linux-stable.git/fs/f2fs/debug.c, branch linux-3.16.y

f2fs: set ->owner for debugfs status file's file_operations

2017-03-16T02:26:25+00:00

commit 05e6ea2685c964db1e675a24a4f4e2adc22d2388 upstream.

The struct file_operations instance serving the f2fs/status debugfs file
lacks an initialization of its ->owner.

This means that although that file might have been opened, the f2fs module
can still get removed. Any further operation on that opened file, releasing
included,  will cause accesses to unmapped memory.

Indeed, Mike Marshall reported the following:

  BUG: unable to handle kernel paging request at ffffffffa0307430
  IP: [] full_proxy_release+0x24/0x90
  <...>
  Call Trace:
   [] __fput+0xdf/0x1d0
   [] ____fput+0xe/0x10
   [] task_work_run+0x8e/0xc0
   [] do_exit+0x2ae/0xae0
   [] ? __audit_syscall_entry+0xae/0x100
   [] ? syscall_trace_enter+0x1ca/0x310
   [] do_group_exit+0x44/0xc0
   [] SyS_exit_group+0x14/0x20
   [] do_syscall_64+0x61/0x150
   [] entry_SYSCALL64_slow_path+0x25/0x25
  <...>
  ---[ end trace f22ae883fa3ea6b8 ]---
  Fixing recursive fault but reboot is needed!

Fix this by initializing the f2fs/status file_operations' ->owner with
THIS_MODULE.

This will allow debugfs to grab a reference to the f2fs module upon any
open on that file, thus preventing it from getting removed.

Fixes: 902829aa0b72 ("f2fs: move proc files to debugfs")
Reported-by: Mike Marshall 
Reported-by: Martin Brandenburg 
Signed-off-by: Nicolai Stange 
Signed-off-by: Jaegeuk Kim 
Signed-off-by: Ben Hutchings

f2fs: remove unnecessary threshold

2014-03-20T13:10:09+00:00

The NM_WOUT_THRESHOLD is now obsolete since f2fs starts to control on a basis
of the memory footprint.

Signed-off-by: Jaegeuk Kim

f2fs: implement a lock-free stat_show

2014-02-24T07:00:41+00:00

The stat_show is just to show the current status of f2fs.
So, we can remove all the there-in locks.

Signed-off-by: Jaegeuk Kim

f2fs: show counts of checkpoint in status

2014-02-17T05:58:53+00:00

This patch shows the counts of checkpoint in f2fs' status.

Signed-off-by: Changman Lee 
Signed-off-by: Jaegeuk Kim

f2fs: introduce NODE_MAPPING for code consistency

2014-01-22T09:41:08+00:00

This patch adds NODE_MAPPING which is similar as META_MAPPING introduced by
Gu Zheng.

Cc: Gu Zheng 
Signed-off-by: Jaegeuk Kim

f2fs: add help function META_MAPPING

2014-01-22T09:41:07+00:00

Introduce help function META_MAPPING() to get the cache meta blocks'
address space.

Signed-off-by: Gu Zheng 
Signed-off-by: Jaegeuk Kim

f2fs: clean checkpatch warnings

2014-01-20T01:27:12+00:00

Fixed a variety of trivial checkpatch warnings.  The only delta should
be some minor formatting on log strings that were split / too long.

Signed-off-by: Chris Fries 
Signed-off-by: Jaegeuk Kim

f2fs: add delimiter to seperate name and value in debug phrase

2014-01-14T09:22:17+00:00

Support for f2fs-tools/tools/f2stat to monitor
/sys/kernel/debug/f2fs/status

Signed-off-by: Changman Lee 
Signed-off-by: Jaegeuk Kim

f2fs: add the number of inline_data files to status info

2014-01-06T07:42:20+00:00

This patch adds the number of inline_data files into the status information.
Note that the number is reset whenever the filesystem is newly mounted.

Signed-off-by: Jaegeuk Kim

f2fs: replace the debugfs_root with f2fs_debugfs_root

2013-12-23T01:18:05+00:00

This minor change for the naming conventions of debugfs_root
to avoid any possible conflicts to the other filesystem.

Signed-off-by: Younger Liu 
Cc: Younger Liu 
Cc: Jaegeuk Kim 
[Jaegeuk Kim: change the patch name]
Signed-off-by: Jaegeuk Kim