{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-90190",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2026-90190"
  ],
  "published": "2026-09-17T16:10:40Z",
  "summary": "null_blk: use DEFINE_MUTEX for the file-scope mutex",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnull_blk: use DEFINE_MUTEX for the file-scope mutex\n\nIn null_init(), mutex_init(&lock) currently happens after\nconfigfs_register_subsystem(), which exposes the nullb subsystem to\nuserspace. A racing mkdir() into /sys/kernel/config/nullb/ can reach\nnull_find_dev_by_name() -> mutex_lock(&lock) before the mutex is\ninitialized, trigger warning:\n\n[  123.137788] DEBUG_LOCKS_WARN_ON(lock->magic != lock)\n[  123.137796] WARNING: kernel/locking/mutex.c:159 at mutex_lock+0x171/0x1c0, CPU#13: mkdir/1301\n[  123.140090] Modules linked in: null_blk(+) nft_fib_inet nft_fib_ipv4\n......\n[  123.154926] Call Trace:\n[  123.155172]  <TASK>\n[  123.155419]  ? __pfx_mutex_lock+0x10/0x10\n[  123.156181]  ? __pfx__raw_spin_lock+0x10/0x10\n[  123.156571]  nullb_group_make_group+0x20/0x100 [null_blk]\n[  123.157011]  configfs_mkdir+0x47b/0xc70\n[  123.157337]  ? __pfx_configfs_mkdir+0x10/0x10\n[  123.157719]  ? may_create_dentry+0x242/0x2e0\n[  123.158061]  vfs_mkdir+0x2a9/0x6c0\n[  123.158352]  filename_mkdirat+0x3dc/0x500\n[  123.158710]  ? __pfx_filename_mkdirat+0x10/0x10\n[  123.159070]  ? strncpy_from_user+0x3a/0x1d0\n[  123.159413]  __x64_sys_mkdir+0x6b/0x90\n[  123.159760]  do_syscall_64+0xea/0x600\n\nReplace the runtime mutex_init(&lock) with a static DEFINE_MUTEX(lock)\ndeclaration to fix this issue.",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.188",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-90190"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/f9f4ca45c770b7eec83fea6c9b727b26e691b513"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/349903f7ee72f7ac5b7a98840d701b2082d140a3"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/0a8c2f7b95981913ac370683e34db4906970c210"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c7dea90c9b4ef1dfbd2e4df36de180c76fd7c33c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/234117949da3b3f9705a21b66094f9f30bbe681d"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/017dac7670909eaea3eb36e6b3b5a8be9ce0a14d"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-09-17T16:10:40Z"
  }
}
