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 b40df5743e ("[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 4ce61d1c7a ("[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 4b5dd696f8 ("Bluetooth: Remove local_bh_disable() from
hci_sock.c") in 3.3-rc1 removed local_bh_disable().
Then, commit e305509e67 ("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: e305509e67 ("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>
These command do have variable length and the length can go up to 251,
so this changes the struct to not use a fixed size and then when
creating the PDU only the actual length of the data send to the
controller.
Fixes: a0fb3726ba ("Bluetooth: Use Set ext adv/scan rsp data if controller supports")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
During command status or command complete event, the controller may set
ncmd=0 indicating that it is not accepting any more commands. In such a
case, host holds off sending any more commands to the controller. If the
controller doesn't recover from such condition, host will wait forever,
until the user decides that the Bluetooth is broken and may power cycles
the Bluetooth.
This patch triggers the hardware error to reset the controller and
driver when it gets into such state as there is no other wat out.
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Manish Mandlik <mmandlik@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When an MGMT_EV_DEVICE_CONNECTED event is reported back to the user
space we will set the flags to tell if the established connection is
outbound or not. This is useful for the user space to log better metrics
and error messages.
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>
Reviewed-by: Alain Michaud <alainm@chromium.org>
Signed-off-by: Yu Liu <yudiliu@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Some controllers don't support the Simple Pairing Options feature that
can indicate the support for P-192 and P-256 public key validation.
However they might support the Microsoft vendor extension that can
indicate the validiation capability as well.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
The DISCOV_LE_FAST_ADV_INT_{MIN,MAX} contants are in msec, but then used
later on directly while it is suppose to be N * 0.625 ms according to
the Bluetooth Core specification.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
When drivers indicate support for AOSP vendor extension, initialize them
and read its capabilities.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
hci_chan can be created in 2 places: hci_loglink_complete_evt() if
it is an AMP hci_chan, or l2cap_conn_add() otherwise. In theory,
Only AMP hci_chan should be removed by a call to
hci_disconn_loglink_complete_evt(). However, the controller might mess
up, call that function, and destroy an hci_chan which is not initiated
by hci_loglink_complete_evt().
This patch adds a verification that the destroyed hci_chan must have
been init'd by hci_loglink_complete_evt().
Example crash call trace:
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xe3/0x144 lib/dump_stack.c:118
print_address_description+0x67/0x22a mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:354 [inline]
kasan_report mm/kasan/report.c:412 [inline]
kasan_report+0x251/0x28f mm/kasan/report.c:396
hci_send_acl+0x3b/0x56e net/bluetooth/hci_core.c:4072
l2cap_send_cmd+0x5af/0x5c2 net/bluetooth/l2cap_core.c:877
l2cap_send_move_chan_cfm_icid+0x8e/0xb1 net/bluetooth/l2cap_core.c:4661
l2cap_move_fail net/bluetooth/l2cap_core.c:5146 [inline]
l2cap_move_channel_rsp net/bluetooth/l2cap_core.c:5185 [inline]
l2cap_bredr_sig_cmd net/bluetooth/l2cap_core.c:5464 [inline]
l2cap_sig_channel net/bluetooth/l2cap_core.c:5799 [inline]
l2cap_recv_frame+0x1d12/0x51aa net/bluetooth/l2cap_core.c:7023
l2cap_recv_acldata+0x2ea/0x693 net/bluetooth/l2cap_core.c:7596
hci_acldata_packet net/bluetooth/hci_core.c:4606 [inline]
hci_rx_work+0x2bd/0x45e net/bluetooth/hci_core.c:4796
process_one_work+0x6f8/0xb50 kernel/workqueue.c:2175
worker_thread+0x4fc/0x670 kernel/workqueue.c:2321
kthread+0x2f0/0x304 kernel/kthread.c:253
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415
Allocated by task 38:
set_track mm/kasan/kasan.c:460 [inline]
kasan_kmalloc+0x8d/0x9a mm/kasan/kasan.c:553
kmem_cache_alloc_trace+0x102/0x129 mm/slub.c:2787
kmalloc include/linux/slab.h:515 [inline]
kzalloc include/linux/slab.h:709 [inline]
hci_chan_create+0x86/0x26d net/bluetooth/hci_conn.c:1674
l2cap_conn_add.part.0+0x1c/0x814 net/bluetooth/l2cap_core.c:7062
l2cap_conn_add net/bluetooth/l2cap_core.c:7059 [inline]
l2cap_connect_cfm+0x134/0x852 net/bluetooth/l2cap_core.c:7381
hci_connect_cfm+0x9d/0x122 include/net/bluetooth/hci_core.h:1404
hci_remote_ext_features_evt net/bluetooth/hci_event.c:4161 [inline]
hci_event_packet+0x463f/0x72fa net/bluetooth/hci_event.c:5981
hci_rx_work+0x197/0x45e net/bluetooth/hci_core.c:4791
process_one_work+0x6f8/0xb50 kernel/workqueue.c:2175
worker_thread+0x4fc/0x670 kernel/workqueue.c:2321
kthread+0x2f0/0x304 kernel/kthread.c:253
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415
Freed by task 1732:
set_track mm/kasan/kasan.c:460 [inline]
__kasan_slab_free mm/kasan/kasan.c:521 [inline]
__kasan_slab_free+0x106/0x128 mm/kasan/kasan.c:493
slab_free_hook mm/slub.c:1409 [inline]
slab_free_freelist_hook+0xaa/0xf6 mm/slub.c:1436
slab_free mm/slub.c:3009 [inline]
kfree+0x182/0x21e mm/slub.c:3972
hci_disconn_loglink_complete_evt net/bluetooth/hci_event.c:4891 [inline]
hci_event_packet+0x6a1c/0x72fa net/bluetooth/hci_event.c:6050
hci_rx_work+0x197/0x45e net/bluetooth/hci_core.c:4791
process_one_work+0x6f8/0xb50 kernel/workqueue.c:2175
worker_thread+0x4fc/0x670 kernel/workqueue.c:2321
kthread+0x2f0/0x304 kernel/kthread.c:253
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415
The buggy address belongs to the object at ffff8881d7af9180
which belongs to the cache kmalloc-128 of size 128
The buggy address is located 24 bytes inside of
128-byte region [ffff8881d7af9180, ffff8881d7af9200)
The buggy address belongs to the page:
page:ffffea00075ebe40 count:1 mapcount:0 mapping:ffff8881da403200 index:0x0
flags: 0x8000000000000200(slab)
