usb: chipidea: udc: fix DMA and SG cleanup in _ep_nuke()
Summary
| CVE | CVE-2026-43250 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-06 12:16:45 UTC |
| Updated | 2026-05-12 18:51:16 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: usb: chipidea: udc: fix DMA and SG cleanup in _ep_nuke() The ChipIdea UDC driver can encounter "not page aligned sg buffer" errors when a USB device is reconnected after being disconnected during an active transfer. This occurs because _ep_nuke() returns requests to the gadget layer without properly unmapping DMA buffers or cleaning up scatter-gather bounce buffers. Root cause: When a disconnect happens during a multi-segment DMA transfer, the request's num_mapped_sgs field and sgt.sgl pointer remain set with stale values. The request is returned to the gadget driver with status -ESHUTDOWN but still has active DMA state. If the gadget driver reuses this request on reconnect without reinitializing it, the stale DMA state causes _hardware_enqueue() to skip DMA mapping (seeing non-zero num_mapped_sgs) and attempt to use freed/invalid DMA addresses, leading to alignment errors and potential memory corruption. The normal completion path via _hardware_dequeue() properly calls usb_gadget_unmap_request_by_dev() and sglist_do_debounce() before returning the request. The _ep_nuke() path must do the same cleanup to ensure requests are returned in a clean, reusable state. Fix: Add DMA unmapping and bounce buffer cleanup to _ep_nuke() to mirror the cleanup sequence in _hardware_dequeue(): - Call usb_gadget_unmap_request_by_dev() if num_mapped_sgs is set - Call sglist_do_debounce() with copy=false if bounce buffer exists This ensures that when requests are returned due to endpoint shutdown, they don't retain stale DMA mappings. The 'false' parameter to sglist_do_debounce() prevents copying data back (appropriate for shutdown path where transfer was aborted). |
Risk And Classification
Primary CVSS: v3.1 7.8 HIGH from [email protected]
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Problem Types: CWE-787
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Operating System | Linux | Linux Kernel | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected aa69a8093ff985873cb44fe1157bd6db29a20fe4 1b72b834511d17f4d069d512f78671f3f210a2f1 git | Not specified |
| CNA | Linux | Linux | affected aa69a8093ff985873cb44fe1157bd6db29a20fe4 f4fbf2d4750d12ac8525d2efac1016fa0d84d4ec git | Not specified |
| CNA | Linux | Linux | affected aa69a8093ff985873cb44fe1157bd6db29a20fe4 e74c436f8568af1c60942469d0a2300b3ada3857 git | Not specified |
| CNA | Linux | Linux | affected aa69a8093ff985873cb44fe1157bd6db29a20fe4 cea2a1257a3b5ea3e769a445b34af13e6aa5a123 git | Not specified |
| CNA | Linux | Linux | affected 2.6.29 | Not specified |
| CNA | Linux | Linux | unaffected 2.6.29 semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.75 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.16 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.19.6 6.19.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.0 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/e74c436f8568af1c60942469d0a2300b3ada3857 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/1b72b834511d17f4d069d512f78671f3f210a2f1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/f4fbf2d4750d12ac8525d2efac1016fa0d84d4ec | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/cea2a1257a3b5ea3e769a445b34af13e6aa5a123 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| 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.