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Wang ShaoBo c10465f6d6 Bluetooth: fix use-after-free error in lock_sock_nested()
[ Upstream commit 1bff51ea59 ]

use-after-free error in lock_sock_nested is reported:

[  179.140137][ T3731] =====================================================
[  179.142675][ T3731] BUG: KMSAN: use-after-free in lock_sock_nested+0x280/0x2c0
[  179.145494][ T3731] CPU: 4 PID: 3731 Comm: kworker/4:2 Not tainted 5.12.0-rc6+ #54
[  179.148432][ T3731] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
[  179.151806][ T3731] Workqueue: events l2cap_chan_timeout
[  179.152730][ T3731] Call Trace:
[  179.153301][ T3731]  dump_stack+0x24c/0x2e0
[  179.154063][ T3731]  kmsan_report+0xfb/0x1e0
[  179.154855][ T3731]  __msan_warning+0x5c/0xa0
[  179.155579][ T3731]  lock_sock_nested+0x280/0x2c0
[  179.156436][ T3731]  ? kmsan_get_metadata+0x116/0x180
[  179.157257][ T3731]  l2cap_sock_teardown_cb+0xb8/0x890
[  179.158154][ T3731]  ? __msan_metadata_ptr_for_load_8+0x10/0x20
[  179.159141][ T3731]  ? kmsan_get_metadata+0x116/0x180
[  179.159994][ T3731]  ? kmsan_get_shadow_origin_ptr+0x84/0xb0
[  179.160959][ T3731]  ? l2cap_sock_recv_cb+0x420/0x420
[  179.161834][ T3731]  l2cap_chan_del+0x3e1/0x1d50
[  179.162608][ T3731]  ? kmsan_get_metadata+0x116/0x180
[  179.163435][ T3731]  ? kmsan_get_shadow_origin_ptr+0x84/0xb0
[  179.164406][ T3731]  l2cap_chan_close+0xeea/0x1050
[  179.165189][ T3731]  ? kmsan_internal_unpoison_shadow+0x42/0x70
[  179.166180][ T3731]  l2cap_chan_timeout+0x1da/0x590
[  179.167066][ T3731]  ? __msan_metadata_ptr_for_load_8+0x10/0x20
[  179.168023][ T3731]  ? l2cap_chan_create+0x560/0x560
[  179.168818][ T3731]  process_one_work+0x121d/0x1ff0
[  179.169598][ T3731]  worker_thread+0x121b/0x2370
[  179.170346][ T3731]  kthread+0x4ef/0x610
[  179.171010][ T3731]  ? process_one_work+0x1ff0/0x1ff0
[  179.171828][ T3731]  ? kthread_blkcg+0x110/0x110
[  179.172587][ T3731]  ret_from_fork+0x1f/0x30
[  179.173348][ T3731]
[  179.173752][ T3731] Uninit was created at:
[  179.174409][ T3731]  kmsan_internal_poison_shadow+0x5c/0xf0
[  179.175373][ T3731]  kmsan_slab_free+0x76/0xc0
[  179.176060][ T3731]  kfree+0x3a5/0x1180
[  179.176664][ T3731]  __sk_destruct+0x8af/0xb80
[  179.177375][ T3731]  __sk_free+0x812/0x8c0
[  179.178032][ T3731]  sk_free+0x97/0x130
[  179.178686][ T3731]  l2cap_sock_release+0x3d5/0x4d0
[  179.179457][ T3731]  sock_close+0x150/0x450
[  179.180117][ T3731]  __fput+0x6bd/0xf00
[  179.180787][ T3731]  ____fput+0x37/0x40
[  179.181481][ T3731]  task_work_run+0x140/0x280
[  179.182219][ T3731]  do_exit+0xe51/0x3e60
[  179.182930][ T3731]  do_group_exit+0x20e/0x450
[  179.183656][ T3731]  get_signal+0x2dfb/0x38f0
[  179.184344][ T3731]  arch_do_signal_or_restart+0xaa/0xe10
[  179.185266][ T3731]  exit_to_user_mode_prepare+0x2d2/0x560
[  179.186136][ T3731]  syscall_exit_to_user_mode+0x35/0x60
[  179.186984][ T3731]  do_syscall_64+0xc5/0x140
[  179.187681][ T3731]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  179.188604][ T3731] =====================================================

