CVE-2026-23056

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

uacce: implement mremap in uacce_vm_ops to return -EPERM

The current uacce_vm_ops does not support the mremap operation of

vm_operations_struct. Implement .mremap to return -EPERM to remind

users.

The reason we need to explicitly disable mremap is that when the

driver does not implement .mremap, it uses the default mremap

method. This could lead to a risk scenario:

An application might first mmap address p1, then mremap to p2,

followed by munmap(p1), and finally munmap(p2). Since the default

mremap copies the original vma's vm_private_data (i.e., q) to the

new vma, both munmap operations would trigger vma_close, causing

q->qfr to be freed twice(qfr will be set to null here, so repeated

release is ok).

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References