CVE-2026-64163: test_kprobes: clear kprobes between test runs

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-19 · updated 2026-10-30

Description

In the Linux kernel, the following vulnerability has been resolved: test_kprobes: clear kprobes between test runs Running the kprobes sanity tests twice makes all tests fail and eventually crashes the kernel. [root@martin-riscv-1 ~]# echo 1 > /sys/kernel/debug/kunit/kprobes_test/run ... # Totals: pass:5 fail:0 skip:0 total:5 ok 1 kprobes_test [root@martin-riscv-1 ~]# echo 1 > /sys/kernel/debug/kunit/kprobes_test/run ... # test_kprobe: EXPECTATION FAILED at lib/tests/test_kprobes.c:64 Expected 0 == register_kprobe(&kp), but register_kprobe(&kp) == -22 (0xffffffffffffffea) ... Unable to handle kernel paging request ... The testsuite defines several kprobes and kretprobes as static variables that are preserved across test runs. After register_kprobe and unregister_kprobe, a kprobe contains some leftover data that must be cleared before the kprobe can be registered again. The tests are setting symbol_name to define the probe location. Address and flags must be cleared. The existing code clears some of the probes between subsequent tests, but not between two test runs. The leftover data from a previous test run makes the registrations fail in the next run. Move the cleanups for all kprobes into kprobes_test_init, this function is called before each single test (including the first test of a test run).

Affected products

Linux kernel: from 5.16 before 6.6.142; from 6.7 before 6.12.92; from 6.13 before 6.18.34; from 6.19 before 7.0.11; 7.1-rc1, 7.1-rc2, 7.1-rc3 — fixed in 6.6.142, 6.12.92, 6.18.34, 7.0.11
Linux: 5.16 — fixed in 7.1

How to fix

Upgrade to a fixed version: Linux kernel 6.6.142, 6.12.92, 6.18.34, 7.0.11; Linux 7.1. Check the vendor advisory for mitigations.

References

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