cvedb.io
CVE-2025-38709
MEDIUM · CVSS 5.5
EPSS exploitation probability: 0%
Published 2025-09-04T16:15:39.997 · Last modified 2026-06-17T09:17:42.557

Summary

In the Linux kernel, the following vulnerability has been resolved: loop: Avoid updating block size under exclusive owner Syzbot came up with a reproducer where a loop device block size is changed underneath a mounted filesystem. This causes a mismatch between the block device block size and the block size stored in the superblock causing confusion in various places such as fs/buffer.c. The particular issue triggered by syzbot was a warning in __getblk_slow() due to requested buffer size not matching block device block size. Fix the problem by getting exclusive hold of the loop device to change its block size. This fails if somebody (such as filesystem) has already an exclusive ownership of the block device and thus prevents modifying the loop device under some exclusive owner which doe

Affected products

linux — linux_kernel

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.