CVE-2024-35929
What it is
In the Linux kernel, the following vulnerability has been resolved: rcu/nocb: Fix WARN_ON_ONCE() in the rcu_nocb_bypass_lock() For the kernels built with CONFIG_RCU_NOCB_CPU_DEFAULT_ALL=y and CONFIG_RCU_LAZY=y, the following scenarios will trigger WARN_ON_ONCE() in the rcu_nocb_bypass_lock() and rcu_nocb_wait_contended() functions: CPU2 CPU11 kthread rcu_nocb_cb_kthread ksys_write rcu_do_batch vfs_write rcu_torture_timer_cb proc_sys_write __kmem_cache_free proc_sys_call_handler kmemleak_free drop_caches_sysctl_handler delete_object_full drop_slab __delete_object shrink_slab put_object lazy_rcu_shrink_scan call_rcu rcu_nocb_flush_bypass __call_rcu_commn rcu_nocb_bypass_lock raw_spin_trylock(&rdp->nocb_bypass_lock) fail atomic_inc(&rdp->nocb_lock_contended); rcu_nocb_wait_contended WARN_ON_ONCE(smp_processor_id() != rdp->cpu); WARN_ON_ONCE(atomic_read(&rdp->nocb_lock_contended)) | |_ _ _ _ _ _ _ _ _ _same rdp and rdp->cpu != 11_ _ _ _ _ _ _ _ _ __| Reproduce this bug with "echo 3 > /proc/sys/vm/drop_caches". This commit therefore uses rcu_nocb_try_flush_bypass() instead of rcu_nocb_flush_bypass() in lazy_rcu_shrink_scan(). If the nocb_bypass queue is being flushed, then rcu_nocb_try_flush_bypass will return directly.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Record status
- Analyzed
Affected
- Linux Kernel < 6.6.27
- Linux Kernel < 6.8.6
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2024-35929.md and follow it. Check whether this project is affected by CVE-2024-35929. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/4d58c9fb45c70e62c19e8be3f3605889c47601bc
- https://git.kernel.org/stable/c/927d1f4f77e4784ab3944a9df86ab14d1cd3185a
- https://git.kernel.org/stable/c/dda98810b552fc6bf650f4270edeebdc2f28bd3f
- https://git.kernel.org/stable/c/4d58c9fb45c70e62c19e8be3f3605889c47601bc
- https://git.kernel.org/stable/c/927d1f4f77e4784ab3944a9df86ab14d1cd3185a
- https://git.kernel.org/stable/c/dda98810b552fc6bf650f4270edeebdc2f28bd3f
References
- https://git.kernel.org/stable/c/4d58c9fb45c70e62c19e8be3f3605889c47601bc
- https://git.kernel.org/stable/c/927d1f4f77e4784ab3944a9df86ab14d1cd3185a
- https://git.kernel.org/stable/c/dda98810b552fc6bf650f4270edeebdc2f28bd3f
- https://git.kernel.org/stable/c/4d58c9fb45c70e62c19e8be3f3605889c47601bc
- https://git.kernel.org/stable/c/927d1f4f77e4784ab3944a9df86ab14d1cd3185a
- https://git.kernel.org/stable/c/dda98810b552fc6bf650f4270edeebdc2f28bd3f