bpf: Fix a possible task gone issue with bpf_send_signal[_thread]() helpers

[platform/kernel/linux-rpi.git] / kernel / trace / bpf_trace.c

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index f47274d..c09792c 100644 (file)
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -833,6 +833,7 @@ static void do_bpf_send_signal(struct irq_work *entry)
 
        work = container_of(entry, struct send_signal_irq_work, irq_work);
        group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
+       put_task_struct(work->task);
 }
 
 static int bpf_send_signal_common(u32 sig, enum pid_type type)
@@ -867,7 +868,7 @@ static int bpf_send_signal_common(u32 sig, enum pid_type type)
                 * to the irq_work. The current task may change when queued
                 * irq works get executed.
                 */
-               work->task = current;
+               work->task = get_task_struct(current);
                work->sig = sig;
                work->type = type;
                irq_work_queue(&work->irq_work);