linux-stable.git/fs/f2fs, branch linux-4.8.y

f2fs: fix overflow due to condition check order

2017-01-06T10:16:22+00:00

commit e87f7329bbd6760c2acc4f1eb423362b08851a71 upstream.

In the last ilen case, i was already increased, resulting in accessing out-
of-boundary entry of do_replace and blkaddr.
Fix to check ilen first to exit the loop.

Fixes: 2aa8fbb9693020 ("f2fs: refactor __exchange_data_block for speed up")
Signed-off-by: Jaegeuk Kim 
Signed-off-by: Greg Kroah-Hartman

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

2017-01-06T10:16:22+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: Greg Kroah-Hartman

Revert "f2fs: use percpu_counter for # of dirty pages in inode"

2017-01-06T10:16:22+00:00

commit 204706c7accfabb67b97eef9f9a28361b6201199 upstream.

This reverts commit 1beba1b3a953107c3ff5448ab4e4297db4619c76.

The perpcu_counter doesn't provide atomicity in single core and consume more
DRAM. That incurs fs_mark test failure due to ENOMEM.

Signed-off-by: Jaegeuk Kim 
Signed-off-by: Greg Kroah-Hartman

posix_acl: Clear SGID bit when setting file permissions

2016-10-31T11:02:08+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.

References: CVE-2016-7097
Reviewed-by: Christoph Hellwig 
Reviewed-by: Jeff Layton 
Signed-off-by: Jan Kara 
Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Juerg Haefliger 
Signed-off-by: Greg Kroah-Hartman

fscrypto: require write access to mount to set encryption policy

2016-09-10T05:18:57+00:00

Since setting an encryption policy requires writing metadata to the
filesystem, it should be guarded by mnt_want_write/mnt_drop_write.
Otherwise, a user could cause a write to a frozen or readonly
filesystem.  This was handled correctly by f2fs but not by ext4.  Make
fscrypt_process_policy() handle it rather than relying on the filesystem
to get it right.

Signed-off-by: Eric Biggers 
Cc: stable@vger.kernel.org # 4.1+; check fs/{ext4,f2fs}
Signed-off-by: Theodore Ts'o 
Acked-by: Jaegeuk Kim

f2fs: avoid potential deadlock in f2fs_move_file_range

2016-08-19T02:15:08+00:00

Thread A			Thread B
- inode_lock fileA
				- inode_lock fileB
				 - inode_lock fileA
 - inode_lock fileB

We may encounter above potential deadlock during moving file range in
concurrent scenario. This patch fixes the issue by using inode_trylock
instead.

Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: allow copying file range only in between regular files

2016-08-19T02:15:08+00:00

Only if two input files are regular files, we allow copying data in
range of them, otherwise, deny it.

Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

Revert "f2fs: move i_size_write in f2fs_write_end"

2016-08-19T02:15:08+00:00

This reverts commit a2ee0a300344a6da76186129b078113354fe13d2.

When testing with generic/032 of xfstest suit, failure message will be
reported as below:

generic/032 8s ... [failed, exit status 1] - output mismatch (see results/generic/032.out.bad)
    --- tests/generic/032.out	2015-01-11 16:52:27.643681072 +0800
    +++ results/generic/032.out.bad	2016-08-06 13:44:43.861330500 +0800
    @@ -1,5 +1,5 @@
     QA output created by 032
    -100 iterations
    -0000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
    -*
    -0100000
    +1: [768..775]: unwritten
    +Unwritten extents found!
    ...
    (Run 'diff -u tests/generic/032.out results/generic/032.out.bad'  to see the entire diff)
Ran: generic/032
Failures: generic/032
Failed 1 of 1 tests

In write_end(), we should update i_size of inode before unlock page,
otherwise, we will lose newly updated data in following race condition.

Thread A			Thread B
- write_end
 - unlock page
				- writepages
				 - lock_page
				  - writepage
				  if page is out-of-range of file size,
				  we will skip writting the page.
 - update i_size

Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

Revert "f2fs: use percpu_rw_semaphore"

2016-08-19T02:15:08+00:00

LKP reported -36.3% regression of fsmark.files_per_sec due to this patch.
I've confirmed that fxmark [1] has also slight regression for DWAL.

[1] https://github.com/sslab-gatech/fxmark

This reverts commit ec795418c41850056feb956534edf059dc1155d4.

Merge branch 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2016-08-06T13:49:02+00:00

Pull qstr constification updates from Al Viro:
 "Fairly self-contained bunch - surprising lot of places passes struct
  qstr * as an argument when const struct qstr * would suffice; it
  complicates analysis for no good reason.

  I'd prefer to feed that separately from the assorted fixes (those are
  in #for-linus and with somewhat trickier topology)"

* 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  qstr: constify instances in adfs
  qstr: constify instances in lustre
  qstr: constify instances in f2fs
  qstr: constify instances in ext2
  qstr: constify instances in vfat
  qstr: constify instances in procfs
  qstr: constify instances in fuse
  qstr constify instances in fs/dcache.c
  qstr: constify instances in nfs
  qstr: constify instances in ocfs2
  qstr: constify instances in autofs4
  qstr: constify instances in hfs
  qstr: constify instances in hfsplus
  qstr: constify instances in logfs
  qstr: constify dentry_init_security