Jorgen Hansen

**Name of the Vulnerable Software and Affected Versions** Linux kernel (affected versions not specified) **Description** A vulnerability in the Linux kernel has been resolved, specifically in the zonefs module. The issue occurs when a readahead is issued to a sequential zone file with an offset exactly equal to the current file size. This causes the iomap type to be set to IOMAP UNWRITTEN, which prevents an IO, but the iomap length is calculated as 0, resulting in a WARN ON() in iomap iter(). Furthermore, this causes iomap readahead() to loop forever as iomap readahead iter() always returns 0, making no progress. The fix involves treating reads after the file size as access to holes, setting the iomap type to IOMAP HOLE, and using the length argument as is for the iomap length. **Recommendations** At the moment, there is no information about a newer version that contains a fix for this vulnerability.