CVE-2024-36908: 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: blk-iocost: do not WARN if iocg was already offlined In iocg_pay_debt(), warn is triggered if 'active_list' is empty, which is intended to confirm iocg is active when it has debt. However, warn can be triggered during a blkcg or disk removal, if iocg_waitq_timer_fn() is run at that time: WARNING: CPU: 0 PID: 2344971 at block/blk-iocost.c:1402 iocg_pay_debt+0x14c/0x190 Call trace: iocg_pay_debt+0x14c/0x190 iocg_kick_waitq+0x438/0x4c0 iocg_waitq_timer_fn+0xd8/0x130 __run_hrtimer+0x144/0x45c __hrtimer_run_queues+0x16c/0x244 hrtimer_interrupt+0x2cc/0x7b0 The warn in this situation is meaningless. Since this iocg is being removed, the state of the 'active_list' is irrelevant, and 'waitq_timer' is canceled after removing 'active_list' in ioc_pd_free(), which ensures iocg is freed after iocg_waitq_timer_fn() returns. Therefore, add the check if iocg was already offlined to avoid warn when removing a blkcg or disk.

Affected products

• Linux Linux Kernel: from 5.4, before 5.10.237 (fixed in 5.10.237); from 5.11, before 5.15.181 (fixed in 5.15.181); from 5.16, before 6.1.135 (fixed in 6.1.135); from 6.2, before 6.6.31 (fixed in 6.6.31); from 6.7, before 6.8.10 (fixed in 6.8.10); version 6.9 only

Published 2024-05-30. Last modified 2026-06-17.