{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2023-53577","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-10-04T15:14:15.926Z","datePublished":"2025-10-04T15:17:16.632Z","dateUpdated":"2026-08-05T09:14:55.401Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T09:14:55.401Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf, cpumap: Make sure kthread is running before map update returns\n\nThe following warning was reported when running stress-mode enabled\nxdp_redirect_cpu with some RT threads:\n\n  ------------[ cut here ]------------\n  WARNING: CPU: 4 PID: 65 at kernel/bpf/cpumap.c:135\n  CPU: 4 PID: 65 Comm: kworker/4:1 Not tainted 6.5.0-rc2+ #1\n  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)\n  Workqueue: events cpu_map_kthread_stop\n  RIP: 0010:put_cpu_map_entry+0xda/0x220\n  ......\n  Call Trace:\n   <TASK>\n   ? show_regs+0x65/0x70\n   ? __warn+0xa5/0x240\n   ......\n   ? put_cpu_map_entry+0xda/0x220\n   cpu_map_kthread_stop+0x41/0x60\n   process_one_work+0x6b0/0xb80\n   worker_thread+0x96/0x720\n   kthread+0x1a5/0x1f0\n   ret_from_fork+0x3a/0x70\n   ret_from_fork_asm+0x1b/0x30\n   </TASK>\n\nThe root cause is the same as commit 436901649731 (\"bpf: cpumap: Fix memory\nleak in cpu_map_update_elem\"). The kthread is stopped prematurely by\nkthread_stop() in cpu_map_kthread_stop(), and kthread() doesn't call\ncpu_map_kthread_run() at all but XDP program has already queued some\nframes or skbs into ptr_ring. So when __cpu_map_ring_cleanup() checks\nthe ptr_ring, it will find it was not emptied and report a warning.\n\nAn alternative fix is to use __cpu_map_ring_cleanup() to drop these\npending frames or skbs when kthread_stop() returns -EINTR, but it may\nconfuse the user, because these frames or skbs have been handled\ncorrectly by XDP program. So instead of dropping these frames or skbs,\njust make sure the per-cpu kthread is running before\n__cpu_map_entry_alloc() returns.\n\nAfter apply the fix, the error handle for kthread_stop() will be\nunnecessary because it will always return 0, so just remove it."}],"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 - Triggering requires local `bpf()` syscall access to create a `BPF_MAP_TYPE_CPUMAP` and repeatedly update/delete its entries, plus attaching an XDP program — all local operations. Per kernel scoring guidance BPF map manipulation is Local.\nAC:L - The attacker drives both sides of the race: it produces the queued frames/skbs (self-generated traffic through a generic-mode XDP redirect on a veth/lo it controls) and issues the map update that calls `kthread_stop()`, and it chooses the CPU the kthread is bound to so it can starve it with spinner threads or a softirq flood. No special kernel config is required, and the update/delete loop can be repeated indefinitely until the race is won.\nPR:L - Creating the cpumap needs `bpf_capable()` and the XDP program needs `CAP_NET_ADMIN`, but these are delegatable non-root capabilities routinely granted to unprivileged XDP dataplane daemons/containers, not administrative control over the kernel. Consistent with kernel CNA scoring of comparable CAP_BPF/CAP_NET_ADMIN XDP and devmap/cpumap issues (e.g. CVE-2026-23294, CVE-2025-21808).\nUI:N - The entire sequence — map create, XDP attach, traffic generation, and the update/delete that races the kthread — is performed by the attacker's own process. No victim action is involved.\nS:U - The corruption and crash occur inside the kernel itself, within the same security authority as the vulnerable component. There is no VM, IOMMU, or sandbox boundary crossed.\nC:H - In generic/skb XDP mode the leftover ring entries are tagged `sk_buff` pointers passed to `xdp_return_frame()` as `struct xdp_frame *`; when the misread `flags` field sets `XDP_FLAGS_HAS_FRAGS`, `xdp_get_shared_info_from_frame()` builds a wild pointer from misread `data`/`frame_sz` and reads `sinfo->nr_frags` and the frag array out of bounds. This type confusion yields an uncontrolled kernel-memory read primitive whose results feed `page_address()`/`__xdp_return()`.\nI:H - The same type confusion drives `__xdp_return()` with a garbage `mem.type` and garbage `data`, reaching `page_frag_free()`, `put_page()`, or `page_pool_put_full_page()` on uncontrolled pointers — arbitrary page refcount decrements that can prematurely free live pages and be leveraged into a write primitive. Type confusion / memory corruption of this class is scored High.\nA:H - The bug reliably produces a `WARN_ON_ONCE` splat in `__cpu_map_ring_cleanup()` (kernel panic under `panic_on_warn`), and the follow-on wild-pointer dereference in `xdp_return_frame()`/`__xdp_return()` causes a GPF/oops. It also leaks the pending skbs on every occurrence."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/cpumap.c"],"versions":[{"version":"6710e1126934d8b4372b4d2f9ae1646cd3f151bf","lessThan":"b44d28b98f185d2f2348aa3c3636838c316f889e","status":"affected","versionType":"git"},{"version":"6710e1126934d8b4372b4d2f9ae1646cd3f151bf","lessThan":"7a1178a3671b40746830d355836b72e47ceb2490","status":"affected","versionType":"git"},{"version":"6710e1126934d8b4372b4d2f9ae1646cd3f151bf","lessThan":"ecb45b852af5e88257020b88bea5ff0798d72aca","status":"affected","versionType":"git"},{"version":"6710e1126934d8b4372b4d2f9ae1646cd3f151bf","lessThan":"640a604585aa30f93e39b17d4d6ba69fcb1e66c9","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/cpumap.c"],"versions":[{"version":"4.15","status":"affected"},{"version":"0","lessThan":"4.15","status":"unaffected","versionType":"semver"},{"version":"5.15.126","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.45","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.4.10","lessThanOrEqual":"6.4.*","status":"unaffected","versionType":"semver"},{"version":"6.5","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":"4.15","versionEndExcluding":"5.15.126"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.1.45"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.4.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.5"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/b44d28b98f185d2f2348aa3c3636838c316f889e"},{"url":"https://git.kernel.org/stable/c/7a1178a3671b40746830d355836b72e47ceb2490"},{"url":"https://git.kernel.org/stable/c/ecb45b852af5e88257020b88bea5ff0798d72aca"},{"url":"https://git.kernel.org/stable/c/640a604585aa30f93e39b17d4d6ba69fcb1e66c9"}],"title":"bpf, cpumap: Make sure kthread is running before map update returns","x_generator":{"engine":"bippy-1.2.0"}}}}