CVE-2026-31756
Published: May 2, 2026Last modified: May 2, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: usb: dwc2: gadget: Fix spin_lock/unlock mismatch in dwc2_hsotg_udc_stop() dwc2_gadget_exit_clock_gating() internally calls call_gadget() macro, which expects hsotg->lock to be held since it does spin_unlock/spin_lock around the gadget driver callback invocation. However, dwc2_hsotg_udc_stop() calls dwc2_gadget_exit_clock_gating() without holding the lock. This leads to: - spin_unlock on a lock that is not held (undefined behavior) - The lock remaining held after dwc2_gadget_exit_clock_gating() returns, causing a deadlock when spin_lock_irqsave() is called later in the same function. Fix this by acquiring hsotg->lock before calling dwc2_gadget_exit_clock_gating() and releasing it afterwards, which satisfies the locking requirement of the call_gadget() macro.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 5.5 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity impact | NONE |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Fixed (6.1.168-r0) |
| 25 LTS | linux-lts | Fixed (6.12.81-r0) | |
| Stream | linux-lts | Fixed (6.12.85-r0) |
References
- https://git.kernel.org/stable/c/4ed9d2dd9f29828c311db6ec4b8e0d34bfd6d6a4
- https://git.kernel.org/stable/c/51b62286fc668c6eb74dee7624ec0beec3c5a0ed
- https://git.kernel.org/stable/c/61937f686290494998236c680ce0836b8dd63a3f
- https://git.kernel.org/stable/c/8ffe31acb3b77a30ae34d01719a269881569fb7f
- https://git.kernel.org/stable/c/9bb4b5ed7f8c4f95cc556bdf042b0ba2fa13557a
- https://git.kernel.org/stable/c/beab10429439e20708036a66fb0d97ffb79da6a1
- https://git.kernel.org/stable/c/e9fcca3e87463013d595c65c2189ffaa32ad3b50