iommufd: Don't overflow during division for dirty tracking
In the Linux kernel, the following vulnerability has been resolved: iommufd: Don't overflow during division for dirty tracking If pgshift is 63 then BITS_PER_TYPE(*bitmap->bitmap) * pgsize will overflow to 0 and this triggers divide by 0. In this case the index should just be 0, so reorganize things to divide by shift and avoid hitting any overflows.
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: iommufd: Don't overflow during division for dirty tracking If pgshift is 63 then BITS_PER_TYPE(*bitmap->bitmap) * pgsize will overflow to 0 and this triggers divide by 0. In this case the index should just be 0, so reorganize things to divide by shift and avoid hitting any overflows.
05 / REFERENCES
Further evidence
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/07105e61882ff4a7d58db63cc5f9e90c6c60506c
- https://git.kernel.org/stable/c/4c8a4f1d34eced168cc0b3a3dfe7b6dcc2090f69
- https://git.kernel.org/stable/c/cb30dfa75d55eced379a42fd67bd5fb7ec38555e
- https://git.kernel.org/stable/c/dbf316fc90aa954dcd5440817f4b944627ed63e0
- https://git.kernel.org/stable/c/de7f2c67ceb1941b05b04ac35458a03e93cc57b1
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/40xxx/CVE-2025-40293.json
- https://nvd.nist.gov/vuln/detail/CVE-2025-40293