linux.git/fs/nilfs2/sysfs.c, branch v5.13

nilfs2: fix memory leak in nilfs_sysfs_delete_device_group

2021-06-25T02:40:53+00:00

My local syzbot instance hit memory leak in nilfs2.  The problem was in
missing kobject_put() in nilfs_sysfs_delete_device_group().

kobject_del() does not call kobject_cleanup() for passed kobject and it
leads to leaking duped kobject name if kobject_put() was not called.

Fail log:

  BUG: memory leak
  unreferenced object 0xffff8880596171e0 (size 8):
  comm "syz-executor379", pid 8381, jiffies 4294980258 (age 21.100s)
  hex dump (first 8 bytes):
    6c 6f 6f 70 30 00 00 00                          loop0...
  backtrace:
     kstrdup+0x36/0x70 mm/util.c:60
     kstrdup_const+0x53/0x80 mm/util.c:83
     kvasprintf_const+0x108/0x190 lib/kasprintf.c:48
     kobject_set_name_vargs+0x56/0x150 lib/kobject.c:289
     kobject_add_varg lib/kobject.c:384 [inline]
     kobject_init_and_add+0xc9/0x160 lib/kobject.c:473
     nilfs_sysfs_create_device_group+0x150/0x800 fs/nilfs2/sysfs.c:999
     init_nilfs+0xe26/0x12b0 fs/nilfs2/the_nilfs.c:637

Link: https://lkml.kernel.org/r/20210612140559.20022-1-paskripkin@gmail.com
Fixes: da7141fb78db ("nilfs2: add /sys/fs/nilfs2/ group")
Signed-off-by: Pavel Skripkin 
Acked-by: Ryusuke Konishi 
Cc: Michael L. Semon 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: use a more common logging style

2020-08-12T17:58:01+00:00

Add macros for nilfs_(sb, fmt, ...) and convert the uses of
'nilfs_msg(sb, KERN_, ...)' to 'nilfs_(sb, ...)' so nilfs2
uses a logging style more like the typical kernel logging style.

Miscellanea:

o Realign arguments for these uses

Signed-off-by: Joe Perches 
Signed-off-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Link: http://lkml.kernel.org/r/1595860111-3920-4-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Linus Torvalds

nilfs2: convert to SPDX license tags

2018-09-04T23:45:02+00:00

Remove the verbose license text from NILFS2 files and replace them with
SPDX tags.  This does not change the license of any of the code.

Link: http://lkml.kernel.org/r/1535624528-5982-1-git-send-email-konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Ryusuke Konishi 
Reviewed-by: Andrew Morton 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: use time64_t internally

2018-02-07T02:32:45+00:00

The superblock and segment timestamps are used only internally in nilfs2
and can be read out using sysfs.

Since we are using the old 'get_seconds()' interface and store the data
as timestamps, the behavior differs slightly between 64-bit and 32-bit
kernels, the latter will show incorrect timestamps after 2038 in sysfs,
and presumably fail completely in 2106 as comparisons go wrong.

This changes nilfs2 to use time64_t with ktime_get_real_seconds() to
handle timestamps, making the behavior consistent and correct on both
32-bit and 64-bit machines.

The on-disk format already uses 64-bit timestamps, so nothing changes
there.

Link: http://lkml.kernel.org/r/20180122211050.1286441-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann 
Acked-by: Ryusuke Konishi 
Cc: Jens Axboe 
Cc: Ingo Molnar 
Cc: Jan Kara 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: fix misuse of a semaphore in sysfs code

2016-08-02T23:35:20+00:00

Variables ns_seg_seq, ns_segnum, ns_nextnum, ns_pseg_offset, ns_cno,
ns_ctime, ns_nongc_ctime, and ns_ndirtyblks, are protected by
ns_segctor_sem, but ns_sem is wrongly used by the nilfs sysfs code when
reading these variables.  This fixes the misuse and clarifies which
semaphore protects them in the comment of the_nilfs struct.

Link: http://lkml.kernel.org/r/1465825507-3407-2-git-send-email-konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: reduce bare use of printk() with nilfs_msg()

2016-08-02T23:35:17+00:00

Replace most use of printk() in nilfs2 implementation with nilfs_msg(),
and reduce the following checkpatch.pl warning:

  "WARNING: Prefer [subsystem eg: netdev]_crit([subsystem]dev, ...
   then dev_crit(dev, ... then pr_crit(...  to printk(KERN_CRIT ..."

