CVE-2026-63907: uio: uio_pci_generic_sva: fix double free of devm_kzalloc() memory

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-19 · updated 2026-10-30
Weakness: CWE-415

Description

In the Linux kernel, the following vulnerability has been resolved: uio: uio_pci_generic_sva: fix double free of devm_kzalloc() memory uio_pci_sva allocates struct uio_pci_sva_dev with devm_kzalloc() in probe(), but then calls kfree(udev) both on the probe() error path (label out_free) and again in remove(). Because devm_kzalloc() allocations are devres-managed and are freed automatically when the device is detached (including after a failing probe() and during driver unbind), the explicit kfree() can lead to a double free. If probe() fails after devm_kzalloc(), the error path frees udev and devres cleanup will free it again when the core unwinds the partially bound device. On normal driver removal, remove() frees udev and devres will free it again when the device is detached. This issue was identified by a static analysis tool I developed and confirmed by manual review. Fix by removing the manual kfree() calls and dropping the now-unused label.

Affected products

Linux kernel: from 6.19 before 7.0.12; 7.1-rc1, 7.1-rc2, 7.1-rc3, 7.1-rc4, 7.1-rc5 — fixed in 7.0.12
Linux kernel: 6.19 — fixed in 7.1

How to fix

Upgrade to a fixed version: Linux kernel 7.0.12; Linux kernel 7.1. Check the vendor advisory for mitigations.

References

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