CVE-2026-93829

smb: client: fix races in cifsd thread creation

State
Published
Severity
Not scored
Published
Sep 24, 2026
Updated
Oct 30, 2026
Reserved
Sep 18, 2026

Read the record on cve.org

Description

In the Linux kernel, the following vulnerability has been resolved:

smb: client: fix races in cifsd thread creation

The cifsd demultiplex thread can run and access tcp_ses before the parent thread has finished populating tcp_ses, which the worker thread accesses locklessly.

Also, the kthread_run macro may start the thread before returning the thread pointer. Because the pointer is part of the structure that the thread can access, if the kernel is preempted after the thread is spawned, but before the thread pointer is populated and the thread attempts to exit, it will sleep, waiting for a SIGKILL signal.

Fix this by moving creation of the thread to after all of tcp_ses'es fields are populated, and spawning the thread last, using a split kthread_create/wake_up_process logic.

Scores

The record has no CVSS score.

Weaknesses

The record names no weakness.

Affected Products

ProductVersions
LinuxLinux
  • aaf737adb6937339494d5a7111f0433cd9676db8 to before 2376fb3348b4fa72a5158c8a63ff2489e1956541Affected
  • aaf737adb6937339494d5a7111f0433cd9676db8 to before cfa09f63e75cf440c9be97d1e73d509bfbb2c2c5Affected
  • aaf737adb6937339494d5a7111f0433cd9676db8 to before ee8f811cbac56ffb738b3a73671a9e75b0f56e99Affected
  • aaf737adb6937339494d5a7111f0433cd9676db8 to before 0eee1e6cddd1d9ce14da06e0238ca8d3362dec90Affected
  • aaf737adb6937339494d5a7111f0433cd9676db8 to before e8a5cf2ff5a13fefb228f2069e29dd7d8e37185dAffected
LinuxLinux
  • 2.6.22Affected
  • before 2.6.22Not affected
  • 6.1.191 through 6.1.*Not affected
  • 6.6.158 through 6.6.*Not affected
  • 6.12.111 through 6.12.*Not affected
  • 6.18.53 through 6.18.*Not affected
  • 7.2 and laterNot affected

References

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