{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2025-21983",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2025-21983"
  ],
  "published": "2025-04-01T15:46:27Z",
  "summary": "mm/slab/kvfree_rcu: Switch to WQ_MEM_RECLAIM wq",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/slab/kvfree_rcu: Switch to WQ_MEM_RECLAIM wq\n\nCurrently kvfree_rcu() APIs use a system workqueue which is\n\"system_unbound_wq\" to driver RCU machinery to reclaim a memory.\n\nRecently, it has been noted that the following kernel warning can\nbe observed:\n\n<snip>\nworkqueue: WQ_MEM_RECLAIM nvme-wq:nvme_scan_work is flushing !WQ_MEM_RECLAIM events_unbound:kfree_rcu_work\n  WARNING: CPU: 21 PID: 330 at kernel/workqueue.c:3719 check_flush_dependency+0x112/0x120\n  Modules linked in: intel_uncore_frequency(E) intel_uncore_frequency_common(E) skx_edac(E) ...\n  CPU: 21 UID: 0 PID: 330 Comm: kworker/u144:6 Tainted: G            E      6.13.2-0_g925d379822da #1\n  Hardware name: Wiwynn Twin Lakes MP/Twin Lakes Passive MP, BIOS YMM20 02/01/2023\n  Workqueue: nvme-wq nvme_scan_work\n  RIP: 0010:check_flush_dependency+0x112/0x120\n  Code: 05 9a 40 14 02 01 48 81 c6 c0 00 00 00 48 8b 50 18 48 81 c7 c0 00 00 00 48 89 f9 48 ...\n  RSP: 0018:ffffc90000df7bd8 EFLAGS: 00010082\n  RAX: 000000000000006a RBX: ffffffff81622390 RCX: 0000000000000027\n  RDX: 00000000fffeffff RSI: 000000000057ffa8 RDI: ffff88907f960c88\n  RBP: 0000000000000000 R08: ffffffff83068e50 R09: 000000000002fffd\n  R10: 0000000000000004 R11: 0000000000000000 R12: ffff8881001a4400\n  R13: 0000000000000000 R14: ffff88907f420fb8 R15: 0000000000000000\n  FS:  0000000000000000(0000) GS:ffff88907f940000(0000) knlGS:0000000000000000\n  CR2: 00007f60c3001000 CR3: 000000107d010005 CR4: 00000000007726f0\n  PKRU: 55555554\n  Call Trace:\n   <TASK>\n   ? __warn+0xa4/0x140\n   ? check_flush_dependency+0x112/0x120\n   ? report_bug+0xe1/0x140\n   ? check_flush_dependency+0x112/0x120\n   ? handle_bug+0x5e/0x90\n   ? exc_invalid_op+0x16/0x40\n   ? asm_exc_invalid_op+0x16/0x20\n   ? timer_recalc_next_expiry+0x190/0x190\n   ? check_flush_dependency+0x112/0x120\n   ? check_flush_dependency+0x112/0x120\n   __flush_work.llvm.1643880146586177030+0x174/0x2c0\n   flush_rcu_work+0x28/0x30\n   kvfree_rcu_barrier+0x12f/0x160\n   kmem_cache_destroy+0x18/0x120\n   bioset_exit+0x10c/0x150\n   disk_release.llvm.6740012984264378178+0x61/0xd0\n   device_release+0x4f/0x90\n   kobject_put+0x95/0x180\n   nvme_put_ns+0x23/0xc0\n   nvme_remove_invalid_namespaces+0xb3/0xd0\n   nvme_scan_work+0x342/0x490\n   process_scheduled_works+0x1a2/0x370\n   worker_thread+0x2ff/0x390\n   ? pwq_release_workfn+0x1e0/0x1e0\n   kthread+0xb1/0xe0\n   ? __kthread_parkme+0x70/0x70\n   ret_from_fork+0x30/0x40\n   ? __kthread_parkme+0x70/0x70\n   ret_from_fork_asm+0x11/0x20\n   </TASK>\n  ---[ end trace 0000000000000000 ]---\n<snip>\n\nTo address this switch to use of independent WQ_MEM_RECLAIM\nworkqueue, so the rules are not violated from workqueue framework\npoint of view.\n\nApart of that, since kvfree_rcu() does reclaim memory it is worth\nto go with WQ_MEM_RECLAIM type of wq because it is designed for\nthis purpose.",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:13",
        "name": "linux"
      },
      "versions": [
        "1:6.12.19-1+rpt1~bpo12+1",
        "1:6.12.19-1+rpt1"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.12.19+rpt-rpi-2712",
            "binary_version": "1:6.12.19-1+rpt1~bpo12+1"
          },
          {
            "binary_name": "linux-image-6.12.19+rpt-rpi-v6",
            "binary_version": "1:6.12.19-1+rpt1~bpo12+1"
          },
          {
            "binary_name": "linux-image-6.12.19+rpt-rpi-v7",
            "binary_version": "1:6.12.19-1+rpt1~bpo12+1"
          },
          {
            "binary_name": "linux-image-6.12.19+rpt-rpi-v7l",
            "binary_version": "1:6.12.19-1+rpt1~bpo12+1"
          },
          {
            "binary_name": "linux-image-6.12.19+rpt-rpi-v8",
            "binary_version": "1:6.12.19-1+rpt1~bpo12+1"
          },
          {
            "binary_name": "linux-image-6.12.19+rpt-rpi-2712",
            "binary_version": "1:6.12.19-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.19+rpt-rpi-v6",
            "binary_version": "1:6.12.19-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.19+rpt-rpi-v7",
            "binary_version": "1:6.12.19-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.19+rpt-rpi-v7l",
            "binary_version": "1:6.12.19-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.19+rpt-rpi-v8",
            "binary_version": "1:6.12.19-1+rpt1"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.12.19-1+rpt1~bpo12+1": {
            "linux_commit": "121c2c384b9c2f4790ffb31b2cd25c7d75c8fda0",
            "upstream_version": "6.12.19",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.12.20"
          },
          "1:6.12.19-1+rpt1": {
            "linux_commit": "121c2c384b9c2f4790ffb31b2cd25c7d75c8fda0",
            "upstream_version": "6.12.19",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.12.20"
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2025-21983"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/a74979dce9e9c61f6d797c3761020252c4d8dc63"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/656e35bf66a11e1adde44c4c12050086dc39f241"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/dfd3df31c9db752234d7d2e09bef2aeabb643ce4"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-05-12T04:54:46Z"
  }
}