In our case, there are two Thread A and B:

Context: Thread A:              Context: Thread B:

l2cap_chan_timeout()            __se_sys_shutdown()
  l2cap_chan_close()              l2cap_sock_shutdown()
    l2cap_chan_del()                l2cap_chan_close()
      l2cap_sock_teardown_cb()        l2cap_sock_teardown_cb()

Once l2cap_sock_teardown_cb() excuted, this sock will be marked as SOCK_ZAPPED,
and can be treated as killable in l2cap_sock_kill() if sock_orphan() has
excuted, at this time we close sock through sock_close() which end to call
l2cap_sock_kill() like Thread C:

Context: Thread C:

sock_close()
  l2cap_sock_release()
    sock_orphan()
    l2cap_sock_kill()  #free sock if refcnt is 1

If C completed, Once A or B reaches l2cap_sock_teardown_cb() again,
use-after-free happened.

We should set chan->data to NULL if sock is destructed, for telling teardown
operation is not allowed in l2cap_sock_teardown_cb(), and also we should
avoid killing an already killed socket in l2cap_sock_close_cb().

Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-18 14:03:52 +01:00
arch powerpc/85xx: Fix oops when mpc85xx_smp_guts_ids node cannot be found 2021-11-18 14:03:48 +01:00
block block: schedule queue restart after BLK_STS_ZONE_RESOURCE 2021-11-18 14:03:43 +01:00
certs certs: Trigger creation of RSA module signing key if it's not an RSA key 2021-09-15 09:50:29 +02:00
crypto crypto: sm2 - fix a memory leak in sm2 2021-07-14 16:56:06 +02:00
Documentation xen/balloon: add late_initcall_sync() for initial ballooning done 2021-11-18 14:03:49 +01:00
drivers drm: panel-orientation-quirks: Add quirk for the Samsung Galaxy Book 10.6 2021-11-18 14:03:52 +01:00
fs quota: correct error number in free_dqentry() 2021-11-18 14:03:51 +01:00
include serial: core: Fix initializing and restoring termios speed 2021-11-18 14:03:49 +01:00
init sched/core: Initialize the idle task with preemption disabled 2021-07-14 16:55:50 +02:00
ipc ipc/mqueue, msg, sem: avoid relying on a stack reference past its expiry 2021-05-26 12:06:54 +02:00
kernel ring-buffer: Protect ring_buffer_reset() from reentrancy 2021-11-18 14:03:49 +01:00
lib treewide: Change list_sort to use const pointers 2021-09-30 10:11:04 +02:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm mm: khugepaged: skip huge page collapse for special files 2021-11-06 14:10:09 +01:00
net Bluetooth: fix use-after-free error in lock_sock_nested() 2021-11-18 14:03:52 +01:00
samples samples: bpf: Fix tracex7 error raised on the missing argument 2021-09-18 13:40:23 +02:00
scripts gcc-plugins/structleak: add makefile var for disabling structleak 2021-10-27 09:56:54 +02:00
security evm: mark evm_fixmode as __ro_after_init 2021-11-18 14:03:46 +01:00
sound ALSA: mixer: fix deadlock in snd_mixer_oss_set_volume 2021-11-18 14:03:49 +01:00
tools fcnal-test: kill hanging ping/nettest binaries on cleanup 2021-11-18 14:03:42 +01:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt KVM: do not shrink halt_poll_ns below grow_start 2021-10-09 14:40:58 +02:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig
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.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore kbuild: generate Module.symvers only when vmlinux exists 2021-05-19 10:12:59 +02:00
.mailmap mailmap: add two more addresses of Uwe Kleine-König 2020-12-06 10:19:07 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Jason Cooper to CREDITS 2020-11-30 10:20:34 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS f2fs: move ioctl interface definitions to separated file 2021-05-19 10:13:00 +02:00
Makefile Linux 5.10.79 2021-11-12 14:58:35 +01:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

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In order to build the documentation, use ``make htmldocs`` or
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    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
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