CVE-2025-40126

/// Technical description

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

sparc: fix accurate exception reporting in copy_{from_to}_user for UltraSPARC

The referenced commit introduced exception handlers on user-space memory

references in copy_from_user and copy_to_user. These handlers return from

the respective function and calculate the remaining bytes left to copy

using the current register contents. This commit fixes a couple of bad

calculations. This will fix the return value of copy_from_user and

copy_to_user in the faulting case. The behaviour of memcpy stays unchanged.

/// 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