linux-stable.git/net/bluetooth, branch v4.4.288 Linux kernel stable tree Bluetooth: skip invalid hci_sync_conn_complete_evt 2021-09-22T09:41:25+00:00 Desmond Cheong Zhi Xi desmondcheongzx@gmail.com 2021-07-28T07:51:04+00:00 470f7a682dbd120b9a7b92715d0e57c9b98cc7cc [ Upstream commit 92fe24a7db751b80925214ede43f8d2be792ea7b ] Syzbot reported a corrupted list in kobject_add_internal [1]. This happens when multiple HCI_EV_SYNC_CONN_COMPLETE event packets with status 0 are sent for the same HCI connection. This causes us to register the device more than once which corrupts the kset list. As this is forbidden behavior, we add a check for whether we're trying to process the same HCI_EV_SYNC_CONN_COMPLETE event multiple times for one connection. If that's the case, the event is invalid, so we report an error that the device is misbehaving, and ignore the packet. Link: https://syzkaller.appspot.com/bug?extid=66264bf2fd0476be7e6c [1] Reported-by: syzbot+66264bf2fd0476be7e6c@syzkaller.appspotmail.com Tested-by: syzbot+66264bf2fd0476be7e6c@syzkaller.appspotmail.com Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 92fe24a7db751b80925214ede43f8d2be792ea7b ]

Syzbot reported a corrupted list in kobject_add_internal [1]. This
happens when multiple HCI_EV_SYNC_CONN_COMPLETE event packets with
status 0 are sent for the same HCI connection. This causes us to
register the device more than once which corrupts the kset list.

As this is forbidden behavior, we add a check for whether we're
trying to process the same HCI_EV_SYNC_CONN_COMPLETE event multiple
times for one connection. If that's the case, the event is invalid, so
we report an error that the device is misbehaving, and ignore the
packet.

Link: https://syzkaller.appspot.com/bug?extid=66264bf2fd0476be7e6c [1]
Reported-by: syzbot+66264bf2fd0476be7e6c@syzkaller.appspotmail.com
Tested-by: syzbot+66264bf2fd0476be7e6c@syzkaller.appspotmail.com
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bluetooth: add timeout sanity check to hci_inquiry 2021-09-22T09:41:21+00:00 Pavel Skripkin paskripkin@gmail.com 2021-08-19T15:15:21+00:00 90cc9527c8178f9f0a1deee2239734e958ac046a [ Upstream commit f41a4b2b5eb7872109723dab8ae1603bdd9d9ec1 ] Syzbot hit "task hung" bug in hci_req_sync(). The problem was in unreasonable huge inquiry timeout passed from userspace. Fix it by adding sanity check for timeout value to hci_inquiry(). Since hci_inquiry() is the only user of hci_req_sync() with user controlled timeout value, it makes sense to check timeout value in hci_inquiry() and don't touch hci_req_sync(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-and-tested-by: syzbot+be2baed593ea56c6a84c@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit f41a4b2b5eb7872109723dab8ae1603bdd9d9ec1 ]

Syzbot hit "task hung" bug in hci_req_sync(). The problem was in
unreasonable huge inquiry timeout passed from userspace.
Fix it by adding sanity check for timeout value to hci_inquiry().

Since hci_inquiry() is the only user of hci_req_sync() with user
controlled timeout value, it makes sense to check timeout value in
hci_inquiry() and don't touch hci_req_sync().

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-and-tested-by: syzbot+be2baed593ea56c6a84c@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bluetooth: Move shutdown callback before flushing tx and rx queue 2021-09-22T09:41:21+00:00 Kai-Heng Feng kai.heng.feng@canonical.com 2021-08-10T04:53:15+00:00 df5db051713fc377363457f83e4f37d36c0b7783 [ Upstream commit 0ea53674d07fb6db2dd7a7ec2fdc85a12eb246c2 ] Commit 0ea9fd001a14 ("Bluetooth: Shutdown controller after workqueues are flushed or cancelled") introduced a regression that makes mtkbtsdio driver stops working: [ 36.593956] Bluetooth: hci0: Firmware already downloaded [ 46.814613] Bluetooth: hci0: Execution of wmt command timed out [ 46.814619] Bluetooth: hci0: Failed to send wmt func ctrl (-110) The shutdown callback depends on the result of hdev->rx_work, so we should call it before flushing rx_work: -> btmtksdio_shutdown() -> mtk_hci_wmt_sync() -> __hci_cmd_send() -> wait for BTMTKSDIO_TX_WAIT_VND_EVT gets cleared -> btmtksdio_recv_event() -> hci_recv_frame() -> queue_work(hdev->workqueue, &hdev->rx_work) -> clears BTMTKSDIO_TX_WAIT_VND_EVT So move the shutdown callback before flushing TX/RX queue to resolve the issue. Reported-and-tested-by: Mattijs Korpershoek <mkorpershoek@baylibre.com> Tested-by: Hsin-Yi Wang <hsinyi@chromium.org> Cc: Guenter Roeck <linux@roeck-us.net> Fixes: 0ea9fd001a14 ("Bluetooth: Shutdown controller after workqueues are flushed or cancelled") Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 0ea53674d07fb6db2dd7a7ec2fdc85a12eb246c2 ]

Commit 0ea9fd001a14 ("Bluetooth: Shutdown controller after workqueues
are flushed or cancelled") introduced a regression that makes mtkbtsdio
driver stops working:
[   36.593956] Bluetooth: hci0: Firmware already downloaded
[   46.814613] Bluetooth: hci0: Execution of wmt command timed out
[   46.814619] Bluetooth: hci0: Failed to send wmt func ctrl (-110)

The shutdown callback depends on the result of hdev->rx_work, so we
should call it before flushing rx_work:
-> btmtksdio_shutdown()
 -> mtk_hci_wmt_sync()
  -> __hci_cmd_send()
   -> wait for BTMTKSDIO_TX_WAIT_VND_EVT gets cleared

-> btmtksdio_recv_event()
 -> hci_recv_frame()
  -> queue_work(hdev->workqueue, &hdev->rx_work)
   -> clears BTMTKSDIO_TX_WAIT_VND_EVT

So move the shutdown callback before flushing TX/RX queue to resolve the
issue.

Reported-and-tested-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Tested-by: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Fixes: 0ea9fd001a14 ("Bluetooth: Shutdown controller after workqueues are flushed or cancelled")
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bluetooth: fix repeated calls to sco_sock_kill 2021-09-22T09:41:20+00:00 Desmond Cheong Zhi Xi desmondcheongzx@gmail.com 2021-08-10T04:14:10+00:00 98ae477ed1540d3acbbf44d88ee237ad64275158 [ Upstream commit e1dee2c1de2b4dd00eb44004a4bda6326ed07b59 ] In commit 4e1a720d0312 ("Bluetooth: avoid killing an already killed socket"), a check was added to sco_sock_kill to skip killing a socket if the SOCK_DEAD flag was set. This was done after a trace for a use-after-free bug showed that the same sock pointer was being killed twice. Unfortunately, this check prevents sco_sock_kill from running on any socket. sco_sock_kill kills a socket only if it's zapped and orphaned, however sock_orphan announces that the socket is dead before detaching it. i.e., orphaned sockets have the SOCK_DEAD flag set. To fix this, we remove the check for SOCK_DEAD, and avoid repeated calls to sco_sock_kill by removing incorrect calls in: 1. sco_sock_timeout. The socket should not be killed on timeout as further processing is expected to be done. For example, sco_sock_connect sets the timer then waits for the socket to be connected or for an error to be returned. 2. sco_conn_del. This function should clean up resources for the connection, but the socket itself should be cleaned up in sco_sock_release. 3. sco_sock_close. Calls to sco_sock_close in sco_sock_cleanup_listen and sco_sock_release are followed by sco_sock_kill. Hence the duplicated call should be removed. Fixes: 4e1a720d0312 ("Bluetooth: avoid killing an already killed socket") Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e1dee2c1de2b4dd00eb44004a4bda6326ed07b59 ]

In commit 4e1a720d0312 ("Bluetooth: avoid killing an already killed
socket"), a check was added to sco_sock_kill to skip killing a socket
if the SOCK_DEAD flag was set.

This was done after a trace for a use-after-free bug showed that the
same sock pointer was being killed twice.

Unfortunately, this check prevents sco_sock_kill from running on any
socket. sco_sock_kill kills a socket only if it's zapped and orphaned,
however sock_orphan announces that the socket is dead before detaching
it. i.e., orphaned sockets have the SOCK_DEAD flag set.

