CVE-2026-98815

{
  "id": "CVE-2026-98815",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-18T16:17:35.640",
  "lastModified": "2026-10-26T07:17:11.483",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnvme: fix cdev lifetime\n\nSashiko bot reported a potential problem for the cdev lifetime in [0]\n- the code there is heavily based on the NVMe code.\n\nCurrently the NS head .open and .release file_operations methods take and\nput a reference to the nvme_ns_head to ensure that this structure does not\ndisappear while we open fds for that cdev.\n\nIn multipath mode, when we teardown the NS head, we call nvme_cdev_del() ->\ncdev_device_del() -> cdev_del(). However after cdev_del() returns, cdevs\nalready open will remain and their fops will still be callable. As such,\nwe can still reference the cdev after the nvme_ns_head reference count\ndrops to 0 (and is freed).\n\nThis can be shown with an application which delays between opening the cdev\nand issuing the ioctl while the NS head is being torn down:\n\n# ./ioctl_file /dev/ng1n1 &\n# waiting 10 seconds ....\n\n# ./ini_nvme_teardown.sh\n[   21.221718] nvme nvme1: Removing ctrl: NQN \"nvme-test-target\"\n[   21.274609] nvme nvme2: Removing ctrl: NQN \"nvme-test-target\"\n# now going to issue ioctl ....\n[   26.549285] ==================================================================\n[   26.550841] BUG: KASAN: slab-use-after-free in cdev_put.part.0+0x3d/0x40\n[   26.552352] Read of size 8 at addr ffff88811e7fa170 by task ioctl_file/237\n[   26.553805]\n[   26.554227] CPU: 3 UID: 0 PID: 237 Comm: ioctl_file Not tainted 7.2.0-rc1-00004-g6852a10e32d4 #921 PREEMPT(lazy)\n[   26.554236] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n[   26.554241] Call Trace:\n[   26.554245]  <TASK>\n[   26.554248]  dump_stack_lvl+0x68/0xa0\n[   26.554266]  print_report+0x10d/0x5d0\n[   26.554276]  ? __virt_addr_valid+0x21d/0x3f0\n[   26.554287]  ? cdev_put.part.0+0x3d/0x40\n[   26.554292]  kasan_report+0x96/0xd0\n[   26.554300]  ? cdev_put.part.0+0x3d/0x40\n[   26.554307]  cdev_put.part.0+0x3d/0x40\n[   26.554313]  __fput+0x7bc/0xa70\n[   26.554322]  fput_close_sync+0xd8/0x190\n[   26.554328]  ? __pfx_fput_close_sync+0x10/0x10\n[   26.554337]  __x64_sys_close+0x79/0xd0\n[   26.554344]  do_syscall_64+0x117/0x6b0\n[   26.554351]  entry_SYSCALL_64_after_hwframe+0x77/0x7f\n[   26.554358] RIP: 0033:0x7f938c067727\n[   26.554364] Code: 48 89 fa 4c 89 df e8 28 ad 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5bf\n[   26.554369] RSP: 002b:00007fff49f05980 EFLAGS: 00000202 ORIG_RAX: 0000000000000003\n[   26.554376] RAX: ffffffffffffffda RBX: 00007f938bfd7780 RCX: 00007f938c067727\n[   26.554380] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003\n[   26.554383] RBP: 00007fff49f05a10 R08: 0000000000000000 R09: 0000000000000000\n[   26.554386] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000\n[   26.554389] R13: 00007fff49f05b40 R14: 00007f938c207000 R15: 000055c148471d78\n[   26.554397]  </TASK>\n[   26.554399]\n[   26.575612] Allocated by task 100:\n[   26.575871]  kasan_save_stack+0x24/0x50\n[   26.576157]  kasan_save_track+0x14/0x30\n[   26.576418]  __kasan_kmalloc+0x7f/0x90\n[   26.576668]  __kmalloc_noprof+0x281/0x6c0\n[   26.576938]  nvme_alloc_ns+0x7f7/0x3170\n[   26.577206]  nvme_scan_ns+0x508/0x880\n[   26.577449]  async_run_entry_fn+0x8c/0x350\n[   26.577723]  process_scheduled_works+0xb6f/0x1a00\n[   26.578034]  worker_thread+0x4ad/0xb40\n[   26.578283]  kthread+0x34f/0x450\n[   26.578501]  ret_from_fork+0x563/0x800\n[   26.578752]  ret_from_fork_asm+0x1a/0x30\n[   26.579012]\n[   26.579124] Freed by task 237:\n[   26.579335]  kasan_save_stack+0x24/0x50\n[   26.579596]  kasan_save_track+0x14/0x30\n[   26.579855]  kasan_save_free_info+0x3a/0x60\n[   26.580131]  __kasan_slab_free+0x43/0x70\n[   26.580388]  kfree+0x321/0x500\n[   26.580591]  nvme_ns_head_chr_release+0x39/0x50\n[   26.580883]  __fput+0x352/0xa70\n[   26.581095]  fput_close_sync+0xd8/0x190\n[   26.581350]  __x64_sys_close+0x79/0xd0\n[   26.581595]  do_syscall_64+0x117/0x6b0\n[   26.581842]  entry_SYSCAL\n---truncated---"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/nvme/host/core.c",
            "drivers/nvme/host/multipath.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "2637baed78010eeaae274feb5b99ce90933fadfb",
              "lessThan": "98b09ad7934482e64db4b4477d91e3bbf43adf4c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2637baed78010eeaae274feb5b99ce90933fadfb",
              "lessThan": "9952f3882ecba709092379b71e02b09762b26f96",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/nvme/host/core.c",
            "drivers/nvme/host/multipath.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.13",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.13",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.10",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/98b09ad7934482e64db4b4477d91e3bbf43adf4c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9952f3882ecba709092379b71e02b09762b26f96",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}