| From bippy-1.1.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-36908: blk-iocost: do not WARN if iocg was already offlined |
| |
| Description |
| =========== |
| |
| 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. |
| |
| The Linux kernel CVE team has assigned CVE-2024-36908 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.4 with commit 7caa47151ab2e644dd221f741ec7578d9532c9a3 and fixed in 5.10.237 with commit 56a9d07f427378eeb75b917bb49c6fbea8204126 |
| Issue introduced in 5.4 with commit 7caa47151ab2e644dd221f741ec7578d9532c9a3 and fixed in 5.15.181 with commit 7d215e013d097ed6fc4b0ad0272c9514214dc408 |
| Issue introduced in 5.4 with commit 7caa47151ab2e644dd221f741ec7578d9532c9a3 and fixed in 6.1.135 with commit aed0aac18f039dd4af13c143063754efca358cb0 |
| Issue introduced in 5.4 with commit 7caa47151ab2e644dd221f741ec7578d9532c9a3 and fixed in 6.6.31 with commit 1c172ac7afe4442964f4153b2c78fe4e005d9d67 |
| Issue introduced in 5.4 with commit 7caa47151ab2e644dd221f741ec7578d9532c9a3 and fixed in 6.8.10 with commit 14b3275f93d4a0d8ddc02195bc4e9869b7a3700e |
| Issue introduced in 5.4 with commit 7caa47151ab2e644dd221f741ec7578d9532c9a3 and fixed in 6.9 with commit 01bc4fda9ea0a6b52f12326486f07a4910666cf6 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2024-36908 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| block/blk-iocost.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/56a9d07f427378eeb75b917bb49c6fbea8204126 |
| https://git.kernel.org/stable/c/7d215e013d097ed6fc4b0ad0272c9514214dc408 |
| https://git.kernel.org/stable/c/aed0aac18f039dd4af13c143063754efca358cb0 |
| https://git.kernel.org/stable/c/1c172ac7afe4442964f4153b2c78fe4e005d9d67 |
| https://git.kernel.org/stable/c/14b3275f93d4a0d8ddc02195bc4e9869b7a3700e |
| https://git.kernel.org/stable/c/01bc4fda9ea0a6b52f12326486f07a4910666cf6 |