To fix this, we remove the check for SOCK_DEAD, and avoid repeated
calls to sco_sock_kill by removing incorrect calls in:

1. sco_sock_timeout. The socket should not be killed on timeout as
further processing is expected to be done. For example,
sco_sock_connect sets the timer then waits for the socket to be
connected or for an error to be returned.

2. sco_conn_del. This function should clean up resources for the
connection, but the socket itself should be cleaned up in
sco_sock_release.

3. sco_sock_close. Calls to sco_sock_close in sco_sock_cleanup_listen
and sco_sock_release are followed by sco_sock_kill. Hence the
duplicated call should be removed.

Fixes: 4e1a720d0312 ("Bluetooth: avoid killing an already killed socket")
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bluetooth: increase BTNAMSIZ to 21 chars to fix potential buffer overflow 2021-09-22T09:41:20+00:00 Colin Ian King colin.king@canonical.com 2021-08-04T15:09:51+00:00 2fc4c1fb61cb58d16b50424173a3a58b42ce4044 [ Upstream commit 713baf3dae8f45dc8ada4ed2f5fdcbf94a5c274d ] An earlier commit replaced using batostr to using %pMR sprintf for the construction of session->name. Static analysis detected that this new method can use a total of 21 characters (including the trailing '\0') so we need to increase the BTNAMSIZ from 18 to 21 to fix potential buffer overflows. Addresses-Coverity: ("Out-of-bounds write") Fixes: fcb73338ed53 ("Bluetooth: Use %pMR in sprintf/seq_printf instead of batostr") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 713baf3dae8f45dc8ada4ed2f5fdcbf94a5c274d ]

An earlier commit replaced using batostr to using %pMR sprintf for the
construction of session->name. Static analysis detected that this new
method can use a total of 21 characters (including the trailing '\0')
so we need to increase the BTNAMSIZ from 18 to 21 to fix potential
buffer overflows.

Addresses-Coverity: ("Out-of-bounds write")
Fixes: fcb73338ed53 ("Bluetooth: Use %pMR in sprintf/seq_printf instead of batostr")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bluetooth: sco: prevent information leak in sco_conn_defer_accept() 2021-09-22T09:41:20+00:00 Dan Carpenter dan.carpenter@oracle.com 2021-06-25T15:00:09+00:00 071a6abebb0a76d8dc1cbc759c80a9ee05c7c9af [ Upstream commit 59da0b38bc2ea570ede23a3332ecb3e7574ce6b2 ] Smatch complains that some of these struct members are not initialized leading to a stack information disclosure: net/bluetooth/sco.c:778 sco_conn_defer_accept() warn: check that 'cp.retrans_effort' doesn't leak information This seems like a valid warning. I've added a default case to fix this issue. Fixes: 2f69a82acf6f ("Bluetooth: Use voice setting in deferred SCO connection request") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 59da0b38bc2ea570ede23a3332ecb3e7574ce6b2 ]

Smatch complains that some of these struct members are not initialized
leading to a stack information disclosure:

    net/bluetooth/sco.c:778 sco_conn_defer_accept() warn:
    check that 'cp.retrans_effort' doesn't leak information

This seems like a valid warning.  I've added a default case to fix
this issue.