This patch also fixes a minor checkpatch warning "WARNING: quoted string
split across lines" that often accompanies the prior warning, and amends
message format as needed.

Link: http://lkml.kernel.org/r/1464875891-5443-5-git-send-email-konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: avoid bare use of 'unsigned'

2016-05-24T00:04:14+00:00

This fixes checkpatch.pl warning "WARNING: Prefer 'unsigned int' to
bare use of 'unsigned'".

Link: http://lkml.kernel.org/r/1462886671-3521-5-git-send-email-konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: clean trailing semicolons in macros

2016-05-24T00:04:14+00:00

Remove trailing semicolons from macros, as suggested by checkpatch.pl.

Link: http://lkml.kernel.org/r/1461935747-10380-12-git-send-email-konishi.ryusuke@lab.ntt.co.jp
[konishi.ryusuke@lab.ntt.co.jp: fix style issues]
  Link: http://lkml.kernel.org/r/20160509.231703.1481729973362188932.konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: integrate sysfs support into driver

2014-08-08T22:57:21+00:00

This patch integrates creation of sysfs groups and
attributes into NILFS file system driver.

It was found the issue with nilfs_sysfs_{create/delete}_snapshot_group
functions by Michael L Semon  in the first
version of the patch:

  BUG: sleeping function called from invalid context at kernel/locking/mutex.c:579
  in_atomic(): 1, irqs_disabled(): 0, pid: 32676, name: umount.nilfs2
  2 locks held by umount.nilfs2/32676:
   #0:  (&type->s_umount_key#21){++++..}, at: [<790c18e2>] deactivate_super+0x37/0x58
   #1:  (&(&nilfs->ns_cptree_lock)->rlock){+.+...}, at: [<791bf659>] nilfs_put_root+0x23/0x5a
  Preemption disabled at:[<791bf659>] nilfs_put_root+0x23/0x5a

  CPU: 0 PID: 32676 Comm: umount.nilfs2 Not tainted 3.14.0+ #2
  Hardware name: Dell Computer Corporation Dimension 2350/07W080, BIOS A01 12/17/2002
  Call Trace:
    dump_stack+0x4b/0x75
    __might_sleep+0x111/0x16f
    mutex_lock_nested+0x1e/0x3ad
    kernfs_remove+0x12/0x26
    sysfs_remove_dir+0x3d/0x62
    kobject_del+0x13/0x38
    nilfs_sysfs_delete_snapshot_group+0xb/0xd
    nilfs_put_root+0x2a/0x5a
    nilfs_detach_log_writer+0x1ab/0x2c1
    nilfs_put_super+0x13/0x68
    generic_shutdown_super+0x60/0xd1
    kill_block_super+0x1d/0x60
    deactivate_locked_super+0x22/0x3f
    deactivate_super+0x3e/0x58
    mntput_no_expire+0xe2/0x141
    SyS_oldumount+0x70/0xa5
    syscall_call+0x7/0xb

The reason of the issue was placement of
nilfs_sysfs_{create/delete}_snapshot_group() call under
nilfs->ns_cptree_lock protection.  But this protection is unnecessary and
wrong solution.  The second version of the patch fixes this issue.

[fengguang.wu@intel.com: nilfs_sysfs_create_mounted_snapshots_group can be static]
Reported-by: Michael L. Semon 
Signed-off-by: Vyacheslav Dubeyko 
Cc: Vyacheslav Dubeyko 
Cc: Ryusuke Konishi 
Tested-by: Michael L. Semon 
Signed-off-by: Fengguang Wu 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: add /sys/fs/nilfs2//mounted_snapshots/ group

2014-08-08T22:57:21+00:00

This patch adds creation of  group for every mounted
snapshot in /sys/fs/nilfs2//mounted_snapshots group.

The group contains details about mounted snapshot:
(1) inodes_count - show number of inodes for snapshot.
(2) blocks_count - show number of blocks for snapshot.

Signed-off-by: Vyacheslav Dubeyko 
Cc: Vyacheslav Dubeyko 
Cc: Ryusuke Konishi 
Cc: Michael L. Semon 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds