Integer overflow in Linux kernel - CVE-2026-64357

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to an integer overflow in xfs_exchmaps_estimate_overhead() when calculating block reservation overhead for exchange mappings. A local user can trigger the vulnerable calculation to cause a denial of service.

The issue occurs because the limit check is applied to the pre-overhead reservation value instead of the computed reservation value that is later passed to xfs_trans_alloc().

Affected software

How to mitigate CVE-2026-64357

External References

• https://git.kernel.org/stable/c/0a5213bbff62b51c7d4999ac8c7e11ea57d00d45
• https://git.kernel.org/stable/c/4707344b0d36d1012c8a1716e20167cd3afdd5f1
• https://git.kernel.org/stable/c/a62ef2d13d6e7270dd5e88c6082bf2d0edcd5112
• https://git.kernel.org/stable/c/c597c8580d50127fc1221b5a5b653a94d49e23e3

Related Security Bulletins

• Integer overflow in Linux kernel xfs libxfs