{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-80986",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-08-26T14:34:25.811Z",
        "datePublished": "2026-09-11T19:42:44.904Z",
        "dateUpdated": "2026-10-19T08:46:10.570Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-10-19T08:46:10.570Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: bound the peer rkey counts in SMC-Rv2 LLC messages\n\nOn a link whose device has max_recv_sge == 1 there is no shared v2 receive\nbuffer, and smc_llc_save_add_link_rkeys() takes the v2 extension from 44\nbytes past the start of the queue entry's inline message:\n\n  ext = (struct smc_llc_msg_add_link_v2_ext *)(llc_msg + SMC_WR_TX_SIZE);\n\nThe entry is a 72-byte allocation and the extension starts at offset 68, so\next->num_rkeys at offset 94 is already past it. This happens on every\nSMC-Rv2 link addition, whatever the peer sends:\n\n  [    2.490065] BUG: KASAN: slab-out-of-bounds in smc_llc_save_add_link_rkeys+0x333/0x350\n  [    2.490431] Read of size 2 at addr ffff8880056406de by task smctest/106\n  [    2.490709]\n  [    2.490792] CPU: 0 UID: 0 PID: 106 Comm: smctest Not tainted 7.2.0-rc5-p1-g77a5d9d9c99f #32 PREEMPT(lazy)\n  [    2.490795] Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n  [    2.490798] Call Trace:\n  [    2.490803]  <TASK>\n  [    2.490805]  dump_stack_lvl+0x53/0x70\n  [    2.490810]  print_report+0xd0/0x630\n  [    2.490828]  ? __pfx__raw_spin_lock_irqsave+0x10/0x10\n  [    2.490832]  ? smc_llc_save_add_link_rkeys+0x333/0x350\n  [    2.490834]  kasan_report+0xce/0x100\n  [    2.490836]  ? smc_llc_save_add_link_rkeys+0x333/0x350\n  [    2.490837]  smc_llc_save_add_link_rkeys+0x333/0x350\n  [    2.490839]  ? smcr_buf_map_lgr+0x1bf/0x2b0\n  [    2.490844]  smc_llc_cli_add_link+0xca7/0x1e80\n  [    2.490848]  ? smc_llc_wait+0x355/0x810\n  [    2.490850]  ? __pfx_smc_llc_wait+0x10/0x10\n  [    2.490851]  ? __pfx_smc_llc_cli_add_link+0x10/0x10\n  [    2.490853]  ? __pfx_autoremove_wake_function+0x10/0x10\n  [    2.490863]  __smc_connect+0x3f5c/0x4980\n  [    2.490873]  ? __pfx_kernel_connect+0x10/0x10\n  [    2.490888]  ? __pfx___smc_connect+0x10/0x10\n  [    2.490891]  ? release_sock+0x148/0x1d0\n  [    2.490894]  smc_connect+0x42c/0x580\n  [    2.490896]  __sys_connect+0xfc/0x130\n  [    2.490898]  ? __pfx___sys_connect+0x10/0x10\n  [    2.490900]  ? handle_mm_fault+0x1a1/0x430\n  [    2.490908]  __x64_sys_connect+0x6d/0xb0\n  [    2.490909]  ? fpregs_assert_state_consistent+0x56/0xe0\n  [    2.490917]  do_syscall_64+0xf9/0x540\n  [    2.490921]  entry_SYSCALL_64_after_hwframe+0x77/0x7f\n  [    2.490924] RIP: 0033:0x421bb4\n  [    2.490927] Code: ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 80 3d ad 34 09 00 00 74 13 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 4c c3 0f 1f 00 55 48 89 e5 48 83 ec 10 89 55\n  [    2.490929] RSP: 002b:00007ffd473b01a8 EFLAGS: 00000202 ORIG_RAX: 000000000000002a\n  [    2.490935] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000421bb4\n  [    2.490936] RDX: 0000000000000010 RSI: 00007ffd473b01d0 RDI: 0000000000000003\n  [    2.490937] RBP: 0000000000003930 R08: 0000000000000004 R09: 0000000000000000\n  [    2.490938] R10: 00007ffd473b0f98 R11: 0000000000000202 R12: 0000000000000006\n  [    2.490939] R13: 00007ffd473b0f87 R14: 0000000000000003 R15: 00007ffd473b0f90\n  [    2.490940]  </TASK>\n  [    2.490941]\n  [    2.499545] Allocated by task 44:\n  [    2.499693]  kasan_save_stack+0x33/0x60\n  [    2.499860]  kasan_save_track+0x14/0x30\n  [    2.500026]  __kasan_kmalloc+0x8f/0xa0\n  [    2.500190]  __kmalloc_cache_noprof+0x158/0x370\n  [    2.500393]  smc_llc_enqueue+0x72/0x560\n  [    2.500559]  smc_wr_rx_tasklet_fn+0x474/0xa80\n  [    2.500747]  tasklet_action_common+0x20f/0x8a0\n  [    2.500945]  handle_softirqs+0x18e/0x590\n  [    2.501115]  do_softirq+0x3b/0x60\n  [    2.501266]  __local_bh_enable_ip+0x61/0x70\n  [    2.501446]  __alloc_skb+0x732/0x890\n  [    2.501604]  rxe_init_packet+0x16b/0x4f0\n  [    2.501783]  prepare_ack_packet+0xb8/0x830\n  [    2.501962]  rxe_receiver+0x495/0x96e0\n  [    2.502125]  do_work+0x144/0x470\n  [    2.502269]  process_one_work+0x633/0x1030\n  [    2.502450]  worker_thread+0x45b/0xd10\n  [    2.50261\n---truncated---"
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                        "baseScore": 9.8,
