发布于3月6日3月6日 Members Oracle Linux: CVE-2024-35895: ELSA-2024-6997:kernel security update (IMPORTANT) (Multiple Advisories) Severity 5 CVSS (AV:L/AC:L/Au:S/C:N/I:N/A:C) Published 05/19/2024 Created 10/18/2024 Added 10/16/2024 Modified 01/07/2025 Description In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: Prevent lock inversion deadlock in map delete elem syzkaller started using corpuses where a BPF tracing program deletes elements from a sockmap/sockhash map. Because BPF tracing programs can be invoked from any interrupt context, locks taken during a map_delete_elem operation must be hardirq-safe. Otherwise a deadlock due to lock inversion is possible, as reported by lockdep: CPU0CPU1 -------- lock(&htab->buckets[i].lock); local_irq_disable(); lock(&host->lock); lock(&htab->buckets[i].lock); <Interrupt> lock(&host->lock); Locks in sockmap are hardirq-unsafe by design. We expects elements to be deleted from sockmap/sockhash only in task (normal) context with interrupts enabled, or in softirq context. Detect when map_delete_elem operation is invoked from a context which is _not_ hardirq-unsafe, that is interrupts are disabled, and bail out with an error. Note that map updates are not affected by this issue. BPF verifier does not allow updating sockmap/sockhash from a BPF tracing program today. Solution(s) oracle-linux-upgrade-kernel References https://attackerkb.com/topics/cve-2024-35895 CVE - 2024-35895 ELSA-2024-6997
