[for-next][PATCH 3/4] rtla: Fix double free

From: Steven Rostedt
Date: Sun Jul 31 2022 - 17:10:00 EST


From: Andreas Schwab <schwab@xxxxxxx>

Avoid double free by making trace_instance_destroy indempotent. When
trace_instance_init fails, it calls trace_instance_destroy, but its only
caller osnoise_destroy_tool calls it again.

Link: https://lkml.kernel.org/r/mvmilnlkyzx.fsf_-_@xxxxxxx

Fixes: 0605bf009f18 ("rtla: Add osnoise tool")
Signed-off-by: Andreas Schwab <schwab@xxxxxxx>
Acked-by: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
tools/tracing/rtla/src/trace.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/tools/tracing/rtla/src/trace.c b/tools/tracing/rtla/src/trace.c
index 5784c9f9e570..e1ba6d9f4265 100644
--- a/tools/tracing/rtla/src/trace.c
+++ b/tools/tracing/rtla/src/trace.c
@@ -134,13 +134,18 @@ void trace_instance_destroy(struct trace_instance *trace)
if (trace->inst) {
disable_tracer(trace->inst);
destroy_instance(trace->inst);
+ trace->inst = NULL;
}

- if (trace->seq)
+ if (trace->seq) {
free(trace->seq);
+ trace->seq = NULL;
+ }

- if (trace->tep)
+ if (trace->tep) {
tep_free(trace->tep);
+ trace->tep = NULL;
+ }
}

/*
--
2.35.1