                        "baseSeverity": "CRITICAL"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:N - The OOB is reached from SMC-Rv2 LLC ADD_LINK and DELETE_RKEY handling on the RDMA RX path (smc_wr_rx_tasklet_fn→smc_llc_rx_handler→smc_llc_enqueue). CLC is plain TCP and SMC-Rv2/RoCEv2 LLC is IP-routable (UDP/4791), so a remote peer that can reach an AF_SMC listener drives the path.\nAC:L - On SMC-Rv2 links with max_recv_sge==1 (the supported device class this bug exists for), every ADD_LINK reads past the 72-byte qentry regardless of peer contents, and a DELETE_RKEY_V2 with num_rkeys=255 walks up to 255 rkeys off the object; no race or attacker-uncontrollable layout is required.\nPR:N - SMC authenticates nothing. smc_create()/smc_listen() enforce no capabilities, and smc_listen_work() runs the CLC/LLC handshake after TCP accept before accept() returns to userspace, so an unauthenticated network peer needs only reachability to the listener.\nUI:N - The listen worker is queued automatically from smc_tcp_listen_work() for inbound connections, and DELETE_RKEY is processed in the LLC event worker from RDMA completions; no local user action such as mounting a filesystem or opening a file is required.\nS:U - The slab out-of-bounds read and the resulting writes into the link-group rtoken table stay inside the host kernel (kmalloc qentry, lgr->rtokens) and do not cross a VM, IOMMU, or sandbox boundary.\nC:H - smc_llc_save_add_link_rkeys() reads ext->num_rkeys 22 bytes past the 72-byte qentry and then walks up to 255 16-byte rt[] entries of adjacent heap; smc_llc_rmt_delete_rkey() similarly out-of-bounds-reads rkey[9..254]. Per kernel CNA guidance a large heap out-of-bounds read is High.\nI:H - Those out-of-bounds bytes are passed to smc_rtoken_set() (writes rkey/dma_addr into lgr->rtokens) and smc_rtoken_delete() (clears matching rtokens). Adjacent kmalloc-96 spray lets a peer influence the written values, corrupting RDMA targeting used by ib_post_send.\nA:H - KASAN reports slab-out-of-bounds in smc_llc_save_add_link_rkeys on every affected ADD_LINK; a multi-kilobyte walk off a 72-byte object can oops when it hits an unmapped page, and a remote peer can repeat the handshake or DELETE_RKEY at will."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/smc/smc_llc.c"
                    ],
                    "versions": [
                        {
                            "version": "27ef6a9981fe74191849966a6d5e0400a4008ab8",
                            "lessThan": "486c699a8cde82c1d9b4f443eeab4ddf86358cb0",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "27ef6a9981fe74191849966a6d5e0400a4008ab8",
                            "lessThan": "5e5d9e6df677d30a2203d257b5fd8b99814fa607",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "27ef6a9981fe74191849966a6d5e0400a4008ab8",
                            "lessThan": "2d1e7c5aaa3326e95e2058457f172ca99a9a4577",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/smc/smc_llc.c"
                    ],
                    "versions": [
                        {
                            "version": "6.14",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.14",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.50",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.4",
                            "lessThanOrEqual": "7.2.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.3",
                            "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": "6.14",
                                    "versionEndExcluding": "6.18.50"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.14",
                                    "versionEndExcluding": "7.2.4"
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                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.14",
                                    "versionEndExcluding": "7.3"
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            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/486c699a8cde82c1d9b4f443eeab4ddf86358cb0"
                },
                {
                    "url": "https://git.kernel.org/stable/c/5e5d9e6df677d30a2203d257b5fd8b99814fa607"
                },
                {
                    "url": "https://git.kernel.org/stable/c/2d1e7c5aaa3326e95e2058457f172ca99a9a4577"
                }
            ],
            "title": "net/smc: bound the peer rkey counts in SMC-Rv2 LLC messages",
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}