CVE-2026-90066

Summary

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

samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify

ftrace_direct_multi_init() assigns kthread_run()'s return value to simple_tsk without an IS_ERR() check. When kthread_run() fails it returns ERR_PTR(-ENOMEM), but init still returns 0, so the module loads with simple_tsk holding an error pointer. On unload, ftrace_direct_multi_exit() then passes that ERR_PTR to kthread_stop(), leading to a null-pointer-dereference.

Check the return value of kthread_run() with IS_ERR(); on failure, unregister the ftrace direct call and propagate the error code.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxe1067a07cfbc5a36abad3752fafe4c79e06db1bb < 7a96b9f6d5ba23dbce66c8a4a242effd4c01a830affected
LinuxLinuxe1067a07cfbc5a36abad3752fafe4c79e06db1bb < 98b7b2a29ae87937aa02ab9391543ef8c602cd94affected
LinuxLinuxe1067a07cfbc5a36abad3752fafe4c79e06db1bb < 626614df9080d7052fbe24dc90b5434717ab7a9faffected
LinuxLinuxe1067a07cfbc5a36abad3752fafe4c79e06db1bb < cf839636911d8313f3ecd098329fd0b96499e4cfaffected
LinuxLinuxe1067a07cfbc5a36abad3752fafe4c79e06db1bb < 6727b7618f49401acf373fa3ec5712e2ec52e5cfaffected
LinuxLinux5.16affected
LinuxLinux0 < 5.16unaffected
LinuxLinux6.6.157 <= 6.6.*unaffected
LinuxLinux6.12.110 <= 6.12.*unaffected
LinuxLinux6.18.52 <= 6.18.*unaffected
LinuxLinux7.2.6 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References