{ "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 \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 \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" } } } }