[PATCH] Bluetooth: hci_sync: Serialize local codec list cleanup

[PATCH] Bluetooth: hci_sync: Serialize local codec list cleanup

[Chengfeng Ye]

hci_dev_close_sync() clears hdev->local_codecs after releasing hdev->lock.
Codec list additions and both traversals in sco_sock_getsockopt() use that
lock, but the close path does not. A close and BT_CODEC query can therefore
interleave as follows:

  hci_dev_close_sync()          sco_sock_getsockopt()
                                hci_dev_lock()
                                fetch codec entry
  hci_codec_list_clear()
    kfree(entry)
                                read entry->id

The reader then accesses an entry which the close path has freed. KASAN
reported:

  BUG: KASAN: slab-use-after-free in sco_sock_getsockopt+0xfa0/0xfe0
  Read of size 1 at addr ffff8881001c3450
  Call Trace:
   sco_sock_getsockopt+0xfa0/0xfe0
   do_sock_getsockopt+0x537/0x7b0
   __sys_getsockopt+0xf2/0x170
  Allocated by task 92:
   hci_codec_list_add.isra.0+0x2c/0x440
   hci_read_codec_capabilities+0x224/0x590
   hci_read_supported_codecs+0x2c2/0x640
  Freed by task 92:
   kfree+0x131/0x3c0
   hci_codec_list_clear+0xd8/0x160
   hci_dev_close_sync+0x92a/0xfa0

Take hdev->lock around the clear operation at its existing point in the
close path. This makes the clear wait for active readers and prevents a new
traversal until the list is empty without changing teardown ordering.

Fixes: b938790e7054 ("Bluetooth: hci_codec: Fix leaking content of local_codecs")
Cc: stable@vger.kernel.org
Signed-off-by: Chengfeng Ye <nicoyip.dev@gmail.com>
---
 net/bluetooth/hci_sync.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index b5897545d795..da748e14e5f3 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -5648,7 +5648,9 @@ int hci_dev_close_sync(struct hci_dev *hdev)
 	memset(hdev->eir, 0, sizeof(hdev->eir));
 	memset(hdev->dev_class, 0, sizeof(hdev->dev_class));
 	bacpy(&hdev->random_addr, BDADDR_ANY);
+	hci_dev_lock(hdev);
 	hci_codec_list_clear(&hdev->local_codecs);
+	hci_dev_unlock(hdev);
 
 	hci_dev_put(hdev);
 	return err;
-- 
2.43.0

RE: Bluetooth: hci_sync: Serialize local codec list cleanup

[bluez.test.bot]

[-- Attachment #1: Type: text/plain, Size: 2470 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=1149960

---Test result---

Test Summary:
CheckPatch                    PASS      0.72 seconds
VerifyFixes                   PASS      0.13 seconds
VerifySignedoff               PASS      0.13 seconds
GitLint                       PASS      0.32 seconds
SubjectPrefix                 PASS      0.12 seconds
BuildKernel                   PASS      26.27 seconds
CheckAllWarning               PASS      28.87 seconds
CheckSparse                   PASS      27.54 seconds
BuildKernel32                 PASS      26.00 seconds
CheckKernelLLVM               SKIP      0.00 seconds
TestRunnerSetup               PASS      471.98 seconds
TestRunner_l2cap-tester       PASS      78.99 seconds
TestRunner_iso-tester         PASS      108.23 seconds
TestRunner_bnep-tester        PASS      19.14 seconds
TestRunner_mgmt-tester        FAIL      220.33 seconds
TestRunner_rfcomm-tester      PASS      25.53 seconds
TestRunner_sco-tester         PASS      31.73 seconds
TestRunner_ioctl-tester       PASS      26.14 seconds
TestRunner_mesh-tester        FAIL      26.17 seconds
TestRunner_smp-tester         PASS      24.10 seconds
TestRunner_userchan-tester    PASS      20.12 seconds
TestRunner_6lowpan-tester     PASS      23.38 seconds
IncrementalBuild              PASS      24.45 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: 495 (98.8%), Failed: 2, Not Run: 4

Failed Test Cases
Read Exp Feature - Success                           Failed       0.252 seconds
LL Privacy - Remove Device 3 (Disable RL)            Failed       0.424 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    2.684 seconds
Mesh - Send cancel - 2                               Timed out    1.992 seconds


https://github.com/bluez/bluetooth-next/pull/631

---
Regards,
Linux Bluetooth

RE: Bluetooth: hci_sync: Serialize local codec list cleanup

[bluez.test.bot]

[-- Attachment #1: Type: text/plain, Size: 2235 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/series/1149960/

---Test result---

Test Summary:
CheckPatch                    PASS      0.68 seconds
VerifyFixes                   PASS      0.12 seconds
VerifySignedoff               PASS      0.10 seconds
GitLint                       PASS      0.30 seconds
SubjectPrefix                 PASS      0.10 seconds
BuildKernel                   PASS      27.24 seconds
CheckAllWarning               PASS      31.28 seconds
CheckSparse                   PASS      33.71 seconds
BuildKernel32                 PASS      27.91 seconds
CheckKernelLLVM               PASS      30.83 seconds
TestRunnerSetup               PASS      728.94 seconds
TestRunner_l2cap-tester       PASS      44.51 seconds
TestRunner_iso-tester         PASS      91.19 seconds
TestRunner_bnep-tester        PASS      12.16 seconds
TestRunner_mgmt-tester        FAIL      143.15 seconds
TestRunner_rfcomm-tester      PASS      16.12 seconds
TestRunner_sco-tester         PASS      21.19 seconds
TestRunner_ioctl-tester       PASS      17.26 seconds
TestRunner_mesh-tester        FAIL      18.16 seconds
TestRunner_smp-tester         PASS      14.84 seconds
TestRunner_userchan-tester    PASS      12.95 seconds
TestRunner_6lowpan-tester     PASS      15.19 seconds
IncrementalBuild              PASS      25.59 seconds

Details
##############################
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       0.140 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    2.356 seconds
Mesh - Send cancel - 2                               Timed out    1.996 seconds


https://github.com/bluez/bluetooth-next/pull/741

---
Regards,
Linux Bluetooth

Re: [PATCH] Bluetooth: hci_sync: Serialize local codec list cleanup

[patchwork-bot+bluetooth]

Hello:

This patch was applied to bluetooth/bluetooth-next.git (master)
by Luiz Augusto von Dentz <luiz.von.dentz@intel.com>:

On Sat, 22 Aug 2026 01:43:50 +0800 you wrote:
> hci_dev_close_sync() clears hdev->local_codecs after releasing hdev->lock.
> Codec list additions and both traversals in sco_sock_getsockopt() use that
> lock, but the close path does not. A close and BT_CODEC query can therefore
> interleave as follows:
> 
>   hci_dev_close_sync()          sco_sock_getsockopt()
>                                 hci_dev_lock()
>                                 fetch codec entry
>   hci_codec_list_clear()
>     kfree(entry)
>                                 read entry->id
> 
> [...]

Here is the summary with links:
  - Bluetooth: hci_sync: Serialize local codec list cleanup
    https://git.kernel.org/bluetooth/bluetooth-next/c/ee0662ba1e0a

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html