iommufd: Prevent ALIGN() overflow
In the Linux kernel, the following vulnerability has been resolved: iommufd: Prevent ALIGN() overflow When allocating IOVA the candidate range gets aligned to the target alignment. If the range is close to ULONG_MAX then the ALIGN() can wrap resulting in a corrupted iova. Open code the ALIGN() using get_add_overflow() to prevent this. This simplifies the checks as we don't need to check for length earlier either. Consolidate the two copies of this code under a single helper. This bug would allow userspace to create a mapping that overlaps with some other mapping or a reserved range.
02 / AFFECTED SOFTWARE
Affected packages
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: iommufd: Prevent ALIGN() overflow When allocating IOVA the candidate range gets aligned to the target alignment. If the range is close to ULONG_MAX then the ALIGN() can wrap resulting in a corrupted iova. Open code the ALIGN() using get_add_overflow() to prevent this. This simplifies the checks as we don't need to check for length earlier either. Consolidate the two copies of this code under a single helper. This bug would allow userspace to create a mapping that overlaps with some other mapping or a reserved range.
05 / REFERENCES
Further evidence
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/79fad1917802c28de51a479318a056a6fbe3e2f2
- https://git.kernel.org/stable/c/b42497e3c0e74db061eafad41c0cd7243c46436b
- https://git.kernel.org/stable/c/d19b817540c0abe84854a64ee9ee34cecc3bbeef
- https://git.kernel.org/stable/c/e42a046bb41dcdde4f766a17d8211842007ed537
- https://git.kernel.org/stable/c/ebb6021560b94649bec6b8faba6fe0dca2218e81
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/38xxx/CVE-2025-38688.json
- https://nvd.nist.gov/vuln/detail/CVE-2025-38688