CVE-2026-90182

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

blk-iocost: clear delay state when freeing policy data

iocg_kick_delay() turns sufficiently large debt into an explicit

block-cgroup delay with blkcg_set_delay(), setting blkg->use_delay to

-1 and incrementing blkcg->congestion_count. Clearing it again depends

on iocg_kick_delay() running from the period timer, the waitq timer or

the issue path.

ioc_pd_free() removes the iocg from active_iocgs and cancels its waitq

timer, and no further bios can arrive, so once it has run nothing is

left which can reduce the debt and clear the delay. The blkcg stays

marked congested for the rest of its life.

blk_cgroup_congested() then returns true for every task in that cgroup

and its descendants: page_cache_sync_ra() cuts readahead to a single

page, page_cache_async_ra() skips it altogether, and

__folio_throttle_swaprate() takes swap_avail_lock and schedules a

throttle on anonymous folio allocation.

Clear it explicitly, after

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References