CVE-2025-68794

An integer underflow flaw was found in the Linux kernel's iomap layer. The iomap_adjust_read_range() function assumes block-aligned positions but can receive non-aligned inputs from certain filesystems like EROFS. This causes incorrect calculations that can underflow the length and return positions beyond the folio, leading to potential out-of-bounds access.

Syzkaller discovered this through EROFS filesystem testing. The issue can cause incorrect read operations and potential crashes. Systems not using EROFS or other filesystems that pass non-aligned positions to iomap are less likely to be affected.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.