# CVE-2023-53067: LoongArch: Only call get_timer_irq() once in constant_clockevent_init() > A kernel bug in LoongArch timer initialization causes a crash when debug options are enabled, leading to denial of service. - **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Any signed-in user - **Attackable:** Local or same network only - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 2 May 2025 - **Updated:** 11 May 2026 - **Also known as:** BELL-CVE-2023-53067, DEBIAN-CVE-2023-53067, GHSA-gwc3-527p-v4v9, ROOT-OS-UBUNTU-2204-CVE-2023-53067, UBUNTU-CVE-2023-53067 ## What is CVE-2023-53067? CVE-2023-53067 is a medium-severity denial of service vulnerability in Linux kernel, published on 2 May 2025. It can only be exploited from the same machine or local network, with no action from the victim. ### Official description In the Linux kernel, the following vulnerability has been resolved: LoongArch: Only call get_timer_irq() once in constant_clockevent_init() Under CONFIG_DEBUG_ATOMIC_SLEEP=y and CONFIG_DEBUG_PREEMPT=y, we can see the following messages on LoongArch, this is because using might_sleep() in preemption disable context. [ 0.001127] smp: Bringing up secondary CPUs ... [ 0.001222] Booting CPU#1... [ 0.001244] 64-bit Loongson Processor probed (LA464 Core) [ 0.001247] CPU1 revision is: 0014c012 (Loongson-64bit) [ 0.001250] FPU1 revision is: 00000000 [ 0.001252] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:283 [ 0.001255] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1 [ 0.001257] preempt_count: 1, expected: 0 [ 0.001258] RCU nest depth: 0, expected: 0 [ 0.001259] Preemption disabled at: [ 0.001261] [<9000000000223800>] arch_dup_task_struct+0x20/0x110 [ 0.001272] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.2.0-rc7+ #43 [ 0.001275] Hardware name: Loongson Loongson-3A5000-7A1000-1w-A2101/Loongson-LS3A5000-7A1000-1w-A2101, BIOS vUDK2018-LoongArch-V4.0.05132-beta10 12/13/202 [ 0.001277] Stack : 0072617764726148 0000000000000000 9000000000222f1c 90000001001e0000 [ 0.001286] 90000001001e3be0 90000001001e3be8 0000000000000000 0000000000000000 [ 0.001292] 90000001001e3be8 0000000000000040 90000001001e3cb8 90000001001e3a50 [ 0.001297] 9000000001642000 90000001001e3be8 be694d10ce4139dd 9000000100174500 [ 0.001303] 0000000000000001 0000000000000001 00000000ffffe0a2 0000000000000020 [ 0.001309] 000000000000002f 9000000001354116 00000000056b0000 ffffffffffffffff [ 0.001314] 0000000000000000 0000000000000000 90000000014f6e90 9000000001642000 [ 0.001320] 900000000022b69c 0000000000000001 0000000000000000 9000000001736a90 [ 0.001325] 9000000100038000 0000000000000000 9000000000222f34 0000000000000000 [ 0.001331] 00000000000000b0 0000000000000004 0000000000000000 0000000000070000 [ 0.001337] ... [ 0.001339] Call Trace: [ 0.001342] [<9000000000222f34>] show_stack+0x5c/0x180 [ 0.001346] [<90000000010bdd80>] dump_stack_lvl+0x60/0x88 [ 0.001352] [<9000000000266418>] __might_resched+0x180/0x1cc [ 0.001356] [<90000000010c742c>] mutex_lock+0x20/0x64 [ 0.001359] [<90000000002a8ccc>] irq_find_matching_fwspec+0x48/0x124 [ 0.001364] [<90000000002259c4>] constant_clockevent_init+0x68/0x204 [ 0.001368] [<900000000022acf4>] start_secondary+0x40/0xa8 [ 0.001371] [<90000000010c0124>] smpboot_entry+0x60/0x64 Here are the complete call chains: smpboot_entry() start_secondary() constant_clockevent_init() get_timer_irq() irq_find_matching_fwnode() irq_find_matching_fwspec() mutex_lock() might_sleep() __might_sleep() __might_resched() In order to avoid the above issue, we should break the call chains, using timer_irq_installed variable as check condition to only call get_timer_irq() once in constant_clockevent_init() is a simple and proper way. ## Which versions are affected by CVE-2023-53067? It affects 1 product. Products: Linux kernel. ## How do I fix CVE-2023-53067? Apply the vendor's patch. ## Is CVE-2023-53067 being exploited? There is no known exploitation of CVE-2023-53067 in the wild and no public exploit code. ## Other vulnerabilities in Linux kernel - [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild) - [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild) - [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild) - [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild) - [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2023-53067 and fix it if it is affected. What it is: CVE-2023-53067 is a medium-severity denial of service vulnerability in Linux kernel, published on 2 May 2025. It can only be exploited from the same machine or local network, with no action from the victim. Exploitation: There is no known exploitation of CVE-2023-53067 in the wild and no public exploit code. Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page. Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2023-53067/ (Markdown: https://insights.sbomify.com/CVE-2023-53067/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2023-53067 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53067 - OSV: https://osv.dev/vulnerability/CVE-2023-53067 --- From sbomify Insights: https://insights.sbomify.com/CVE-2023-53067/ Summaries are generated and may contain mistakes; the official description above is the record.