Findings

CVE-2025-21694

In the Linux kernel, the following vulnerability has been resolved: fs/proc: fix softlockup in __read_vmcore (part 2) Since commit 5cbcb62dddf5 ("fs/proc: fix softlock…

Published Feb 12, 2025 · updated Oct 15, 2026 · linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: fs/proc: fix softlockup in __read_vmcore (part 2) Since commit 5cbcb62dddf5 ("fs/proc: fix softlockup in __read_vmcore") the number of softlockups in __read_vmcore at kdump time have gone down, but they still happen sometimes. In a memory constrained environment like the kdump image, a softlockup is not just a harmless message, but it can interfere with things like RCU freeing memory, causing the crashdump to get stuck. The second loop in __read_vmcore has a lot more opportunities for natural sleep points, like scheduling out while waiting for a data write to happen, but apparently that is not always enough. Add a cond_resched() to the second loop in __read_vmcore to (hopefully) get rid of the softlockups.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Feb 12, 2025 · NIST NVD

    Detected

    In the Linux kernel, the following vulnerability has been resolved: fs/proc: fix softlockup in __read_vmcore (part 2) Since commit 5cbcb62dddf5 ("fs/proc: fix softlockup in __read_vmcore") the number of softlockups in __read_vmcore at kdump time have gone down, but they still happen sometimes. In a memory constrained environment like the kdump image, a softlockup is not just a harmless message, bu

  2. Oct 15, 2026 · NIST NVD

    Updated

    In the Linux kernel, the following vulnerability has been resolved: fs/proc: fix softlockup in __read_vmcore (part 2) Since commit 5cbcb62dddf5 ("fs/proc: fix softlockup in __read_vmcore") the number of softlockups in __read_vmcore at kdump time have gone down, but they still happen sometimes. In a memory constrained environment like the kdump image, a softlockup is not just a harmless message, bu

Affected

  • cpe linux/linux kernelversion unspecified
  • cpe linux/linux kernel6.13

Sources

  • CVE.orgVulnerability recordCVE-2025-21694

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2025-21694

    30-day exploitation probability 0.2%

    first.org
  • NIST NVDVulnerability recordCVE-2025-21694

    In the Linux kernel, the following vulnerability has been resolved: fs/proc: fix softlockup in __read_vmcore (part 2) Since commit 5cbcb62dddf5 ("fs/proc: fix softlockup in __read_vmcore") the number of softlockups in __read_vmcore at kdump time have gone down, but they still h

    nvd.nist.gov

References