diff options
| author | Samuel Moelius <sam.moelius@trailofbits.com> | 2026-06-28 13:10:22 +0000 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2026-07-28 07:18:50 -0400 |
| commit | 693dc27c5286cb0fd0d8cf18c3ee924b22154e92 (patch) | |
| tree | a149ea565928de5bf236ce5da557ed6ad3dc7966 /kernel | |
| parent | 73301fb81a17dbf198a5bf6cdaefa3611232b88e (diff) | |
tracing: Reject invalid preemptirq_delay_test CPU affinity
preemptirq_delay_test accepts cpu_affinity as a module parameter and,
when it is non-negative, writes that CPU directly into a temporary
cpumask from the worker thread. Values outside nr_cpu_ids can set a bit
outside the allocated cpumask before the test reports a normal affinity
error.
Validate the requested CPU in preemptirq_delay_run() before setting it
in the temporary cpumask. Invalid affinity requests are reported by
the test thread and skipped before cpumask_set_cpu() can touch an
out-of-range bit.
Link: https://patch.msgid.link/20260628131021.2208632.6a5c6c959813.preemptirq-delay-test-invalid-cpu-affinity@trailofbits.com
Assisted-by: Codex:gpt-5.5-cyber-preview
Signed-off-by: Samuel Moelius <sam.moelius@trailofbits.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/preemptirq_delay_test.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/kernel/trace/preemptirq_delay_test.c b/kernel/trace/preemptirq_delay_test.c index acb0c971a408..69e5238737ed 100644 --- a/kernel/trace/preemptirq_delay_test.c +++ b/kernel/trace/preemptirq_delay_test.c @@ -6,6 +6,7 @@ */ #include <linux/trace_clock.h> +#include <linux/cpumask.h> #include <linux/delay.h> #include <linux/interrupt.h> #include <linux/irq.h> @@ -123,6 +124,13 @@ static int preemptirq_delay_run(void *data) return -ENOMEM; if (cpu_affinity > -1) { + unsigned int cpu = cpu_affinity; + + if (cpu >= nr_cpu_ids || !cpu_possible(cpu)) { + pr_err("cpu_affinity:%d, invalid CPU\n", cpu_affinity); + goto out; + } + cpumask_clear(cpu_mask); cpumask_set_cpu(cpu_affinity, cpu_mask); if (set_cpus_allowed_ptr(current, cpu_mask)) @@ -132,6 +140,7 @@ static int preemptirq_delay_run(void *data) for (i = 0; i < s; i++) (testfuncs[i])(i); +out: complete(&done); set_current_state(TASK_INTERRUPTIBLE); |