Fixes: 2f69a82acf6f ("Bluetooth: Use voice setting in deferred SCO connection request")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bluetooth: hidp: use correct wait queue when removing ctrl_wait 2021-08-26T12:37:50+00:00 Ole Bjørn Midtbø omidtbo@cisco.com 2020-10-17T11:15:44+00:00 84805a23ac4310c0e9f4a400c090f42ad56a0b20 [ Upstream commit cca342d98bef68151a80b024f7bf5f388d1fbdea ] A different wait queue was used when removing ctrl_wait than when adding it. This effectively made the remove operation without locking compared to other operations on the wait queue ctrl_wait was part of. This caused issues like below where dead000000000100 is LIST_POISON1 and dead000000000200 is LIST_POISON2. list_add corruption. next->prev should be prev (ffffffc1b0a33a08), \ but was dead000000000200. (next=ffffffc03ac77de0). ------------[ cut here ]------------ CPU: 3 PID: 2138 Comm: bluetoothd Tainted: G O 4.4.238+ #9 ... ---[ end trace 0adc2158f0646eac ]--- Call trace: [<ffffffc000443f78>] __list_add+0x38/0xb0 [<ffffffc0000f0d04>] add_wait_queue+0x4c/0x68 [<ffffffc00020eecc>] __pollwait+0xec/0x100 [<ffffffc000d1556c>] bt_sock_poll+0x74/0x200 [<ffffffc000bdb8a8>] sock_poll+0x110/0x128 [<ffffffc000210378>] do_sys_poll+0x220/0x480 [<ffffffc0002106f0>] SyS_poll+0x80/0x138 [<ffffffc00008510c>] __sys_trace_return+0x0/0x4 Unable to handle kernel paging request at virtual address dead000000000100 ... CPU: 4 PID: 5387 Comm: kworker/u15:3 Tainted: G W O 4.4.238+ #9 ... Call trace: [<ffffffc0000f079c>] __wake_up_common+0x7c/0xa8 [<ffffffc0000f0818>] __wake_up+0x50/0x70 [<ffffffc000be11b0>] sock_def_wakeup+0x58/0x60 [<ffffffc000de5e10>] l2cap_sock_teardown_cb+0x200/0x224 [<ffffffc000d3f2ac>] l2cap_chan_del+0xa4/0x298 [<ffffffc000d45ea0>] l2cap_conn_del+0x118/0x198 [<ffffffc000d45f8c>] l2cap_disconn_cfm+0x6c/0x78 [<ffffffc000d29934>] hci_event_packet+0x564/0x2e30 [<ffffffc000d19b0c>] hci_rx_work+0x10c/0x360 [<ffffffc0000c2218>] process_one_work+0x268/0x460 [<ffffffc0000c2678>] worker_thread+0x268/0x480 [<ffffffc0000c94e0>] kthread+0x118/0x128 [<ffffffc000085070>] ret_from_fork+0x10/0x20 ---[ end trace 0adc2158f0646ead ]--- Signed-off-by: Ole Bjørn Midtbø <omidtbo@cisco.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit cca342d98bef68151a80b024f7bf5f388d1fbdea ]

A different wait queue was used when removing ctrl_wait than when adding
it. This effectively made the remove operation without locking compared
to other operations on the wait queue ctrl_wait was part of. This caused
issues like below where dead000000000100 is LIST_POISON1 and
dead000000000200 is LIST_POISON2.

 list_add corruption. next->prev should be prev (ffffffc1b0a33a08), \
	but was dead000000000200. (next=ffffffc03ac77de0).
 ------------[ cut here ]------------
 CPU: 3 PID: 2138 Comm: bluetoothd Tainted: G           O    4.4.238+ #9
 ...
 ---[ end trace 0adc2158f0646eac ]---
 Call trace:
 [<ffffffc000443f78>] __list_add+0x38/0xb0
 [<ffffffc0000f0d04>] add_wait_queue+0x4c/0x68
 [<ffffffc00020eecc>] __pollwait+0xec/0x100
 [<ffffffc000d1556c>] bt_sock_poll+0x74/0x200
 [<ffffffc000bdb8a8>] sock_poll+0x110/0x128
 [<ffffffc000210378>] do_sys_poll+0x220/0x480
 [<ffffffc0002106f0>] SyS_poll+0x80/0x138
 [<ffffffc00008510c>] __sys_trace_return+0x0/0x4

 Unable to handle kernel paging request at virtual address dead000000000100
 ...
 CPU: 4 PID: 5387 Comm: kworker/u15:3 Tainted: G        W  O    4.4.238+ #9
 ...
 Call trace:
  [<ffffffc0000f079c>] __wake_up_common+0x7c/0xa8
  [<ffffffc0000f0818>] __wake_up+0x50/0x70
  [<ffffffc000be11b0>] sock_def_wakeup+0x58/0x60
  [<ffffffc000de5e10>] l2cap_sock_teardown_cb+0x200/0x224
  [<ffffffc000d3f2ac>] l2cap_chan_del+0xa4/0x298
  [<ffffffc000d45ea0>] l2cap_conn_del+0x118/0x198
  [<ffffffc000d45f8c>] l2cap_disconn_cfm+0x6c/0x78
  [<ffffffc000d29934>] hci_event_packet+0x564/0x2e30
  [<ffffffc000d19b0c>] hci_rx_work+0x10c/0x360
  [<ffffffc0000c2218>] process_one_work+0x268/0x460
  [<ffffffc0000c2678>] worker_thread+0x268/0x480
  [<ffffffc0000c94e0>] kthread+0x118/0x128
  [<ffffffc000085070>] ret_from_fork+0x10/0x20
  ---[ end trace 0adc2158f0646ead ]---

