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CVE-2026-64162 Linux CVE debrief

A vulnerability was found in the Linux kernel. The idpf: fix read_dev_clk_lock spinlock init in idpf_ptp_init() vulnerability has been resolved. In idpf_ptp_init(), read_dev_clk_lock is initialized after ptp_schedule_worker() had already been called (and after idpf_ptp_settime64() could reach the lock). The PTP aux worker fires immediately upon scheduling and can call into idpf_ptp_read_src_clk_reg_direct(), which takes spin_lock(&ptp->read_dev_clk_lock) on an uninitialized lock, triggering the lockdep 'non-static key' warning. This vulnerability has been resolved by moving the call to spin_lock_init() up to ensure read_dev_clk_lock is initialized before it is touched.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-19
Original CVE updated
2026-07-19
Advisory published
2026-07-19
Advisory updated
2026-07-19

Who should care

Linux kernel users and administrators should be aware of this vulnerability and take recommended actions to mitigate potential risks. They should review and apply the provided patches, update their Linux kernel to the latest version, and monitor system logs for potential lockdep warnings. Additionally, they should assess their exposure to this vulnerability and prioritize remediation efforts accordingly.

Technical summary

The vulnerability is caused by the initialization of read_dev_clk_lock after ptp_schedule_worker() has been called. This can lead to a lockdep 'non-static key' warning when the PTP aux worker calls idpf_ptp_read_src_clk_reg_direct(). To fix this, the call to spin_lock_init() should be moved up to ensure read_dev_clk_lock is initialized before it is touched. The Linux kernel users should be aware of the potential risks associated with this vulnerability and take recommended actions to mitigate them.

Defensive priority

Medium

Recommended defensive actions

  • Update the Linux kernel to the latest version
  • Review and apply the provided patches
  • Monitor system logs for potential lockdep warnings
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The vulnerability has been resolved in the Linux kernel. The fix involves moving the call to spin_lock_init() up to ensure read_dev_clk_lock is initialized before it is touched. Users should update their Linux kernel to the latest version and review and apply the provided patches. The CVE record was published on 2026-07-19T16:17:58.213Z and has not been modified since then. The source item URL and NVD detail provide additional information about the vulnerability.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-19T16:17:58.213Z and has not been modified since then.