CVE-2022-49169: f2fs: use spin_lock to avoid hang

CVE-2022-49169: f2fs: use spin_lock to avoid hang

[Greg Kroah-Hartman]

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

f2fs: use spin_lock to avoid hang

[14696.634553] task:cat             state:D stack:    0 pid:1613738 ppid:1613735 flags:0x00000004
[14696.638285] Call Trace:
[14696.639038]  <TASK>
[14696.640032]  __schedule+0x302/0x930
[14696.640969]  schedule+0x58/0xd0
[14696.641799]  schedule_preempt_disabled+0x18/0x30
[14696.642890]  __mutex_lock.constprop.0+0x2fb/0x4f0
[14696.644035]  ? mod_objcg_state+0x10c/0x310
[14696.645040]  ? obj_cgroup_charge+0xe1/0x170
[14696.646067]  __mutex_lock_slowpath+0x13/0x20
[14696.647126]  mutex_lock+0x34/0x40
[14696.648070]  stat_show+0x25/0x17c0 [f2fs]
[14696.649218]  seq_read_iter+0x120/0x4b0
[14696.650289]  ? aa_file_perm+0x12a/0x500
[14696.651357]  ? lru_cache_add+0x1c/0x20
[14696.652470]  seq_read+0xfd/0x140
[14696.653445]  full_proxy_read+0x5c/0x80
[14696.654535]  vfs_read+0xa0/0x1a0
[14696.655497]  ksys_read+0x67/0xe0
[14696.656502]  __x64_sys_read+0x1a/0x20
[14696.657580]  do_syscall_64+0x3b/0xc0
[14696.658671]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[14696.660068] RIP: 0033:0x7efe39df1cb2
[14696.661133] RSP: 002b:00007ffc8badd948 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[14696.662958] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007efe39df1cb2
[14696.664757] RDX: 0000000000020000 RSI: 00007efe399df000 RDI: 0000000000000003
[14696.666542] RBP: 00007efe399df000 R08: 00007efe399de010 R09: 00007efe399de010
[14696.668363] R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000000000
[14696.670155] R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000
[14696.671965]  </TASK>
[14696.672826] task:umount          state:D stack:    0 pid:1614985 ppid:1614984 flags:0x00004000
[14696.674930] Call Trace:
[14696.675903]  <TASK>
[14696.676780]  __schedule+0x302/0x930
[14696.677927]  schedule+0x58/0xd0
[14696.679019]  schedule_preempt_disabled+0x18/0x30
[14696.680412]  __mutex_lock.constprop.0+0x2fb/0x4f0
[14696.681783]  ? destroy_inode+0x65/0x80
[14696.683006]  __mutex_lock_slowpath+0x13/0x20
[14696.684305]  mutex_lock+0x34/0x40
[14696.685442]  f2fs_destroy_stats+0x1e/0x60 [f2fs]
[14696.686803]  f2fs_put_super+0x158/0x390 [f2fs]
[14696.688238]  generic_shutdown_super+0x7a/0x120
[14696.689621]  kill_block_super+0x27/0x50
[14696.690894]  kill_f2fs_super+0x7f/0x100 [f2fs]
[14696.692311]  deactivate_locked_super+0x35/0xa0
[14696.693698]  deactivate_super+0x40/0x50
[14696.694985]  cleanup_mnt+0x139/0x190
[14696.696209]  __cleanup_mnt+0x12/0x20
[14696.697390]  task_work_run+0x64/0xa0
[14696.698587]  exit_to_user_mode_prepare+0x1b7/0x1c0
[14696.700053]  syscall_exit_to_user_mode+0x27/0x50
[14696.701418]  do_syscall_64+0x48/0xc0
[14696.702630]  entry_SYSCALL_64_after_hwframe+0x44/0xae

The Linux kernel CVE team has assigned CVE-2022-49169 to this issue.


Affected and fixed versions
===========================

	Fixed in 5.15.33 with commit 2eff60346e7ae1a24cd868b8fdcf58e946e7dde1
	Fixed in 5.16.19 with commit 738886004bd2885ac2db0bc63b4874aa471ca87e
	Fixed in 5.17.2 with commit ec4187d45cc1c2d69fffeee5fa6aa4cb62477cfb
	Fixed in 5.18 with commit 98237fcda4a24e67b0a4498c17d5aa4ad4537bc7

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2022-49169
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	fs/f2fs/debug.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/2eff60346e7ae1a24cd868b8fdcf58e946e7dde1
	https://git.kernel.org/stable/c/738886004bd2885ac2db0bc63b4874aa471ca87e
	https://git.kernel.org/stable/c/ec4187d45cc1c2d69fffeee5fa6aa4cb62477cfb
	https://git.kernel.org/stable/c/98237fcda4a24e67b0a4498c17d5aa4ad4537bc7