Signed-off-by: Ole Bjørn Midtbø <omidtbo@cisco.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bluetooth: defer cleanup of resources in hci_unregister_dev() 2021-08-15T10:59:55+00:00 Tetsuo Handa penguin-kernel@i-love.sakura.ne.jp 2021-08-04T10:26:56+00:00 d6ef8bb00aa65eceb413fc165a55086459863e38 [ Upstream commit e04480920d1eec9c061841399aa6f35b6f987d8b ] syzbot is hitting might_sleep() warning at hci_sock_dev_event() due to calling lock_sock() with rw spinlock held [1]. It seems that history of this locking problem is a trial and error. Commit b40df5743ee8 ("[PATCH] bluetooth: fix socket locking in hci_sock_dev_event()") in 2.6.21-rc4 changed bh_lock_sock() to lock_sock() as an attempt to fix lockdep warning. Then, commit 4ce61d1c7a8e ("[BLUETOOTH]: Fix locking in hci_sock_dev_event().") in 2.6.22-rc2 changed lock_sock() to local_bh_disable() + bh_lock_sock_nested() as an attempt to fix the sleep in atomic context warning. Then, commit 4b5dd696f81b ("Bluetooth: Remove local_bh_disable() from hci_sock.c") in 3.3-rc1 removed local_bh_disable(). Then, commit e305509e678b ("Bluetooth: use correct lock to prevent UAF of hdev object") in 5.13-rc5 again changed bh_lock_sock_nested() to lock_sock() as an attempt to fix CVE-2021-3573. This difficulty comes from current implementation that hci_sock_dev_event(HCI_DEV_UNREG) is responsible for dropping all references from sockets because hci_unregister_dev() immediately reclaims resources as soon as returning from hci_sock_dev_event(HCI_DEV_UNREG). But the history suggests that hci_sock_dev_event(HCI_DEV_UNREG) was not doing what it should do. Therefore, instead of trying to detach sockets from device, let's accept not detaching sockets from device at hci_sock_dev_event(HCI_DEV_UNREG), by moving actual cleanup of resources from hci_unregister_dev() to hci_cleanup_dev() which is called by bt_host_release() when all references to this unregistered device (which is a kobject) are gone. Since hci_sock_dev_event(HCI_DEV_UNREG) no longer resets hci_pi(sk)->hdev, we need to check whether this device was unregistered and return an error based on HCI_UNREGISTER flag. There might be subtle behavioral difference in "monitor the hdev" functionality; please report if you found something went wrong due to this patch. Link: https://syzkaller.appspot.com/bug?extid=a5df189917e79d5e59c9 [1] Reported-by: syzbot <syzbot+a5df189917e79d5e59c9@syzkaller.appspotmail.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Fixes: e305509e678b ("Bluetooth: use correct lock to prevent UAF of hdev object") Acked-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e04480920d1eec9c061841399aa6f35b6f987d8b ]

syzbot is hitting might_sleep() warning at hci_sock_dev_event() due to
calling lock_sock() with rw spinlock held [1].

It seems that history of this locking problem is a trial and error.

Commit b40df5743ee8 ("[PATCH] bluetooth: fix socket locking in
hci_sock_dev_event()") in 2.6.21-rc4 changed bh_lock_sock() to
lock_sock() as an attempt to fix lockdep warning.

Then, commit 4ce61d1c7a8e ("[BLUETOOTH]: Fix locking in
hci_sock_dev_event().") in 2.6.22-rc2 changed lock_sock() to
local_bh_disable() + bh_lock_sock_nested() as an attempt to fix the
sleep in atomic context warning.

Then, commit 4b5dd696f81b ("Bluetooth: Remove local_bh_disable() from
hci_sock.c") in 3.3-rc1 removed local_bh_disable().

Then, commit e305509e678b ("Bluetooth: use correct lock to prevent UAF
of hdev object") in 5.13-rc5 again changed bh_lock_sock_nested() to
lock_sock() as an attempt to fix CVE-2021-3573.

This difficulty comes from current implementation that
hci_sock_dev_event(HCI_DEV_UNREG) is responsible for dropping all
references from sockets because hci_unregister_dev() immediately
reclaims resources as soon as returning from
hci_sock_dev_event(HCI_DEV_UNREG).

