CVE-2025-68257: comedi: check device's attached status in compat ioctls
In the Linux kernel, the following vulnerability has been resolved:
comedi: check device's attached status in compat ioctls
Syzbot identified an issue [1] that crashes kernel, seemingly due to unexistent callback dev->getvalidroutes(). By all means, this should not occur as said callback must always be set to getzerovalidroutes() in comedidevicepostconfig().
As the crash seems to appear exclusively in i386 kernels, at least, judging from [1] reports, the blame lies with compat versions of standard IOCTL handlers. Several of them are modified and do not use comediunlockedioctl(). While functionality of these ioctls essentially copy their original versions, they do not have required sanity check for device's attached status. This, in turn, leads to a possibility of calling select IOCTLs on a device that has not been properly setup, even via COMEDIDEVCONFIG.
Doing so on unconfigured devices means that several crucial steps are missed, for instance, specifying dev->getvalidroutes() callback.
Fix this somewhat crudely by ensuring device's attached status before performing any ioctls, improving logic consistency between modern and compat functions.
[1] Syzbot report: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... CR2: ffffffffffffffd6 CR3: 000000006c717000 CR4: 0000000000352ef0 Call Trace: <TASK> getvalidroutes drivers/comedi/comedifops.c:1322 [inline] parseinsn+0x78c/0x1970 drivers/comedi/comedifops.c:1401 doinsnlistioctl+0x272/0x700 drivers/comedi/comedifops.c:1594 compatinsnlist drivers/comedi/comedifops.c:3208 [inline] comedicompatioctl+0x810/0x990 drivers/comedi/comedifops.c:3273 docompatsysioctl fs/ioctl.c:695 [inline] secompatsysioctl fs/ioctl.c:638 [inline] ia32compatsysioctl+0x242/0x370 fs/ioctl.c:638 dosyscall32irqson arch/x86/entry/syscall32.c:83 [inline] ...
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
ubuntu/linux-aws-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1103.110~20.04.1 - Upgrade
Upgrade
ubuntu/linux-azure-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1110.119~20.04.1 - Upgrade
Upgrade
ubuntu/linux-gcp-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1103.112~20.04.1 - Upgrade
Upgrade
ubuntu/linux-hwe-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-173.183~20.04.1 - Upgrade
Upgrade
ubuntu/linux-ibm-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1097.100~20.04.1 - Upgrade
Upgrade
ubuntu/linux-intel-iotg-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1098.104~20.04.1 - Upgrade
Upgrade
ubuntu/linux-lowlatency-hwe-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-173.183~20.04.1 - Upgrade
Upgrade
ubuntu/linux-nvidia-tegra-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1055.55~20.04.1 - Upgrade
Upgrade
ubuntu/linux-oracle-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1100.106~20.04.1 - Upgrade
Upgrade
ubuntu/linux-riscv-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1097.101~20.04.1 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 5.15.0-173.183 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 5.15.0-1103.110 - Upgrade
Upgrade
ubuntu/linux-aws-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1052.55~22.04.1 - Upgrade
Upgrade
ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 5.15.0-1109.118 - Upgrade
Upgrade
ubuntu/linux-azure-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1059.65~22.04.1 - Upgrade
Upgrade
ubuntu/linux-azure-fdeto a version that resolves this vulnerability.Fixed in 5.15.0-1109.118.1 - Upgrade
Upgrade
ubuntu/linux-azure-fde-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1058.65~22.04.1 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 5.15.0-1103.112 - Upgrade
Upgrade
ubuntu/linux-gcp-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1054.57~22.04.1 - Upgrade
Upgrade
ubuntu/linux-gketo a version that resolves this vulnerability.Fixed in 5.15.0-1099.105 - Upgrade
