CVE-2025-21832: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: block: don't revert iter for -EIOCBQUEUED blkdev_read_iter() has a few odd checks, like gating the position and count adjustment on whether or not the result is bigger-than-or-equal to zero (where bigger than makes more sense), and not checking the return value of blkdev_direct_IO() before doing an iov_iter_revert(). The latter can lead to attempting to revert with a negative value, which when passed to iov_iter_revert() as an unsigned value will lead to throwing a WARN_ON() because unroll is bigger than MAX_RW_COUNT. Be sane and don't revert for -EIOCBQUEUED, like what is done in other spots.

Affected products

• Linux Linux Kernel: from 5.17.1, before 6.1.129 (fixed in 6.1.129); from 6.2, before 6.6.78 (fixed in 6.6.78); from 6.7, before 6.12.14 (fixed in 6.12.14); from 6.13, before 6.13.3 (fixed in 6.13.3); version 5.17 only

Published 2025-03-06. Last modified 2026-07-30.