Bug 2540399 (CVE-2026-97482)
| Summary: | CVE-2026-97482 kernel: usb: gadget: goku_udc: avoid NULL deref of dev->driver in INT_USBRESET log | ||
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| Product: | [Other] Security Response | Reporter: | OSIDB Bzimport <bzimport> |
| Component: | vulnerability | Assignee: | Product Security DevOps Team <prodsec-dev> |
| Status: | NEW --- | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | unspecified | CC: | akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers |
| Target Milestone: | --- | Keywords: | Security |
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | --- | |
| Doc Text: |
A flaw was found in the Linux kernel's goku_udc USB gadget driver. An attacker or event triggering a USB reset interrupt before a gadget driver is bound, or after one is unbound, causes the interrupt handler to access an uninitialized driver pointer while logging the event. This flaw results in a null-pointer dereference, leading to a kernel crash and a Denial of Service (DoS).
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Story Points: | --- |
| Clone Of: | Environment: | ||
| Last Closed: | Type: | --- | |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: goku_udc: avoid NULL deref of dev->driver in INT_USBRESET log goku_irq() handles a number of bus events under a single ep0 path. It already guards the gadget driver suspend/resume callbacks against a NULL ->driver: if (dev->gadget.speed != USB_SPEED_UNKNOWN && dev->driver && dev->driver->resume) { spin_unlock(&dev->lock); dev->driver->resume(&dev->gadget); ... } but the very next branch unconditionally dereferences dev->driver when an INT_USBRESET arrives: if (stat & INT_USBRESET) { ACK(INT_USBRESET); INFO(dev, "USB reset done, gadget %s\n", dev->driver->driver.name); } If the controller raises INT_USBRESET before any gadget driver has been bound (or after one has been unbound), dev->driver is NULL and the printk dereferences NULL. smatch flags the inconsistency: drivers/usb/gadget/udc/goku_udc.c:1618 goku_irq() error: we previously assumed 'dev->driver' could be null (see line 1607) Fall back to a placeholder when the gadget driver is not bound. No functional change while a gadget driver is bound.