Upgrade
ubuntu/linux-gkeopto a version that resolves this vulnerability.Fixed in 5.15.0-1086.94 - Upgrade
Upgrade
ubuntu/linux-hwe-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-110.110~22.04.1 - Upgrade
Upgrade
ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 5.15.0-1097.100 - Upgrade
Upgrade
ubuntu/linux-ibm-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1051.51~22.04.1 - Upgrade
Upgrade
ubuntu/linux-intel-iotgto a version that resolves this vulnerability.Fixed in 5.15.0-1098.104 - Upgrade
Upgrade
ubuntu/linux-kvmto a version that resolves this vulnerability.Fixed in 5.15.0-1095.100 - Upgrade
Upgrade
ubuntu/linux-lowlatencyto a version that resolves this vulnerability.Fixed in 5.15.0-173.183 - Upgrade
Upgrade
ubuntu/linux-lowlatency-hwe-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-110.110.1~22.04.1 - Upgrade
Upgrade
ubuntu/linux-nvidiato a version that resolves this vulnerability.Fixed in 5.15.0-1098.99 - Upgrade
Upgrade
ubuntu/linux-nvidia-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1051.54~22.04.1 - Upgrade
Upgrade
ubuntu/linux-nvidia-tegrato a version that resolves this vulnerability.Fixed in 5.15.0-1055.55 - Upgrade
Upgrade
ubuntu/linux-nvidia-tegra-igxto a version that resolves this vulnerability.Fixed in 5.15.0-1044.44 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 5.15.0-1100.106 - Upgrade
Upgrade
ubuntu/linux-oracle-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1049.50~22.04.1 - Upgrade
Upgrade
ubuntu/linux-raspito a version that resolves this vulnerability.Fixed in 5.15.0-1097.100 - Upgrade
Upgrade
ubuntu/linux-riscv-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-110.110~22.04.1 - Upgrade
Upgrade
ubuntu/linux-xilinx-zynqmpto a version that resolves this vulnerability.Fixed in 5.15.0-1067.71 - Upgrade
Upgrade
ubuntu/linux-bluefieldto a version that resolves this vulnerability.Fixed in 5.15.0-1086.88 - Upgrade
Upgrade
ubuntu/linux-intel-iot-realtimeto a version that resolves this vulnerability.Fixed in 5.15.0-1094.96 - Upgrade
Upgrade
ubuntu/linux-realtimeto a version that resolves this vulnerability.Fixed in 5.15.0-1102.111 - Upgrade
Upgrade
ubuntu/linux-realtime-6.8to a version that resolves this vulnerability.Fixed in 6.8.1-1047.48~22.04.1 - Upgrade
Upgrade
ubuntu/linux-aws-fipsto a version that resolves this vulnerability.Fixed in 5.15.0-1103.110+fips1 - Upgrade
Upgrade
ubuntu/linux-azure-fipsto a version that resolves this vulnerability.Fixed in 5.15.0-1109.118+fips1 - Upgrade
Upgrade
ubuntu/linux-fipsto a version that resolves this vulnerability.Fixed in 5.15.0-173.183+fips1 - Upgrade
Upgrade
ubuntu/linux-gcp-fipsto a version that resolves this vulnerability.Fixed in 5.15.0-1103.112+fips1 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 6.8.0-110.110 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 6.8.0-1052.55 - Upgrade
Upgrade
ubuntu/linux-aws-6.17to a version that resolves this vulnerability.Fixed in 6.17.0-1009.9~24.04.2 - Upgrade
Upgrade
ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 6.8.0-1054.60 - Upgrade
Upgrade
ubuntu/linux-azure-6.17to a version that resolves this vulnerability.Fixed in 6.17.0-1010.10~24.04.1 - Upgrade
Upgrade
ubuntu/linux-azure-fdeto a version that resolves this vulnerability.Fixed in 6.8.0-1058.65 - Upgrade
Upgrade
ubuntu/linux-azure-nvidiato a version that resolves this vulnerability.Fixed in 6.8.0-1039.42 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 6.8.0-1054.57 - Upgrade
Upgrade
ubuntu/linux-gcp-6.17to a version that resolves this vulnerability.Fixed in 6.17.0-1009.9~24.04.3 - Upgrade
Upgrade
ubuntu/linux-gketo a version that resolves this vulnerability.Fixed in 6.8.0-1050.56 - Upgrade
Upgrade
ubuntu/linux-gkeopto a version that resolves this vulnerability.Fixed in 6.8.0-1037.40 - Upgrade
Upgrade
ubuntu/linux-hwe-6.17to a version that resolves this vulnerability.Fixed in 6.17.0-19.19~24.04.2 - Upgrade
