[PW_SID:1153084] Bluetooth: hci_core: Fix race condition during device registration - #660
[PW_SID:1153084] Bluetooth: hci_core: Fix race condition during device registration#660BluezTestBot wants to merge 1 commit into
Conversation
In hci_register_dev(), the power_on work item is queued to hdev->req_workqueue before initializing hdev->adv_monitors_idr and registering the MSFT extension via msft_register(). For devices marked with quirks such as HCI_QUIRK_RAW_DEVICE, the HCI_UNCONFIGURED flag is set on the device. When the power_on work item runs concurrently on another CPU, hci_power_on() detects that the device is unconfigured and immediately invokes hci_dev_do_close(), which calls msft_do_close(). Concurrently, msft_register() allocates the msft structure and exposes it to hdev->msft_data prior to calling mutex_init(&msft->filter_lock). If msft_do_close() executes while hdev->msft_data is already assigned but the mutex has not yet been initialized, mutex_lock(&msft->filter_lock) operates on an uninitialized mutex, triggering a DEBUG_LOCKS warning: DEBUG_LOCKS_WARN_ON(lock->magic != lock) WARNING: kernel/locking/mutex.c:625 at __mutex_lock_common kernel/locking/mutex.c:625 [inline] WARNING: kernel/locking/mutex.c:625 at __mutex_lock+0x12d8/0x1550 kernel/locking/mutex.c:821 ... Call Trace: <TASK> msft_do_close+0x308/0x7b0 net/bluetooth/msft.c:693 hci_dev_close_sync+0x86b/0x10a0 net/bluetooth/hci_sync.c:5522 hci_dev_do_close net/bluetooth/hci_core.c:499 [inline] hci_power_on+0x32c/0x750 net/bluetooth/hci_core.c:937 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0x92d/0xe10 kernel/workqueue.c:3486 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> Fix this by moving the queue_work() call in hci_register_dev() to after idr_init(&hdev->adv_monitors_idr) and msft_register(hdev) so that device structures and extensions are fully initialized before asynchronous tasks can access them. Additionally, assign hdev->msft_data in msft_register() only after mutex_init(&msft->filter_lock) has completed. Fixes: 9e14606 ("Bluetooth: msft: Extended monitor tracking by address filter") Assisted-by: Gemini:gemini-3.7-flash Gemini:gemini-3.1-pro-preview syzbot Reported-by: syzbot+14ce1b05b7d5a989abbe@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=14ce1b05b7d5a989abbe Link: https://syzkaller.appspot.com/ai_job?id=2bc9e8aa-ca6d-43e2-be2c-fd5d9f649d7e Signed-off-by: Aleksandr Nogikh <nogikh@google.com>
|
CheckPatch |
|
VerifyFixes |
|
VerifySignedoff |
|
GitLint |
|
SubjectPrefix |
|
BuildKernel |
|
CheckAllWarning |
|
CheckSparse |
|
BuildKernel32 |
|
CheckKernelLLVM |
|
TestRunnerSetup |
|
TestRunner_l2cap-tester |
|
TestRunner_iso-tester |
|
TestRunner_bnep-tester |
|
TestRunner_mgmt-tester |
|
TestRunner_rfcomm-tester |
|
TestRunner_sco-tester |
|
TestRunner_ioctl-tester |
|
TestRunner_mesh-tester |
|
TestRunner_smp-tester |
|
TestRunner_userchan-tester |
|
TestRunner_6lowpan-tester |
|
IncrementalBuild |
2 participants
From: Aleksandr Nogikh nogikh@google.com
In hci_register_dev(), the power_on work item is queued to
hdev->req_workqueue before initializing hdev->adv_monitors_idr and
registering the MSFT extension via msft_register(). For devices marked with
quirks such as HCI_QUIRK_RAW_DEVICE, the HCI_UNCONFIGURED flag is set on
the device. When the power_on work item runs concurrently on another CPU,
hci_power_on() detects that the device is unconfigured and immediately
invokes hci_dev_do_close(), which calls msft_do_close().
Concurrently, msft_register() allocates the msft structure and exposes it
to hdev->msft_data prior to calling mutex_init(&msft->filter_lock). If
msft_do_close() executes while hdev->msft_data is already assigned but the
mutex has not yet been initialized, mutex_lock(&msft->filter_lock) operates
on an uninitialized mutex, triggering a DEBUG_LOCKS warning:
DEBUG_LOCKS_WARN_ON(lock->magic != lock)
WARNING: kernel/locking/mutex.c:625 at __mutex_lock_common
kernel/locking/mutex.c:625 [inline]
WARNING: kernel/locking/mutex.c:625 at __mutex_lock+0x12d8/0x1550
kernel/locking/mutex.c:821
...
Call Trace:
msft_do_close+0x308/0x7b0 net/bluetooth/msft.c:693
hci_dev_close_sync+0x86b/0x10a0 net/bluetooth/hci_sync.c:5522
hci_dev_do_close net/bluetooth/hci_core.c:499 [inline]
hci_power_on+0x32c/0x750 net/bluetooth/hci_core.c:937
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0x92d/0xe10 kernel/workqueue.c:3486
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Fix this by moving the queue_work() call in hci_register_dev() to after
idr_init(&hdev->adv_monitors_idr) and msft_register(hdev) so that device
structures and extensions are fully initialized before asynchronous tasks
can access them. Additionally, assign hdev->msft_data in msft_register()
only after mutex_init(&msft->filter_lock) has completed.
Fixes: 9e14606 ("Bluetooth: msft: Extended monitor tracking by address filter")
Assisted-by: Gemini:gemini-3.7-flash Gemini:gemini-3.1-pro-preview syzbot
Reported-by: syzbot+14ce1b05b7d5a989abbe@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=14ce1b05b7d5a989abbe
Link: https://syzkaller.appspot.com/ai_job?id=2bc9e8aa-ca6d-43e2-be2c-fd5d9f649d7e
Signed-off-by: Aleksandr Nogikh nogikh@google.com
base-commit: 8d3ae59288f1e7d58d76558a6ee96d533bc5019f