wifi: ath9k: hif_usb: don't dereference hif_dev after re-arming firmware request
Summary
| CVE | CVE-2026-68363 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-10 13:20:28 UTC |
| Updated | 2026-08-19 17:20:45 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: wifi: ath9k: hif_usb: don't dereference hif_dev after re-arming firmware request ath9k_hif_request_firmware() re-arms an asynchronous firmware load via request_firmware_nowait(), passing hif_dev as the completion context, and then still dereferences hif_dev: dev_info(&hif_dev->udev->dev, "ath9k_htc: Firmware %s requested\n", hif_dev->fw_name); The re-armed callback ath9k_hif_usb_firmware_cb() runs on the "events" workqueue and, when the firmware is missing, walks the retry chain into ath9k_hif_usb_firmware_fail() -> complete_all(&hif_dev->fw_done). That releases the wait_for_completion(&hif_dev->fw_done) in a concurrent ath9k_hif_usb_disconnect(), which then kfree()s hif_dev. The trailing dev_info() in the frame that re-armed the request can therefore read freed memory (hif_dev->udev, the first field of struct hif_device_usb): BUG: KASAN: slab-use-after-free in ath9k_hif_request_firmware Read of size 8 ... by task kworker/... ath9k_hif_request_firmware ath9k_hif_usb_firmware_cb drivers/net/wireless/ath/ath9k/hif_usb.c:1247 request_firmware_work_func Allocated by ...: ath9k_hif_usb_probe drivers/net/wireless/ath/ath9k/hif_usb.c Freed by ...: ath9k_hif_usb_disconnect -> kfree drivers/net/wireless/ath/ath9k/hif_usb.c The fw_done barrier only makes disconnect wait for the firmware chain to *terminate*; it does not protect the outer ath9k_hif_request_firmware() frame that re-armed the request and keeps touching hif_dev afterwards. Drop the post-request dev_info(): it is the only use of hif_dev after the async request is armed, and it is purely informational (the dev_err() on the failure path runs only when request_firmware_nowait() did not arm a callback, so hif_dev is still alive there). This was first reported by syzbot as a single, non-reproduced crash that was later auto-obsoleted, and was independently rediscovered by the reFuzz fuzzer, which produced a C reproducer (USB-gadget connect/disconnect of an ath9k_htc device whose firmware download fails). The vulnerable code is unchanged and still present in v7.1-rc6, where the slab-use-after-free reproduces under KASAN once the (sub-microsecond) race window is widened. |
Risk And Classification
EPSS: 0.001750000 probability, percentile 0.073400000 (date 2026-08-19)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected e904cf6fe23022cde4e0ea9d41601411a315a3dc 47ed81aaa7f94d9808f4719e78a760c2ec1e6c86 git | Not specified |
| CNA | Linux | Linux | affected e904cf6fe23022cde4e0ea9d41601411a315a3dc 48de0c6952192b0771fca468df4364d11ec74ad9 git | Not specified |
| CNA | Linux | Linux | affected e904cf6fe23022cde4e0ea9d41601411a315a3dc 063497cc9f320ab71a7a937c3bc0a23e630aefe2 git | Not specified |
| CNA | Linux | Linux | affected e904cf6fe23022cde4e0ea9d41601411a315a3dc 7f184ca38a90889f3f6665ff96748b95da39dbee git | Not specified |
| CNA | Linux | Linux | affected e904cf6fe23022cde4e0ea9d41601411a315a3dc 10b0ce629123a3737b4eda50188f73bb7be7b68b git | Not specified |
| CNA | Linux | Linux | affected e904cf6fe23022cde4e0ea9d41601411a315a3dc 48a69cedde7388294e4ea6fd804156cd62bc04fc git | Not specified |
| CNA | Linux | Linux | affected e904cf6fe23022cde4e0ea9d41601411a315a3dc 7c9046d92c4b9789c9d9d775e4fd5f34be64cb0a git | Not specified |
| CNA | Linux | Linux | affected e904cf6fe23022cde4e0ea9d41601411a315a3dc dad9f96945d77ecd4708f730c06ef54dcd8cc057 git | Not specified |
| CNA | Linux | Linux | affected 4.4 | Not specified |
| CNA | Linux | Linux | unaffected 4.4 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.265 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.216 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.183 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.148 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.101 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.42 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1.6 7.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/7f184ca38a90889f3f6665ff96748b95da39dbee | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/48a69cedde7388294e4ea6fd804156cd62bc04fc | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/47ed81aaa7f94d9808f4719e78a760c2ec1e6c86 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/063497cc9f320ab71a7a937c3bc0a23e630aefe2 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/48de0c6952192b0771fca468df4364d11ec74ad9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/dad9f96945d77ecd4708f730c06ef54dcd8cc057 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/7c9046d92c4b9789c9d9d775e4fd5f34be64cb0a | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/10b0ce629123a3737b4eda50188f73bb7be7b68b | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.