Upgrade
ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 6.8.0-1051.51 - Upgrade
Upgrade
ubuntu/linux-lowlatencyto a version that resolves this vulnerability.Fixed in 6.8.0-110.110.1 - Upgrade
Upgrade
ubuntu/linux-nvidiato a version that resolves this vulnerability.Fixed in 6.8.0-1051.54 - Upgrade
Upgrade
ubuntu/linux-nvidia-6.17to a version that resolves this vulnerability.Fixed in 6.17.0-1018.18 - Upgrade
Upgrade
ubuntu/linux-nvidia-lowlatencyto a version that resolves this vulnerability.Fixed in 6.8.0-1051.54.1 - Upgrade
Upgrade
ubuntu/linux-nvidia-tegrato a version that resolves this vulnerability.Fixed in 6.8.0-1022.22 - Upgrade
Upgrade
ubuntu/linux-oem-6.17to a version that resolves this vulnerability.Fixed in 6.17.0-1017.17 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 6.8.0-1049.50 - Upgrade
Upgrade
ubuntu/linux-oracle-6.17to a version that resolves this vulnerability.Fixed in 6.17.0-1009.9~24.04.1 - Upgrade
Upgrade
ubuntu/linux-raspito a version that resolves this vulnerability.Fixed in 6.8.0-1052.56 - Upgrade
Upgrade
ubuntu/linux-riscv-6.17to a version that resolves this vulnerability.Fixed in 6.17.0-19.19.1~24.04.1 - Upgrade
Upgrade
ubuntu/linux-xilinxto a version that resolves this vulnerability.Fixed in 6.8.0-1028.29 - Upgrade
Upgrade
ubuntu/linux-bluefieldto a version that resolves this vulnerability.Fixed in 6.8.0-1017.21 - Upgrade
Upgrade
ubuntu/linux-raspi-realtimeto a version that resolves this vulnerability.Fixed in 6.8.0-2042.43 - Upgrade
Upgrade
ubuntu/linux-realtimeto a version that resolves this vulnerability.Fixed in 6.8.1-1047.48 - Upgrade
Upgrade
ubuntu/linux-realtime-6.17to a version that resolves this vulnerability.Fixed in 6.17.0-1008.9~24.04.1 - Upgrade
Upgrade
ubuntu/linux-aws-fipsto a version that resolves this vulnerability.Fixed in 6.8.0-1052.55+fips1 - Upgrade
Upgrade
ubuntu/linux-azure-fipsto a version that resolves this vulnerability.Fixed in 6.8.0-1053.59+fips1 - Upgrade
Upgrade
ubuntu/linux-fipsto a version that resolves this vulnerability.Fixed in 6.8.0-110.110+fips2 - Upgrade
Upgrade
ubuntu/linux-gcp-fipsto a version that resolves this vulnerability.Fixed in 6.8.0-1054.57+fips1 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 6.17.0-19.19 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 6.17.0-1009.9 - Upgrade
Upgrade
ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 6.17.0-1010.10 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 6.17.0-1009.9 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 6.17.0-1009.9 - Upgrade
Upgrade
ubuntu/linux-raspito a version that resolves this vulnerability.Fixed in 6.17.0-1010.10 - Upgrade
Upgrade
ubuntu/linux-realtimeto a version that resolves this vulnerability.Fixed in 6.17.0-1008.9 - Upgrade
Upgrade
ubuntu/linux-riscvto a version that resolves this vulnerability.Fixed in 6.17.0-19.19.1 - Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.1.176-1Fixed in 6.1.190-1Fixed in 6.12.107-1Fixed in 6.12.116-1Fixed in 7.2.15-1Fixed in 7.3.4-1 - Compensating control
Update the Linux Comedi compat ioctl handlers to verify the device's attached status before performing any ioctls, preventing operations on unconfigured devices.
Event History
Frequently Asked Questions
What is the severity of CVE-2025-68257?
CVE-2025-68257 has been rated with medium severity due to potential crashes in the Linux kernel.
How do I fix CVE-2025-68257?
To fix CVE-2025-68257, ensure you upgrade to the latest version of the Linux kernel that addresses this vulnerability.
What systems are affected by CVE-2025-68257?
CVE-2025-68257 affects the Linux kernel, particularly on i386 architecture systems.
What is the impact of CVE-2025-68257?
The impact of CVE-2025-68257 includes potential kernel crashes due to an issue with the device's attached status in compat ioctls.
Who discovered CVE-2025-68257?
CVE-2025-68257 was identified by the Syzbot security analysis tool.