{
  "cveId": "CVE-2026-80981",
  "url": "https://patchblox.com/security/cve/CVE-2026-80981",
  "summary": "CVE-2026-80981 is fixed in linux on 1 platform by DEBIAN-CVE-2026-80981 (version 7.2.6-1), released September 23, 2026. It is not reported as exploited. Patch Radar priority: Urgent.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  net/smc: fix use-after-free of the LLC qentry in...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  net/smc: fix use-after-free of the LLC qentry in smc_llc_srv_add_link()  smc_llc_srv_add_link() keeps add_llc pointing into the queue entry:    add_llc = \u0026qentry-\u003Emsg.add_link;\t\t\tsmc_llc.c:1482   ...   smc_llc_save_add_link_info(link_new, add_llc);\tsmc_llc.c:1494   smc_llc_flow_qentry_del(\u0026lgr-\u003Ellc_flow_lcl);\t\tsmc_llc.c:1495   ...   u8 *llc_msg = smc_link_shared_v2_rxbuf(link) ? \t(u8 *)lgr-\u003Ewr_rx_buf_v2 : (u8 *)add_llc;\tsmc_llc.c:1504   smc_llc_save_add_link_rkeys(link, link_new, llc_msg);\tsmc_llc.c:1506  smc_llc_flow_qentry_del() kfree()s the entry, so on a link without a shared v2 receive buffer the pointer handed to smc_llc_save_add_link_rkeys() is already freed. Before the Fixes: commit that branch always used lgr-\u003Ewr_rx_buf_v2 and add_llc was not used after the free.  Reproduced on an unpatched tree over rxe, with KASAN, kasan_multi_shot and a link forced to max_recv_sge == 1: the entry is freed and read by the same call, and the freeing frame is smc_llc_srv_add_link() itself.    [    2.523161] BUG: KASAN: slab-use-after-free in smc_llc_save_add_link_rkeys\u002B0x333/0x350   [    2.523499] Read of size 2 at addr ffff8880052194de by task kworker/0:1/11   [    2.523789]   [    2.523862] CPU: 0 UID: 0 PID: 11 Comm: kworker/0:1 Not tainted 7.2.0-rc5-p0-g2c9dd296545d #35 PREEMPT(lazy)   [    2.523865] Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX \u002B PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014   [    2.523866] Workqueue: smc_hs_wq smc_listen_work   [    2.523869] Call Trace:   [    2.523870]  \u003CTASK\u003E   [    2.523871]  dump_stack_lvl\u002B0x53/0x70   [    2.523872]  print_report\u002B0xd0/0x630   [    2.523874]  ? __pfx__raw_spin_lock_irqsave\u002B0x10/0x10   [    2.523876]  ? smc_llc_save_add_link_rkeys\u002B0x333/0x350   [    2.523878]  kasan_report\u002B0xce/0x100   [    2.523879]  ? smc_llc_save_add_link_rkeys\u002B0x333/0x350   [    2.523881]  smc_llc_save_add_link_rkeys\u002B0x333/0x350   [    2.523883]  ? smcr_buf_reg_lgr\u002B0x2a4/0x660   [    2.523885]  smc_llc_srv_add_link\u002B0xaa2/0x1e50   [    2.523888]  ? _printk\u002B0xba/0xf0   [    2.523897]  ? __pfx_smc_llc_srv_add_link\u002B0x10/0x10   [    2.523899]  ? down_write\u002B0xb0/0x130   [    2.523903]  ? __pfx_down_write\u002B0x10/0x10   [    2.523905]  smc_listen_work\u002B0x489e/0x4d00   [    2.523907]  ? kmem_cache_free\u002B0x1c6/0x3a0   [    2.523911]  ? __pfx_smc_listen_work\u002B0x10/0x10   [    2.523913]  ? release_sock\u002B0x148/0x1d0   [    2.523915]  ? smc_tcp_listen_work\u002B0xb4f/0xfc0   [    2.523917]  ? _raw_spin_lock_irq\u002B0x80/0xe0   [    2.523918]  ? __pfx__raw_spin_lock_irq\u002B0x10/0x10   [    2.523920]  process_one_work\u002B0x633/0x1030   [    2.523922]  ? assign_work\u002B0x11d/0x370   [    2.523924]  worker_thread\u002B0x45b/0xd10   [    2.523926]  ? __pfx_worker_thread\u002B0x10/0x10   [    2.523928]  ? __pfx_worker_thread\u002B0x10/0x10   [    2.523929]  kthread\u002B0x2c6/0x3b0   [    2.523931]  ? recalc_sigpending\u002B0x15c/0x1e0   [    2.523934]  ? __pfx_kthread\u002B0x10/0x10   [    2.523935]  ret_from_fork\u002B0x36e/0x5a0   [    2.523937]  ? __pfx_ret_from_fork\u002B0x10/0x10   [    2.523938]  ? __switch_to\u002B0x572/0xdd0   [    2.523943]  ? __pfx_kthread\u002B0x10/0x10   [    2.523944]  ret_from_fork_asm\u002B0x1a/0x30   [    2.523947]  \u003C/TASK\u003E   [    2.523948]   [    2.531253] Allocated by task 48:   [    2.531399]  kasan_save_stack\u002B0x33/0x60   [    2.531570]  kasan_save_track\u002B0x14/0x30   [    2.531737]  __kasan_kmalloc\u002B0x8f/0xa0   [    2.531905]  __kmalloc_cache_noprof\u002B0x158/0x370   [    2.532100]  smc_llc_enqueue\u002B0x72/0x560   [    2.532268]  smc_wr_rx_tasklet_fn\u002B0x474/0xa80   [    2.532491]  tasklet_action_common\u002B0x20f/0x8a0   [    2.532714]  handle_softirqs\u002B0x18e/0x590   [    2.532886]  do_softirq\u002B0x3b/0x60   [    2.533036]  __local_bh_enable_ip\u002B0x61/0x70   [    2.533221]  __alloc_skb\u002B0x732/0x890   [    2.533384]  rxe_init_packet\u002B0x16b/0x4f0   [    2.533567]  prepare_ack_packet\u002B0xb8/0x830   [    2.533760]  rxe_receiver\u002B0x495/0x96e0   [    2.533933]  do_work\u002B0x144/0x470   [    2 ---truncated---",
  "published": "2026-09-11T20:19:04Z",
  "severity": "critical",
  "cvss": 9.8,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
  "epss": 0.00631,
  "epssPercentile": 0.50532,
  "priority": "Urgent",
  "priorityTier": 2,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.6-1",
      "fix": "DEBIAN-CVE-2026-80981",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-80981",
      "released": "2026-09-23T19:19:02Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-09T07:25:28Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}