[PATCH bluetooth] Bluetooth: cancel devcoredump work during device teardown

[PATCH bluetooth] Bluetooth: cancel devcoredump work during device teardown

[Tristan Madani]

From: Tristan Madani <tristan@talencesecurity.com>

hci_devcd_setup() initializes dump_timeout and dump_rx work items
during device allocation, but hci_unregister_dev() does not cancel
them before the device is freed. If a devcoredump is in progress
when the device is unregistered, the dump_timeout delayed work timer
remains active. When it fires after hci_release_dev() frees the
hci_dev struct, it accesses freed memory.

Add hci_devcd_destroy() to disable dump work items and purge the
dump queue, called from hci_unregister_dev() alongside the existing
disable_work_sync() calls.

Fixes: 9695ef876fd1 ("Bluetooth: Add support for hci devcoredump")
Cc: stable@vger.kernel.org
Signed-off-by: Tristan Madani <tristan@talencesecurity.com>
---
 include/net/bluetooth/hci_core.h | 9 +++++++++
 net/bluetooth/hci_core.c         | 2 ++
 2 files changed, 11 insertions(+)

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 3df59849dcbea..5a60c3f94a462 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -1800,6 +1800,15 @@ static inline void hci_devcd_setup(struct hci_dev *hdev)
 #endif
 }
 
+static inline void hci_devcd_destroy(struct hci_dev *hdev)
+{
+#ifdef CONFIG_DEV_COREDUMP
+	disable_delayed_work_sync(&hdev->dump.dump_timeout);
+	disable_work_sync(&hdev->dump.dump_rx);
+	skb_queue_purge(&hdev->dump.dump_q);
+#endif
+}
+
 int hci_dev_open(__u16 dev);
 int hci_dev_close(__u16 dev);
 int hci_dev_do_close(struct hci_dev *hdev);
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 5ba9fe8261ec8..d4d559dabf422 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -2671,6 +2671,8 @@ void hci_unregister_dev(struct hci_dev *hdev)
 	disable_delayed_work_sync(&hdev->cmd_timer);
 	disable_delayed_work_sync(&hdev->ncmd_timer);
 
+	hci_devcd_destroy(hdev);
+
 	hci_cmd_sync_clear(hdev);
 
 	hci_unregister_suspend_notifier(hdev);
-- 
2.47.3

RE: Bluetooth: cancel devcoredump work during device teardown

[bluez.test.bot]

[-- Attachment #1: Type: text/plain, Size: 2389 bytes --]

This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=1146338

---Test result---

Test Summary:
CheckPatch                    PASS      0.96 seconds
VerifyFixes                   PASS      0.14 seconds
VerifySignedoff               PASS      0.13 seconds
GitLint                       PASS      0.38 seconds
SubjectPrefix                 PASS      0.13 seconds
BuildKernel                   PASS      26.69 seconds
CheckAllWarning               PASS      29.23 seconds
CheckSparse                   PASS      27.66 seconds
BuildKernel32                 PASS      25.10 seconds
CheckKernelLLVM               SKIP      0.00 seconds
TestRunnerSetup               PASS      480.86 seconds
TestRunner_l2cap-tester       PASS      71.48 seconds
TestRunner_iso-tester         PASS      99.99 seconds
TestRunner_bnep-tester        PASS      19.79 seconds
TestRunner_mgmt-tester        FAIL      223.16 seconds
TestRunner_rfcomm-tester      PASS      26.10 seconds
TestRunner_sco-tester         PASS      32.03 seconds
TestRunner_ioctl-tester       PASS      27.21 seconds
TestRunner_mesh-tester        FAIL      27.50 seconds
TestRunner_smp-tester         PASS      24.00 seconds
TestRunner_userchan-tester    PASS      20.60 seconds
TestRunner_6lowpan-tester     PASS      24.45 seconds
IncrementalBuild              PASS      24.51 seconds

Details
##############################
Test: CheckKernelLLVM - SKIP
Desc: Build kernel with LLVM + context analysis
Output:
Clang not found
##############################
Test: TestRunner_mgmt-tester - FAIL
Desc: Run mgmt-tester with test-runner
Output:
Total: 501, Passed: 496 (99.0%), Failed: 1, Not Run: 4

Failed Test Cases
Read Exp Feature - Success                           Failed       0.252 seconds
##############################
Test: TestRunner_mesh-tester - FAIL
Desc: Run mesh-tester with test-runner
Output:
Total: 10, Passed: 8 (80.0%), Failed: 2, Not Run: 0

Failed Test Cases
Mesh - Send cancel - 1                               Timed out    2.704 seconds
Mesh - Send cancel - 2                               Timed out    1.980 seconds


https://github.com/bluez/bluetooth-next/pull/585

---
Regards,
Linux Bluetooth

Re: [PATCH bluetooth] Bluetooth: cancel devcoredump work during device teardown

[Luiz Augusto von Dentz]

Hi Tristan,

On Fri, Aug 14, 2026 at 7:12 PM Tristan Madani <tristmd@gmail.com> wrote:
>
> From: Tristan Madani <tristan@talencesecurity.com>
>
> hci_devcd_setup() initializes dump_timeout and dump_rx work items
> during device allocation, but hci_unregister_dev() does not cancel
> them before the device is freed. If a devcoredump is in progress
> when the device is unregistered, the dump_timeout delayed work timer
> remains active. When it fires after hci_release_dev() frees the
> hci_dev struct, it accesses freed memory.
>
> Add hci_devcd_destroy() to disable dump work items and purge the
> dump queue, called from hci_unregister_dev() alongside the existing
> disable_work_sync() calls.
>
> Fixes: 9695ef876fd1 ("Bluetooth: Add support for hci devcoredump")
> Cc: stable@vger.kernel.org
> Signed-off-by: Tristan Madani <tristan@talencesecurity.com>
> ---
>  include/net/bluetooth/hci_core.h | 9 +++++++++
>  net/bluetooth/hci_core.c         | 2 ++
>  2 files changed, 11 insertions(+)
>
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index 3df59849dcbea..5a60c3f94a462 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -1800,6 +1800,15 @@ static inline void hci_devcd_setup(struct hci_dev *hdev)
>  #endif
>  }
>
> +static inline void hci_devcd_destroy(struct hci_dev *hdev)
> +{
> +#ifdef CONFIG_DEV_COREDUMP
> +       disable_delayed_work_sync(&hdev->dump.dump_timeout);
> +       disable_work_sync(&hdev->dump.dump_rx);
> +       skb_queue_purge(&hdev->dump.dump_q);
> +#endif
> +}
> +
>  int hci_dev_open(__u16 dev);
>  int hci_dev_close(__u16 dev);
>  int hci_dev_do_close(struct hci_dev *hdev);
> diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> index 5ba9fe8261ec8..d4d559dabf422 100644
> --- a/net/bluetooth/hci_core.c
> +++ b/net/bluetooth/hci_core.c
> @@ -2671,6 +2671,8 @@ void hci_unregister_dev(struct hci_dev *hdev)
>         disable_delayed_work_sync(&hdev->cmd_timer);
>         disable_delayed_work_sync(&hdev->ncmd_timer);
>
> +       hci_devcd_destroy(hdev);
> +
>         hci_cmd_sync_clear(hdev);
>
>         hci_unregister_suspend_notifier(hdev);
> --
> 2.47.3

Sashiko found 2 issues, both seem valid to me:

https://sashiko.dev/#/patchset/20260814182849.940976-1-ali%40iusegentoo.com

-- 
Luiz Augusto von Dentz