x86/entry_32: Clear CPU buffers after register restore in NMI return
In the Linux kernel, the following vulnerability has been resolved: x86/entry_32: Clear CPU buffers after register restore in NMI return CPU buffers are currently cleared after call to exc_nmi, but before register state is restored. This may be okay for MDS mitigation but not for RDFS. Because RDFS mitigation requires CPU buffers to be cleared when registers don't have any sensitive data. Move CLEAR_CPU_BUFFERS after RESTORE_ALL_NMI.
02 / AFFECTED SOFTWARE
Affected packages
909 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: x86/entry_32: Clear CPU buffers after register restore in NMI return CPU buffers are currently cleared after call to exc_nmi, but before register state is restored. This may be okay for MDS mitigation but not for RDFS. Because RDFS mitigation requires CPU buffers to be cleared when registers don't have any sensitive data. Move CLEAR_CPU_BUFFERS after RESTORE_ALL_NMI.
05 / REFERENCES
Further evidence
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/227358e89703c344008119be7e8ffa3fdb5b92de
- https://git.kernel.org/stable/c/43778de19d2ef129636815274644b9c16e78c66b
- https://git.kernel.org/stable/c/48a2440d0f20c826b884e04377ccc1e4696c84e9
- https://git.kernel.org/stable/c/64adf22c4bc73ede920baca5defefb70f190cdbc
- https://git.kernel.org/stable/c/6f44a5fc15b5cece0785bc07453db77d99b0a6de
- https://git.kernel.org/stable/c/b6400eb0b347821efc57760221f8fb6d63b9548a
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/50xxx/CVE-2024-50193.json
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html
- https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html
- https://nvd.nist.gov/vuln/detail/CVE-2024-50193