usbip: vudc: fix NULL deref in vep_dequeue()
Summary
| CVE | CVE-2026-64331 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-25 10:17:14 UTC |
| Updated | 2026-07-25 10:17:14 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: usbip: vudc: fix NULL deref in vep_dequeue() vep_alloc_request() wasn't initializing vrequest->udc, so cancellations on the FunctionFS AIO path were arriving in vep_dequeue without a valid UDC reference. Since vrequest->udc is never actually properly used anywhere, we opt to remove it, and update vep_dequeue to obtain a reference to the udc with ep_to_vudc(), consistent with the other vep_ ops. AFAICT this bug has existed for ~10 years. Seems that nobody has really stressed the FunctionFS AIO path on usbip's vudc. I tested this fix in a QEMU aarch64 guest driving FunctionFS endpoints via AIO. Before the fix, running `usbip attach` from the host would cause the guest to oops with the following backtrace: Call trace: vep_dequeue+0x1c/0xe4 (P) usb_ep_dequeue+0x14/0x20 ffs_aio_cancel+0x24/0x34 __arm64_sys_io_cancel+0xb0/0x124 do_el0_svc+0x68/0x100 el0_svc+0x18/0x5c el0t_64_sync_handler+0x98/0xdc el0t_64_sync+0x154/0x158 |
Risk And Classification
EPSS: 0.001770000 probability, percentile 0.075090000 (date 2026-07-28)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected b6a0ca11186759ad7045d68a5447b1e89f658384 9858c91d9ee6a13c45311569039413729fc9b757 git | Not specified |
| CNA | Linux | Linux | affected b6a0ca11186759ad7045d68a5447b1e89f658384 1226293ec9bed3d4cc5b05eeeb811d315ca51652 git | Not specified |
| CNA | Linux | Linux | affected b6a0ca11186759ad7045d68a5447b1e89f658384 3750f75f29f99c0223601e2ee73ad084adec47bd git | Not specified |
| CNA | Linux | Linux | affected b6a0ca11186759ad7045d68a5447b1e89f658384 d0ebf9cc7c2ddf95a7cfc654b940bdacb7edde97 git | Not specified |
| CNA | Linux | Linux | affected b6a0ca11186759ad7045d68a5447b1e89f658384 0025276175fbbe0dcbf3f84d090b0adee769e9d9 git | Not specified |
| CNA | Linux | Linux | affected b6a0ca11186759ad7045d68a5447b1e89f658384 347b59e9f96719d89b6ef555d02a18ada1a5846f git | Not specified |
| CNA | Linux | Linux | affected b6a0ca11186759ad7045d68a5447b1e89f658384 0443e4416aa1ee97748d1ed904eaf3352c60045e git | Not specified |
| CNA | Linux | Linux | affected b6a0ca11186759ad7045d68a5447b1e89f658384 c5371e0b91b24159a3ebaa61e70b0980bcf03c0a git | Not specified |
| CNA | Linux | Linux | affected 4.7 | Not specified |
| CNA | Linux | Linux | unaffected 4.7 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.261 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.212 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.178 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.145 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.96 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.39 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1.4 7.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2-rc3 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/1226293ec9bed3d4cc5b05eeeb811d315ca51652 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/0025276175fbbe0dcbf3f84d090b0adee769e9d9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/9858c91d9ee6a13c45311569039413729fc9b757 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/c5371e0b91b24159a3ebaa61e70b0980bcf03c0a | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/3750f75f29f99c0223601e2ee73ad084adec47bd | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/0443e4416aa1ee97748d1ed904eaf3352c60045e | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/d0ebf9cc7c2ddf95a7cfc654b940bdacb7edde97 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/347b59e9f96719d89b6ef555d02a18ada1a5846f | 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.