{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2025-68335",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2025-68335"
  ],
  "published": "2025-12-22T16:14:44Z",
  "summary": "comedi: pcl818: fix null-ptr-deref in pcl818_ai_cancel()",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncomedi: pcl818: fix null-ptr-deref in pcl818_ai_cancel()\n\nSyzbot identified an issue [1] in pcl818_ai_cancel(), which stems from\nthe fact that in case of early device detach via pcl818_detach(),\nsubdevice dev->read_subdev may not have initialized its pointer to\n&struct comedi_async as intended. Thus, any such dereferencing of\n&s->async->cmd will lead to general protection fault and kernel crash.\n\nMitigate this problem by removing a call to pcl818_ai_cancel() from\npcl818_detach() altogether. This way, if the subdevice setups its\nsupport for async commands, everything async-related will be\nhandled via subdevice's own ->cancel() function in\ncomedi_device_detach_locked() even before pcl818_detach(). If no\nsupport for asynchronous commands is provided, there is no need\nto cancel anything either.\n\n[1] Syzbot crash:\nOops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] SMP KASAN PTI\nKASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]\nCPU: 1 UID: 0 PID: 6050 Comm: syz.0.18 Not tainted syzkaller #0 PREEMPT(full)\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025\nRIP: 0010:pcl818_ai_cancel+0x69/0x3f0 drivers/comedi/drivers/pcl818.c:762\n...\nCall Trace:\n <TASK>\n pcl818_detach+0x66/0xd0 drivers/comedi/drivers/pcl818.c:1115\n comedi_device_detach_locked+0x178/0x750 drivers/comedi/drivers.c:207\n do_devconfig_ioctl drivers/comedi/comedi_fops.c:848 [inline]\n comedi_unlocked_ioctl+0xcde/0x1020 drivers/comedi/comedi_fops.c:2178\n vfs_ioctl fs/ioctl.c:51 [inline]\n __do_sys_ioctl fs/ioctl.c:597 [inline]\n...",
  "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": "6.1.160",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2025-68335"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/b2a5b172dc05be6c4f2c5542c1bbc6b14d60ff16"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/935ad4b3c325c24fff2c702da403283025ffc722"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/88d99ca5adbd01ff088f5fb2ddeba5755e085e52"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/5caa40e7c6a43e08e3574f990865127705c22861"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d948c53dec36dafe182631457597c49c1f1df5ea"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/877adccfacb32687b90714a27cfb09f444fdfa16"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/a51f025b5038abd3d22eed2ede4cd46793d89565"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-05-12T04:54:46Z"
  }
}