But the history suggests that hci_sock_dev_event(HCI_DEV_UNREG) was not
doing what it should do.

Therefore, instead of trying to detach sockets from device, let's accept
not detaching sockets from device at hci_sock_dev_event(HCI_DEV_UNREG),
by moving actual cleanup of resources from hci_unregister_dev() to
hci_cleanup_dev() which is called by bt_host_release() when all
references to this unregistered device (which is a kobject) are gone.

Since hci_sock_dev_event(HCI_DEV_UNREG) no longer resets
hci_pi(sk)->hdev, we need to check whether this device was unregistered
and return an error based on HCI_UNREGISTER flag.  There might be subtle
behavioral difference in "monitor the hdev" functionality; please report
if you found something went wrong due to this patch.

Link: https://syzkaller.appspot.com/bug?extid=a5df189917e79d5e59c9 [1]
Reported-by: syzbot <syzbot+a5df189917e79d5e59c9@syzkaller.appspotmail.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: e305509e678b ("Bluetooth: use correct lock to prevent UAF of hdev object")
Acked-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Revert "Bluetooth: Shutdown controller after workqueues are flushed or cancelled" 2021-08-08T06:37:47+00:00 Greg Kroah-Hartman gregkh@linuxfoundation.org 2021-08-05T18:58:57+00:00 d992022d65dbce6fc344ca6a263997205cc5a7a7 This reverts commit 5d16a8280078701fc03d6a0367c3251809743274 which is commit 0ea9fd001a14ebc294f112b0361a4e601551d508 upstream. It has been reported to have problems: https://lore.kernel.org/linux-bluetooth/8735ryk0o7.fsf@baylibre.com/ Reported-by: Guenter Roeck <linux@roeck-us.net> Cc: Kai-Heng Feng <kai.heng.feng@canonical.com> Cc: Marcel Holtmann <marcel@holtmann.org> Cc: Sasha Levin <sashal@kernel.org> Link: https://lore.kernel.org/r/efee3a58-a4d2-af22-0931-e81b877ab539@roeck-us.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
This reverts commit 5d16a8280078701fc03d6a0367c3251809743274 which is
commit 0ea9fd001a14ebc294f112b0361a4e601551d508 upstream.

It has been reported to have problems:
	https://lore.kernel.org/linux-bluetooth/8735ryk0o7.fsf@baylibre.com/

Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Sasha Levin <sashal@kernel.org>
Link: https://lore.kernel.org/r/efee3a58-a4d2-af22-0931-e81b877ab539@roeck-us.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bluetooth: Shutdown controller after workqueues are flushed or cancelled 2021-07-20T14:22:39+00:00 Kai-Heng Feng kai.heng.feng@canonical.com 2021-05-14T07:14:52+00:00 5d16a8280078701fc03d6a0367c3251809743274 [ Upstream commit 0ea9fd001a14ebc294f112b0361a4e601551d508 ] Rfkill block and unblock Intel USB Bluetooth [8087:0026] may make it stops working: [ 509.691509] Bluetooth: hci0: HCI reset during shutdown failed [ 514.897584] Bluetooth: hci0: MSFT filter_enable is already on [ 530.044751] usb 3-10: reset full-speed USB device number 5 using xhci_hcd [ 545.660350] usb 3-10: device descriptor read/64, error -110 [ 561.283530] usb 3-10: device descriptor read/64, error -110 [ 561.519682] usb 3-10: reset full-speed USB device number 5 using xhci_hcd [ 566.686650] Bluetooth: hci0: unexpected event for opcode 0x0500 [ 568.752452] Bluetooth: hci0: urb 0000000096cd309b failed to resubmit (113) [ 578.797955] Bluetooth: hci0: Failed to read MSFT supported features (-110) [ 586.286565] Bluetooth: hci0: urb 00000000c522f633 failed to resubmit (113) [ 596.215302] Bluetooth: hci0: Failed to read MSFT supported features (-110) Or kernel panics because other workqueues already freed skb: [ 2048.663763] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 2048.663775] #PF: supervisor read access in kernel mode [ 2048.663779] #PF: error_code(0x0000) - not-present page [ 2048.663782] PGD 0 P4D 0 [ 2048.663787] Oops: 0000 [#1] SMP NOPTI [ 2048.663793] CPU: 3 PID: 4491 Comm: rfkill Tainted: G W 5.13.0-rc1-next-20210510+ #20 [ 2048.663799] Hardware name: HP HP EliteBook 850 G8 Notebook PC/8846, BIOS T76 Ver. 01.01.04 12/02/2020 [ 2048.663801] RIP: 0010:__skb_ext_put+0x6/0x50 [ 2048.663814] Code: 8b 1b 48 85 db 75 db 5b 41 5c 5d c3 be 01 00 00 00 e8 de 13 c0 ff eb e7 be 02 00 00 00 e8 d2 13 c0 ff eb db 0f 1f 44 00 00 55 <8b> 07 48 89 e5 83 f8 01 74 14 b8 ff ff ff ff f0 0f c1 07 83 f8 01 [ 2048.663819] RSP: 0018:ffffc1d105b6fd80 EFLAGS: 00010286 [ 2048.663824] RAX: 0000000000000000 RBX: ffff9d9ac5649000 RCX: 0000000000000000 [ 2048.663827] RDX: ffffffffc0d1daf6 RSI: 0000000000000206 RDI: 0000000000000000 [ 2048.663830] RBP: ffffc1d105b6fd98 R08: 0000000000000001 R09: ffff9d9ace8ceac0 [ 2048.663834] R10: ffff9d9ace8ceac0 R11: 0000000000000001 R12: ffff9d9ac5649000 [ 2048.663838] R13: 0000000000000000 R14: 00007ffe0354d650 R15: 0000000000000000 [ 2048.663843] FS: 00007fe02ab19740(0000) GS:ffff9d9e5f8c0000(0000) knlGS:0000000000000000 [ 2048.663849] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2048.663853] CR2: 0000000000000000 CR3: 0000000111a52004 CR4: 0000000000770ee0 [ 2048.663856] PKRU: 55555554 [ 2048.663859] Call Trace: [ 2048.663865] ? skb_release_head_state+0x5e/0x80 [ 2048.663873] kfree_skb+0x2f/0xb0 [ 2048.663881] btusb_shutdown_intel_new+0x36/0x60 [btusb] [ 2048.663905] hci_dev_do_close+0x48c/0x5e0 [bluetooth] [ 2048.663954] ? __cond_resched+0x1a/0x50 [ 2048.663962] hci_rfkill_set_block+0x56/0xa0 [bluetooth] [ 2048.664007] rfkill_set_block+0x98/0x170 [ 2048.664016] rfkill_fop_write+0x136/0x1e0 [ 2048.664022] vfs_write+0xc7/0x260 [ 2048.664030] ksys_write+0xb1/0xe0 [ 2048.664035] ? exit_to_user_mode_prepare+0x37/0x1c0 [ 2048.664042] __x64_sys_write+0x1a/0x20 [ 2048.664048] do_syscall_64+0x40/0xb0 [ 2048.664055] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 2048.664060] RIP: 0033:0x7fe02ac23c27 [ 2048.664066] Code: 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 [ 2048.664070] RSP: 002b:00007ffe0354d638 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 2048.664075] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fe02ac23c27 [ 2048.664078] RDX: 0000000000000008 RSI: 00007ffe0354d650 RDI: 0000000000000003 [ 2048.664081] RBP: 0000000000000000 R08: 0000559b05998440 R09: 0000559b05998440 [ 2048.664084] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 [ 2048.664086] R13: 0000000000000000 R14: ffffffff00000000 R15: 00000000ffffffff So move the shutdown callback to a place where workqueues are either flushed or cancelled to resolve the issue. Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 0ea9fd001a14ebc294f112b0361a4e601551d508 ]

Rfkill block and unblock Intel USB Bluetooth [8087:0026] may make it
stops working:
[  509.691509] Bluetooth: hci0: HCI reset during shutdown failed
[  514.897584] Bluetooth: hci0: MSFT filter_enable is already on
[  530.044751] usb 3-10: reset full-speed USB device number 5 using xhci_hcd
[  545.660350] usb 3-10: device descriptor read/64, error -110
[  561.283530] usb 3-10: device descriptor read/64, error -110
[  561.519682] usb 3-10: reset full-speed USB device number 5 using xhci_hcd
[  566.686650] Bluetooth: hci0: unexpected event for opcode 0x0500
[  568.752452] Bluetooth: hci0: urb 0000000096cd309b failed to resubmit (113)
[  578.797955] Bluetooth: hci0: Failed to read MSFT supported features (-110)
[  586.286565] Bluetooth: hci0: urb 00000000c522f633 failed to resubmit (113)
[  596.215302] Bluetooth: hci0: Failed to read MSFT supported features (-110)

