In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: btintel: serialize btintel_hw_error() with hci_req_sync_lock

btintel_hw_error() issues two __hci_cmd_sync() calls (HCI_OP_RESET
and Intel exception-info retrieval) without holding
hci_req_sync_lock(). This lets it race against
hci_dev_do_close() -> btintel_shutdown_combined(), which also runs
__hci_cmd_sync() under the same lock. When both paths manipulate
hdev->req_status/req_rsp concurrently, the close path may free the
response skb first, and the still-running hw_error path hits a
slab-use-after-free in kfree_skb().

Wrap the whole recovery sequence in hci_req_sync_lock/unlock so it
is serialized with every other synchronous HCI command issuer.

Below is the data race report and the kasan report:

BUG: data-race in __hci_cmd_sync_sk / btintel_shutdown_combined

read of hdev->req_rsp at net/bluetooth/hci_sync.c:199
by task kworker/u17:1/83:
__hci_cmd_sync_sk+0x12f2/0x1c30 net/bluetooth/hci_sync.c:200
__hci_cmd_sync+0x55/0x80 net/bluetooth/hci_sync.c:223
btintel_hw_error+0x114/0x670 drivers/bluetooth/btintel.c:254
hci_error_reset+0x348/0xa30 net/bluetooth/hci_core.c:1030

write/free by task ioctl/22580:
btintel_shutdown_combined+0xd0/0x360
drivers/bluetooth/btintel.c:3648
hci_dev_close_sync+0x9ae/0x2c10 net/bluetooth/hci_sync.c:5246
hci_dev_do_close+0x232/0x460 net/bluetooth/hci_core.c:526

BUG: KASAN: slab-use-after-free in
sk_skb_reason_drop+0x43/0x380 net/core/skbuff.c:1202
Read of size 4 at addr ffff888144a738dc
by task kworker/u17:1/83:
__hci_cmd_sync_sk+0x12f2/0x1c30 net/bluetooth/hci_sync.c:200
__hci_cmd_sync+0x55/0x80 net/bluetooth/hci_sync.c:223
btintel_hw_error+0x186/0x670 drivers/bluetooth/btintel.c:260

Project Subscriptions

Vendors Products
Linux Kernel Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 22 Apr 2026 14:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btintel: serialize btintel_hw_error() with hci_req_sync_lock btintel_hw_error() issues two __hci_cmd_sync() calls (HCI_OP_RESET and Intel exception-info retrieval) without holding hci_req_sync_lock(). This lets it race against hci_dev_do_close() -> btintel_shutdown_combined(), which also runs __hci_cmd_sync() under the same lock. When both paths manipulate hdev->req_status/req_rsp concurrently, the close path may free the response skb first, and the still-running hw_error path hits a slab-use-after-free in kfree_skb(). Wrap the whole recovery sequence in hci_req_sync_lock/unlock so it is serialized with every other synchronous HCI command issuer. Below is the data race report and the kasan report: BUG: data-race in __hci_cmd_sync_sk / btintel_shutdown_combined read of hdev->req_rsp at net/bluetooth/hci_sync.c:199 by task kworker/u17:1/83: __hci_cmd_sync_sk+0x12f2/0x1c30 net/bluetooth/hci_sync.c:200 __hci_cmd_sync+0x55/0x80 net/bluetooth/hci_sync.c:223 btintel_hw_error+0x114/0x670 drivers/bluetooth/btintel.c:254 hci_error_reset+0x348/0xa30 net/bluetooth/hci_core.c:1030 write/free by task ioctl/22580: btintel_shutdown_combined+0xd0/0x360 drivers/bluetooth/btintel.c:3648 hci_dev_close_sync+0x9ae/0x2c10 net/bluetooth/hci_sync.c:5246 hci_dev_do_close+0x232/0x460 net/bluetooth/hci_core.c:526 BUG: KASAN: slab-use-after-free in sk_skb_reason_drop+0x43/0x380 net/core/skbuff.c:1202 Read of size 4 at addr ffff888144a738dc by task kworker/u17:1/83: __hci_cmd_sync_sk+0x12f2/0x1c30 net/bluetooth/hci_sync.c:200 __hci_cmd_sync+0x55/0x80 net/bluetooth/hci_sync.c:223 btintel_hw_error+0x186/0x670 drivers/bluetooth/btintel.c:260
Title Bluetooth: btintel: serialize btintel_hw_error() with hci_req_sync_lock
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-04-22T13:54:21.071Z

Reserved: 2026-03-09T15:48:24.104Z

Link: CVE-2026-31500

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-04-22T14:16:48.427

Modified: 2026-04-22T14:16:48.427

Link: CVE-2026-31500

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.