CVE-2024-50249: ACPI: CPPC: Make rmw_lock a raw_spin_lock

First published: Sat Nov 09 2024(Updated: )

In the Linux kernel, the following vulnerability has been resolved: ACPI: CPPC: Make rmw_lock a raw_spin_lock The following BUG was triggered: ============================= [ BUG: Invalid wait context ] 6.12.0-rc2-XXX #406 Not tainted ----------------------------- kworker/1:1/62 is trying to lock: ffffff8801593030 (&cpc_ptr->rmw_lock){+.+.}-{3:3}, at: cpc_write+0xcc/0x370 other info that might help us debug this: context-{5:5} 2 locks held by kworker/1:1/62: #0: ffffff897ef5ec98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2c/0x50 #1: ffffff880154e238 (&sg_policy->update_lock){....}-{2:2}, at: sugov_update_shared+0x3c/0x280 stack backtrace: CPU: 1 UID: 0 PID: 62 Comm: kworker/1:1 Not tainted 6.12.0-rc2-g9654bd3e8806 #406 Workqueue: 0x0 (events) Call trace: dump_backtrace+0xa4/0x130 show_stack+0x20/0x38 dump_stack_lvl+0x90/0xd0 dump_stack+0x18/0x28 __lock_acquire+0x480/0x1ad8 lock_acquire+0x114/0x310 _raw_spin_lock+0x50/0x70 cpc_write+0xcc/0x370 cppc_set_perf+0xa0/0x3a8 cppc_cpufreq_fast_switch+0x40/0xc0 cpufreq_driver_fast_switch+0x4c/0x218 sugov_update_shared+0x234/0x280 update_load_avg+0x6ec/0x7b8 dequeue_entities+0x108/0x830 dequeue_task_fair+0x58/0x408 __schedule+0x4f0/0x1070 schedule+0x54/0x130 worker_thread+0xc0/0x2e8 kthread+0x130/0x148 ret_from_fork+0x10/0x20 sugov_update_shared() locks a raw_spinlock while cpc_write() locks a spinlock. To have a correct wait-type order, update rmw_lock to a raw spinlock and ensure that interrupts will be disabled on the CPU holding it. [ rjw: Changelog edits ]

Credit: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Never miss a vulnerability like this again

Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.

Read MoreStart Free Trial

• agent/title
• agent/references
• agent/type
• agent/description
• agent/first-publish-date
• agent/author
• agent/event
• agent/remedy
• agent/severity
• collector/mitre-cve
• source/MITRE
• agent/last-modified-date
• agent/source
• collector/nvd-api
• source/NVD
• agent/software-canonical-lookup
• agent/software-canonical-lookup-request
• agent/softwarecombine
• agent/tags
• collector/usn-cve
• source/Ubuntu
• collector/launchpad-cve
• source/Launchpad
• collector/security-tracker-debian
• source/Debian
• vendor/linux
• canonical/linux kernel
• version/linux kernel/5.15.168
• version/linux kernel/6.1.113
• version/linux kernel/6.6.54
• version/linux kernel/6.10.13
• version/linux kernel/6.11.2
• version/linux kernel/6.12-rc1
• version/linux kernel/6.12-rc2
• version/linux kernel/6.12-rc3
• version/linux kernel/6.12-rc4
• version/linux kernel/6.12-rc5
• package-manager/debian