Updated: 2025-11-19 04:31:39.823635
Description:
In the Linux kernel, the following vulnerability has been resolved: loop: Fix use-after-free issues do_req_filebacked() calls blk_mq_complete_request() synchronously or asynchronously when using asynchronous I/O unless memory allocation fails. Hence, modify loop_handle_cmd() such that it does not dereference 'cmd' nor 'rq' after do_req_filebacked() finished unless we are sure that the request has not yet been completed. This patch fixes the following kernel crash: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000054 Call trace: css_put.42938+0x1c/0x1ac loop_process_work+0xc8c/0xfd4 loop_rootcg_workfn+0x24/0x34 process_one_work+0x244/0x558 worker_thread+0x400/0x8fc kthread+0x16c/0x1e0 ret_from_fork+0x10/0x20
| Links | NIST | CIRCL | RHEL | Ubuntu |
| Severity | Score | |
|---|---|---|
| CVSS Version 2.x | 0.0 | |
| CVSS Version 3.x | HIGH | 7.8 |
| OS name | Project name | Version | Score | Severity | Status | Errata | Last updated | Statement |
|---|---|---|---|---|---|---|---|---|
| AlmaLinux 9.2 ESU | kernel | 5.14.0 | 7.8 | HIGH | Released | CLSA-2025:1765463110 | 2025-12-11 15:41:02 | |
| CentOS 8.4 ELS | kernel | 4.18.0 | 7.8 | HIGH | Released | CLSA-2026:1771078945 | 2026-02-14 21:09:39 | |
| CentOS 8.5 ELS | kernel | 4.18.0 | 7.8 | HIGH | Released | CLSA-2026:1771077729 | 2026-02-14 21:09:40 | |
| Ubuntu 16.04 ELS | linux-hwe | 4.15.0 | 7.8 | HIGH | Needs Triage | 2025-11-19 08:50:58 | ||
| Ubuntu 16.04 ELS | linux | 4.4.0 | 7.8 | HIGH | Needs Triage | 2025-11-19 09:11:11 | ||
| Ubuntu 18.04 ELS | linux | 4.15.0 | 7.8 | HIGH | Needs Triage | 2025-11-19 09:11:10 |