raw: 8000000000000200 dead000000000100 dead000000000200 ffff8881da403200
raw: 0000000000000000 0000000080150015 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8881d7af9080: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
ffff8881d7af9100: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff8881d7af9180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8881d7af9200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8881d7af9280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
Signed-off-by: Archie Pusaka <apusaka@chromium.org>
Reported-by: syzbot+98228e7407314d2d4ba2@syzkaller.appspotmail.com
Reviewed-by: Alain Michaud <alainm@chromium.org>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When receiving L2CAP_CREDIT_BASED_CONNECTION_REQ the remote may request
more channels than allowed by the spec (10 octecs = 5 CIDs) so this
checks if the number of channels is bigger than the maximum allowed and
respond with an error.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
An issue was found, where if a bluetooth client requests a broadcast
advertisement with scan response data, it will not be properly
registered with the controller. This is because at the time that the
hci_cp_le_set_scan_param structure is created, the scan response will
not yet have been received since it comes in a second MGMT call. With
empty scan response, the request defaults to a non-scannable PDU type.
On some controllers, the subsequent scan response request will fail due
to incorrect PDU type, and others will succeed and not use the scan
response.
This fix allows the advertising parameters MGMT call to include a flag
to let the kernel know whether a scan response will be coming, so that
the correct PDU type is used in the first place. A bluetoothd change is
also incoming to take advantage of it.
To test this, I created a broadcast advertisement with scan response
data and registered it on the hatch chromebook. Without this change, the
request fails, and with it will succeed.
Reviewed-by: Alain Michaud <alainm@chromium.org>
Reviewed-by: Sonny Sasaka <sonnysasaka@chromium.org>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>
Signed-off-by: Daniel Winkler <danielwinkler@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
During suspend, there are a few scan enable and set event filter
commands that don't need to be sent unless there are actual BR/EDR
devices capable of waking the system. Check the HCI_PSCAN bit before
writing scan enable and use a new dev flag, HCI_EVENT_FILTER_CONFIGURED
to control whether to clear the event filter.
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Reviewed-by: Archie Pusaka <apusaka@chromium.org>
Reviewed-by: Alain Michaud <alainm@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If a peer device doesn't support eSCO 2M we should skip the params that
use it when setting up sync connection since they will always fail.
Signed-off-by: Yu Liu <yudiliu@google.com>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Some devices, e.g. the RTL8723BS bluetooth part, some USB attached devices,
completely drop from the bus on a system-suspend. These devices will
have their driver unbound and rebound on resume (when the dropping of
the bus gets detected) and will show up as a new HCI after resume.
These devices do not benefit from the suspend / resume handling work done
by the hci_suspend_notifier. At best this unnecessarily adds some time to
the suspend/resume time. But this may also actually cause problems, if the
code doing the driver unbinding runs after the pm-notifier then the
hci_suspend_notifier code will try to talk to a device which is now in
an uninitialized state.
This commit adds a new HCI_QUIRK_NO_SUSPEND_NOTIFIER quirk which allows
drivers to opt-out of the hci_suspend_notifier when they know beforehand
that their device will be fully re-initialized / reprobed on resume.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Bluetooth Core Specification v5.2, Vol. 3, Part A, section 1.4, table
1.1:
'Start Fragments always either begin with the first octet of the Basic
L2CAP header of a PDU or they have a length of zero (see [Vol 2] Part
B, Section 6.6.2).'
Apparently this was changed by the following errata:
https://www.bluetooth.org/tse/errata_view.cfm?errata_id=10216
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This adds logic to disable and reenable advertisement filters during
suspend and resume. After this patch, we would only receive packets from
devices in allow list during suspend.
Signed-off-by: Howard Chung <howardchung@google.com>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Enables advertising monitor offloading to the controller, if MSFT
extension is supported. The kernel won't adjust the monitor parameters
to match what the controller supports - that is the user space's
responsibility.
This patch only manages the addition of monitors. Monitor removal is
going to be handled by another patch.
Signed-off-by: Archie Pusaka <apusaka@chromium.org>
Reviewed-by: Manish Mandlik <mmandlik@chromium.org>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>
Reviewed-by: Yun-Hao Chung <howardchung@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
MSFT needs rssi parameter for monitoring advertisement packet,
therefore we should supply them from mgmt. This adds a new opcode
to add advertisement monitor with rssi parameters.
Signed-off-by: Archie Pusaka <apusaka@chromium.org>
Reviewed-by: Manish Mandlik <mmandlik@chromium.org>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>
Reviewed-by: Yun-Hao Chung <howardchung@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
For advertising, we wish to know the LE tx power capabilities of the
controller in userspace, so this patch edits the Security Info MGMT
command to be more generic, such that other various controller
capabilities can be included in the EIR data. This change also includes
the LE min and max tx power into this newly-named command.
The change was tested by manually verifying that the MGMT command
returns the tx power range as expected in userspace.
Reviewed-by: Sonny Sasaka <sonnysasaka@chromium.org>
Signed-off-by: Daniel Winkler <danielwinkler@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
