{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-68751", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-12-24T10:30:51.032Z", "datePublished": "2026-01-05T09:32:25.534Z", "dateUpdated": "2026-05-11T21:52:38.615Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T21:52:38.615Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ns390/fpu: Fix false-positive kmsan report in fpu_vstl()\n\nA false-positive kmsan report is detected when running ping command.\n\nAn inline assembly instruction 'vstl' can write varied amount of bytes\ndepending on value of 'index' argument. If 'index' > 0, 'vstl' writes\nat least 2 bytes.\n\nclang generates kmsan write helper call depending on inline assembly\nconstraints. Constraints are evaluated compile-time, but value of\n'index' argument is known only at runtime.\n\nclang currently generates call to __msan_instrument_asm_store with 1 byte\nas size. Manually call kmsan function to indicate correct amount of bytes\nwritten and fix false-positive report.\n\nThis change fixes following kmsan reports:\n\n[ 36.563119] =====================================================\n[ 36.563594] BUG: KMSAN: uninit-value in virtqueue_add+0x35c6/0x7c70\n[ 36.563852] virtqueue_add+0x35c6/0x7c70\n[ 36.564016] virtqueue_add_outbuf+0xa0/0xb0\n[ 36.564266] start_xmit+0x288c/0x4a20\n[ 36.564460] dev_hard_start_xmit+0x302/0x900\n[ 36.564649] sch_direct_xmit+0x340/0xea0\n[ 36.564894] __dev_queue_xmit+0x2e94/0x59b0\n[ 36.565058] neigh_resolve_output+0x936/0xb40\n[ 36.565278] __neigh_update+0x2f66/0x3a60\n[ 36.565499] neigh_update+0x52/0x60\n[ 36.565683] arp_process+0x1588/0x2de0\n[ 36.565916] NF_HOOK+0x1da/0x240\n[ 36.566087] arp_rcv+0x3e4/0x6e0\n[ 36.566306] __netif_receive_skb_list_core+0x1374/0x15a0\n[ 36.566527] netif_receive_skb_list_internal+0x1116/0x17d0\n[ 36.566710] napi_complete_done+0x376/0x740\n[ 36.566918] virtnet_poll+0x1bae/0x2910\n[ 36.567130] __napi_poll+0xf4/0x830\n[ 36.567294] net_rx_action+0x97c/0x1ed0\n[ 36.567556] handle_softirqs+0x306/0xe10\n[ 36.567731] irq_exit_rcu+0x14c/0x2e0\n[ 36.567910] do_io_irq+0xd4/0x120\n[ 36.568139] io_int_handler+0xc2/0xe8\n[ 36.568299] arch_cpu_idle+0xb0/0xc0\n[ 36.568540] arch_cpu_idle+0x76/0xc0\n[ 36.568726] default_idle_call+0x40/0x70\n[ 36.568953] do_idle+0x1d6/0x390\n[ 36.569486] cpu_startup_entry+0x9a/0xb0\n[ 36.569745] rest_init+0x1ea/0x290\n[ 36.570029] start_kernel+0x95e/0xb90\n[ 36.570348] startup_continue+0x2e/0x40\n[ 36.570703]\n[ 36.570798] Uninit was created at:\n[ 36.571002] kmem_cache_alloc_node_noprof+0x9e8/0x10e0\n[ 36.571261] kmalloc_reserve+0x12a/0x470\n[ 36.571553] __alloc_skb+0x310/0x860\n[ 36.571844] __ip_append_data+0x483e/0x6a30\n[ 36.572170] ip_append_data+0x11c/0x1e0\n[ 36.572477] raw_sendmsg+0x1c8c/0x2180\n[ 36.572818] inet_sendmsg+0xe6/0x190\n[ 36.573142] __sys_sendto+0x55e/0x8e0\n[ 36.573392] __s390x_sys_socketcall+0x19ae/0x2ba0\n[ 36.573571] __do_syscall+0x12e/0x240\n[ 36.573823] system_call+0x6e/0x90\n[ 36.573976]\n[ 36.574017] Byte 35 of 98 is uninitialized\n[ 36.574082] Memory access of size 98 starts at 0000000007aa0012\n[ 36.574218]\n[ 36.574325] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G B N 6.17.0-dirty #16 NONE\n[ 36.574541] Tainted: [B]=BAD_PAGE, [N]=TEST\n[ 36.574617] Hardware name: IBM 3931 A01 703 (KVM/Linux)\n[ 36.574755] =====================================================\n\n[ 63.532541] =====================================================\n[ 63.533639] BUG: KMSAN: uninit-value in virtqueue_add+0x35c6/0x7c70\n[ 63.533989] virtqueue_add+0x35c6/0x7c70\n[ 63.534940] virtqueue_add_outbuf+0xa0/0xb0\n[ 63.535861] start_xmit+0x288c/0x4a20\n[ 63.536708] dev_hard_start_xmit+0x302/0x900\n[ 63.537020] sch_direct_xmit+0x340/0xea0\n[ 63.537997] __dev_queue_xmit+0x2e94/0x59b0\n[ 63.538819] neigh_resolve_output+0x936/0xb40\n[ 63.539793] ip_finish_output2+0x1ee2/0x2200\n[ 63.540784] __ip_finish_output+0x272/0x7a0\n[ 63.541765] ip_finish_output+0x4e/0x5e0\n[ 63.542791] ip_output+0x166/0x410\n[ 63.543771] ip_push_pending_frames+0x1a2/0x470\n[ 63.544753] raw_sendmsg+0x1f06/0x2180\n[ 63.545033] inet_sendmsg+0xe6/0x190\n[ 63.546006] __sys_sendto+0x55e/0x8e0\n---truncated---" } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "arch/s390/include/asm/fpu-insn.h" ], "versions": [ { "version": "dcd3e1de9d17dc43dfed87a9fc814b9dec508043", "lessThan": "946357a538bb47740635c25520924351d2d91544", "status": "affected", "versionType": "git" }, { "version": "dcd3e1de9d17dc43dfed87a9fc814b9dec508043", "lessThan": "13dcd6308cb8f67134ee5d5d762b2a66363c695b", "status": "affected", "versionType": "git" }, { "version": "dcd3e1de9d17dc43dfed87a9fc814b9dec508043", "lessThan": "14e4e4175b64dd9216b522f6ece8af6997d063b2", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "arch/s390/include/asm/fpu-insn.h" ], "versions": [ { "version": "6.9", "status": "affected" }, { "version": "0", "lessThan": "6.9", "status": "unaffected", "versionType": "semver" }, { "version": "6.17.13", "lessThanOrEqual": "6.17.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.2", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19", "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": "6.9", "versionEndExcluding": "6.17.13" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.18.2" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.19" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/946357a538bb47740635c25520924351d2d91544" }, { "url": "https://git.kernel.org/stable/c/13dcd6308cb8f67134ee5d5d762b2a66363c695b" }, { "url": "https://git.kernel.org/stable/c/14e4e4175b64dd9216b522f6ece8af6997d063b2" } ], "title": "s390/fpu: Fix false-positive kmsan report in fpu_vstl()", "x_generator": { "engine": "bippy-1.2.0" } } } }