CVE-2024-27055 Affecting kernel-rt package, versions *

Note: Versions mentioned in the description apply only to the upstream kernel-rt package and not the kernel-rt package as distributed by Centos. See How to fix? for Centos:8 relevant fixed versions and status.

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

workqueue: Don't call cpumask_test_cpu() with -1 CPU in wq_update_node_max_active()

For wq_update_node_max_active(), @off_cpu of -1 indicates that no CPU is going down. The function was incorrectly calling cpumask_test_cpu() with -1 CPU leading to oopses like the following on some archs:

Unable to handle kernel paging request at virtual address ffff0002100296e0 .. pc : wq_update_node_max_active+0x50/0x1fc lr : wq_update_node_max_active+0x1f0/0x1fc ... Call trace: wq_update_node_max_active+0x50/0x1fc apply_wqattrs_commit+0xf0/0x114 apply_workqueue_attrs_locked+0x58/0xa0 alloc_workqueue+0x5ac/0x774 workqueue_init_early+0x460/0x540 start_kernel+0x258/0x684 __primary_switched+0xb8/0xc0 Code: 9100a273 35000d01 53067f00 d0016dc1 (f8607a60) ---[ end trace 0000000000000000 ]--- Kernel panic - not syncing: Attempted to kill the idle task! ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]---

Fix it.

• https://access.redhat.com/security/cve/CVE-2024-27055
• https://git.kernel.org/stable/c/15930da42f8981dc42c19038042947b475b19f47
• https://git.kernel.org/stable/c/38c19c44cc05ec1e84d2e31a9a289b83b6c7ec85
• https://git.kernel.org/stable/c/7df62b8cca38aa452b508b477b16544cba615084
• https://git.kernel.org/stable/c/9fc557d489f8163c1aabcb89114b8eba960f4097
• https://git.kernel.org/stable/c/a75ac2693d734d20724f0e10e039ca85f1fcfc4e
• https://git.kernel.org/stable/c/adc646d2126988a64234502f579e4bc2b080d7cf