: stable@vger.kernel.org # >= 2.6.12
Reviewed-by: "Theodore Ts'o" 
Reviewed-by: Christoph Hellwig 
Reported-by: Christoph Hellwig 
Signed-off-by: Jan Kara

fs: Limit sys_mount to only request filesystem modules.

2013-03-04T03:36:31+00:00

Modify the request_module to prefix the file system type with "fs-"
and add aliases to all of the filesystems that can be built as modules
to match.

A common practice is to build all of the kernel code and leave code
that is not commonly needed as modules, with the result that many
users are exposed to any bug anywhere in the kernel.

Looking for filesystems with a fs- prefix limits the pool of possible
modules that can be loaded by mount to just filesystems trivially
making things safer with no real cost.

Using aliases means user space can control the policy of which
filesystem modules are auto-loaded by editing /etc/modprobe.d/*.conf
with blacklist and alias directives.  Allowing simple, safe,
well understood work-arounds to known problematic software.

This also addresses a rare but unfortunate problem where the filesystem
name is not the same as it's module name and module auto-loading
would not work.  While writing this patch I saw a handful of such
cases.  The most significant being autofs that lives in the module
autofs4.

This is relevant to user namespaces because we can reach the request
module in get_fs_type() without having any special permissions, and
people get uncomfortable when a user specified string (in this case
the filesystem type) goes all of the way to request_module.

After having looked at this issue I don't think there is any
particular reason to perform any filtering or permission checks beyond
making it clear in the module request that we want a filesystem
module.  The common pattern in the kernel is to call request_module()
without regards to the users permissions.  In general all a filesystem
module does once loaded is call register_filesystem() and go to sleep.
Which means there is not much attack surface exposed by loading a
filesytem module unless the filesystem is mounted.  In a user
namespace filesystems are not mounted unless .fs_flags = FS_USERNS_MOUNT,
which most filesystems do not set today.

Acked-by: Serge Hallyn 
Acked-by: Kees Cook 
Reported-by: Kees Cook 
Signed-off-by: "Eric W. Biederman"

Ext2: use unlikely to improve the efficiency of the kernel

2013-01-21T10:19:56+00:00

Because the function 'sb_getblk' seldomly fails to return
NULL value. It will be better to use unlikely to optimize it.

Signed-off-by: Wang shilong 
Signed-off-by: Jan Kara

ext2: fix return values on parse_options() failure

2012-10-09T21:23:53+00:00

parse_options() in ext2 should return 0 when parse the mount options fails.

Signed-off-by: Zhao Hongjiang 
Reviewed-by: Lukas Czerner 
Signed-off-by: Jan Kara

fs: push rcu_barrier() from deactivate_locked_super() to filesystems

2012-10-03T01:35:55+00:00

There's no reason to call rcu_barrier() on every
deactivate_locked_super().  We only need to make sure that all delayed rcu
free inodes are flushed before we destroy related cache.

Removing rcu_barrier() from deactivate_locked_super() affects some fast
paths.  E.g.  on my machine exit_group() of a last process in IPC
namespace takes 0.07538s.  rcu_barrier() takes 0.05188s of that time.

Signed-off-by: Kirill A. Shutemov 
Cc: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Al Viro

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2012-08-01T17:26:23+00:00

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
  ...

ext2: Implement freezing

2012-07-31T05:45:53+00:00

The only missing piece to make freezing work reliably with ext2 is to
stop iput() of unlinked inode from deleting the inode on frozen filesystem.
So add a necessary protection to ext2_evict_inode().

We also provide appropriate ->freeze_fs and ->unfreeze_fs functions.

Signed-off-by: Jan Kara 
Signed-off-by: Al Viro