{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-40319","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-04-16T07:20:57.186Z","datePublished":"2025-12-08T00:46:46.448Z","dateUpdated":"2026-08-05T12:09:31.491Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:09:31.491Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Sync pending IRQ work before freeing ring buffer\n\nFix a race where irq_work can be queued in bpf_ringbuf_commit()\nbut the ring buffer is freed before the work executes.\nIn the syzbot reproducer, a BPF program attached to sched_switch\ntriggers bpf_ringbuf_commit(), queuing an irq_work. If the ring buffer\nis freed before this work executes, the irq_work thread may accesses\nfreed memory.\nCalling `irq_work_sync(&rb->work)` ensures that all pending irq_work\ncomplete before freeing the buffer."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerability is reached through the `bpf()` syscall — creating a ringbuf map, loading a program that calls `bpf_ringbuf_output`/`submit`, and closing the fds to drive `ringbuf_map_free()`. There is no path for a remote peer to load BPF programs, so local system access is required.\nAC:L - The attacker controls both sides of the race: he triggers `bpf_ringbuf_commit()` on demand (loopback packet into his own socket filter, using `BPF_RB_FORCE_WAKEUP` to guarantee `irq_work_queue()` on every commit) and separately triggers the free by detaching and closing the map/prog fds, looping unboundedly. On PREEMPT_RT the work is deferred to the `irq_workd` kthread and on architectures without `arch_irq_work_has_interrupt()` to the next tick, widening the window to milliseconds; syzbot both reproduced the bug and confirmed the fix.\nPR:L - `BPF_MAP_TYPE_RINGBUF`/`USER_RINGBUF` are listed as unprivileged map types in `map_create()`, the ringbuf helpers sit above the `CAP_BPF` gate in `bpf_base_func_proto()`, `BPF_PROG_TYPE_SOCKET_FILTER` is exempt from the CAP_BPF prog-load check, and `SO_ATTACH_BPF` has no capability check — so an ordinary unprivileged user can build the entire chain on the upstream default `unprivileged_bpf_disabled=0`.\nUI:N - The attacker performs every step himself — map creation, program load, socket attach, packet injection, and fd close — with no victim action or cooperating process required.\nS:U - The use-after-free corrupts kernel memory and the per-CPU irq_work list within the same security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - `irq_work_single()` and `bpf_ringbuf_notify()`/`wake_up_all()` read `work->node.llist`, `work->func`, `work->irqwait.task`, and the `waitq` list head out of freed memory, and the vmalloc VA range can be reclaimed with a large vmalloc-backed `BPF_MAP_TYPE_ARRAY` whose contents the attacker sets — turning the dangling traversal into an arbitrary kernel-memory read/disclosure primitive.\nI:H - The irq_work core performs `atomic_set()`/`atomic_cmpxchg()` writes into the freed object and an indirect call `work->func(work)` on a pointer read from it, while `wake_up_all()` adds `list_del_init()` unlink writes and a second function-pointer call — after VA-range reclamation with controlled data this is a direct control-flow hijack and arbitrary-write path to privilege escalation.\nA:H - This is a use-after-free reported by syzbot as a KASAN splat; in the common case the irq_work dereferences an already-unmapped vmalloc address from hardirq or the `irq_workd` kthread, producing an unhandled page fault and kernel panic, and it can be re-triggered in a loop."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/ringbuf.c"],"versions":[{"version":"457f44363a8894135c85b7a9afd2bd8196db24ab","lessThan":"47626748a2a00068dbbd5836d19076637b4e235b","status":"affected","versionType":"git"},{"version":"457f44363a8894135c85b7a9afd2bd8196db24ab","lessThan":"de2ce6b14bc3e565708a39bdba3ef9162aeffc72","status":"affected","versionType":"git"},{"version":"457f44363a8894135c85b7a9afd2bd8196db24ab","lessThan":"e1828c7a8d8135e21ff6adaaa9458c32aae13b11","status":"affected","versionType":"git"},{"version":"457f44363a8894135c85b7a9afd2bd8196db24ab","lessThan":"6451141103547f4efd774e912418a3b4318046c6","status":"affected","versionType":"git"},{"version":"457f44363a8894135c85b7a9afd2bd8196db24ab","lessThan":"10ca3b2eec384628bc9f5d8190aed9427ad2dde6","status":"affected","versionType":"git"},{"version":"457f44363a8894135c85b7a9afd2bd8196db24ab","lessThan":"430e15544f11f8de26b2b5109c7152f71b78295e","status":"affected","versionType":"git"},{"version":"457f44363a8894135c85b7a9afd2bd8196db24ab","lessThan":"4e9077638301816a7d73fa1e1b4c1db4a7e3b59c","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/ringbuf.c"],"versions":[{"version":"5.8","status":"affected"},{"version":"0","lessThan":"5.8","status":"unaffected","versionType":"semver"},{"version":"5.10.247","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.197","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.159","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.117","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.58","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.17.8","lessThanOrEqual":"6.17.*","status":"unaffected","versionType":"semver"},{"version":"6.18","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"5.10.247"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"5.15.197"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.1.159"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.6.117"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.12.58"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.17.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.18"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/47626748a2a00068dbbd5836d19076637b4e235b"},{"url":"https://git.kernel.org/stable/c/de2ce6b14bc3e565708a39bdba3ef9162aeffc72"},{"url":"https://git.kernel.org/stable/c/e1828c7a8d8135e21ff6adaaa9458c32aae13b11"},{"url":"https://git.kernel.org/stable/c/6451141103547f4efd774e912418a3b4318046c6"},{"url":"https://git.kernel.org/stable/c/10ca3b2eec384628bc9f5d8190aed9427ad2dde6"},{"url":"https://git.kernel.org/stable/c/430e15544f11f8de26b2b5109c7152f71b78295e"},{"url":"https://git.kernel.org/stable/c/4e9077638301816a7d73fa1e1b4c1db4a7e3b59c"}],"title":"bpf: Sync pending IRQ work before freeing ring buffer","x_generator":{"engine":"bippy-1.2.0"}}}}