CVE-2025-21679: btrfs: add the missing error handling inside get_canonical_dev_path

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-01-31 · updated 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: btrfs: add the missing error handling inside get_canonical_dev_path Inside function get_canonical_dev_path(), we call d_path() to get the final device path. But d_path() can return error, and in that case the next strscpy() call will trigger an invalid memory access. Add back the missing error handling for d_path().

Affected products

Linux kernel: from 6.12.5 before 6.12.11; 6.13-rc1, 6.13-rc2, 6.13-rc3, 6.13-rc4, 6.13-rc5, 6.13-rc6 (+1) — fixed in 6.12.11

How to fix

Upgrade to a fixed version: Linux kernel 6.12.11. Check the vendor advisory for mitigations.

References

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