Or kernel panics because other workqueues already freed skb:
[ 2048.663763] BUG: kernel NULL pointer dereference, address: 0000000000000000
[ 2048.663775] #PF: supervisor read access in kernel mode
[ 2048.663779] #PF: error_code(0x0000) - not-present page
[ 2048.663782] PGD 0 P4D 0
[ 2048.663787] Oops: 0000 [#1] SMP NOPTI
[ 2048.663793] CPU: 3 PID: 4491 Comm: rfkill Tainted: G        W         5.13.0-rc1-next-20210510+ #20
[ 2048.663799] Hardware name: HP HP EliteBook 850 G8 Notebook PC/8846, BIOS T76 Ver. 01.01.04 12/02/2020
[ 2048.663801] RIP: 0010:__skb_ext_put+0x6/0x50
[ 2048.663814] Code: 8b 1b 48 85 db 75 db 5b 41 5c 5d c3 be 01 00 00 00 e8 de 13 c0 ff eb e7 be 02 00 00 00 e8 d2 13 c0 ff eb db 0f 1f 44 00 00 55 <8b> 07 48 89 e5 83 f8 01 74 14 b8 ff ff ff ff f0 0f c1
07 83 f8 01
[ 2048.663819] RSP: 0018:ffffc1d105b6fd80 EFLAGS: 00010286
[ 2048.663824] RAX: 0000000000000000 RBX: ffff9d9ac5649000 RCX: 0000000000000000
[ 2048.663827] RDX: ffffffffc0d1daf6 RSI: 0000000000000206 RDI: 0000000000000000
[ 2048.663830] RBP: ffffc1d105b6fd98 R08: 0000000000000001 R09: ffff9d9ace8ceac0
[ 2048.663834] R10: ffff9d9ace8ceac0 R11: 0000000000000001 R12: ffff9d9ac5649000
[ 2048.663838] R13: 0000000000000000 R14: 00007ffe0354d650 R15: 0000000000000000
[ 2048.663843] FS:  00007fe02ab19740(0000) GS:ffff9d9e5f8c0000(0000) knlGS:0000000000000000
[ 2048.663849] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2048.663853] CR2: 0000000000000000 CR3: 0000000111a52004 CR4: 0000000000770ee0
[ 2048.663856] PKRU: 55555554
[ 2048.663859] Call Trace:
[ 2048.663865]  ? skb_release_head_state+0x5e/0x80
[ 2048.663873]  kfree_skb+0x2f/0xb0
[ 2048.663881]  btusb_shutdown_intel_new+0x36/0x60 [btusb]
[ 2048.663905]  hci_dev_do_close+0x48c/0x5e0 [bluetooth]
[ 2048.663954]  ? __cond_resched+0x1a/0x50
[ 2048.663962]  hci_rfkill_set_block+0x56/0xa0 [bluetooth]
[ 2048.664007]  rfkill_set_block+0x98/0x170
[ 2048.664016]  rfkill_fop_write+0x136/0x1e0
[ 2048.664022]  vfs_write+0xc7/0x260
[ 2048.664030]  ksys_write+0xb1/0xe0
[ 2048.664035]  ? exit_to_user_mode_prepare+0x37/0x1c0
[ 2048.664042]  __x64_sys_write+0x1a/0x20
[ 2048.664048]  do_syscall_64+0x40/0xb0
[ 2048.664055]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 2048.664060] RIP: 0033:0x7fe02ac23c27
[ 2048.664066] Code: 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
[ 2048.664070] RSP: 002b:00007ffe0354d638 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 2048.664075] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fe02ac23c27
[ 2048.664078] RDX: 0000000000000008 RSI: 00007ffe0354d650 RDI: 0000000000000003
[ 2048.664081] RBP: 0000000000000000 R08: 0000559b05998440 R09: 0000559b05998440
[ 2048.664084] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
[ 2048.664086] R13: 0000000000000000 R14: ffffffff00000000 R15: 00000000ffffffff

So move the shutdown callback to a place where workqueues are either
flushed or cancelled to resolve the issue.

Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>