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CVE-2026-99247

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: tracing: Do not initialize tracefs work if tracing is disabled If trace buffer allocation fails during early boot (e.g. in early_trace_init() -> allocate_trace_buffers()), tracing_disabled is left set to 1 and the global trace array events list remains uninitialized. Later during boot, tracer_init_tracefs() (invoked via fs_initcall) queues tracerfs_init_work asynchronously without checking if tracing was disabled. When tracer_init_tracefs_work_func() runs, it calls event_trace_init() and init_tracer_tracefs(&global_trace, NULL) unconditionally. This leads to __find_event_file() dereferencing an uninitialized tr->events list, causing an early boot NULL pointer dereference Oops: BUG: Kernel NULL pointer dereference on read at 0x00000010 Faulting instruction address: 0xc000000000485be0 Oops: Kernel access of bad area, sig: 7 [#1] ... NIP [c000000000485be0] __find_event_file+0x70/0x3c0 LR [c000000000448874] init_tracer_tracefs+0x274/0xc80 Call Trace: init_tracer_tracefs+0x274/0xc80 tracer_init_tracefs_work_func+0x50/0x320 process_one_work+0x1e8/0x5c0 worker_thread+0x1dc/0x3d0 kthread+0x194/0x1b0 start_kernel_thread+0x14/0x18 Check tracing_disabled at the beginning of tracer_init_tracefs_work_func() and return immediately if tracing is disabled or failed to initialize, preventing the crash.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-11-03 12:17:31.190000
Last modified
2026-11-03 12:17:31.190000
View original CVE JSON
{
  "id": "CVE-2026-99247",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-11-03T12:17:31.190",
  "lastModified": "2026-11-03T12:17:31.190",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Do not initialize tracefs work if tracing is disabled\n\nIf trace buffer allocation fails during early boot (e.g.  in\nearly_trace_init() -> allocate_trace_buffers()), tracing_disabled is\nleft set to 1 and the global trace array events list remains\nuninitialized.\n\nLater during boot, tracer_init_tracefs() (invoked via fs_initcall)\nqueues tracerfs_init_work asynchronously without checking if tracing was\ndisabled.  When tracer_init_tracefs_work_func() runs, it calls\nevent_trace_init() and init_tracer_tracefs(&global_trace, NULL)\nunconditionally.  This leads to __find_event_file() dereferencing an\nuninitialized tr->events list, causing an early boot NULL pointer\ndereference Oops:\n\n  BUG: Kernel NULL pointer dereference on read at 0x00000010\n  Faulting instruction address: 0xc000000000485be0\n  Oops: Kernel access of bad area, sig: 7 [#1]\n  ...\n  NIP [c000000000485be0] __find_event_file+0x70/0x3c0\n  LR  [c000000000448874] init_tracer_tracefs+0x274/0xc80\n  Call Trace:\n   init_tracer_tracefs+0x274/0xc80\n   tracer_init_tracefs_work_func+0x50/0x320\n   process_one_work+0x1e8/0x5c0\n   worker_thread+0x1dc/0x3d0\n   kthread+0x194/0x1b0\n   start_kernel_thread+0x14/0x18\n\nCheck tracing_disabled at the beginning of tracer_init_tracefs_work_func()\nand return immediately if tracing is disabled or failed to initialize,\npreventing the crash."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "kernel/trace/trace.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6621a7004684bfcff5af4c8e4d37989941f42a6b",
              "lessThan": "e8665e884e076d894f3eed8b9ea28e37a6448604",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6621a7004684bfcff5af4c8e4d37989941f42a6b",
              "lessThan": "e8cfcd7e60eaa3b0dea4d71c64499604e7081736",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6621a7004684bfcff5af4c8e4d37989941f42a6b",
              "lessThan": "afd38b10b1c6a5c5d6952b15b990596dab9684e6",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6621a7004684bfcff5af4c8e4d37989941f42a6b",
              "lessThan": "813e18881c6472eb229a63180ff42c808e3e949b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6621a7004684bfcff5af4c8e4d37989941f42a6b",
              "lessThan": "7539c61f522ff693d9565a0411386c2236e776cd",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6621a7004684bfcff5af4c8e4d37989941f42a6b",
              "lessThan": "b3b974008388ab59e44d764ba7a63c988fec2524",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "kernel/trace/trace.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.19",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.19",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.161",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.115",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.59",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.13",
              "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/7539c61f522ff693d9565a0411386c2236e776cd",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/813e18881c6472eb229a63180ff42c808e3e949b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/afd38b10b1c6a5c5d6952b15b990596dab9684e6",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b3b974008388ab59e44d764ba7a63c988fec2524",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e8665e884e076d894f3eed8b9ea28e37a6448604",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e8cfcd7e60eaa3b0dea4d71c64499604e7081736",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}