[PATCH] rtla: Fix segfault on multiple SIGINTs

[Tomas Glozar]

Detach stop_trace() from SIGINT/SIGALRM on tool clean-up to prevent it
from crashing RTLA by accessing freed memory.

This prevents a crash when multiple SIGINTs are received.

Fixes: d6899e560366 ("rtla/timerlat_hist: Abort event processing on second 
signal")
Fixes: 80967b354a76 ("rtla/timerlat_top: Abort event processing on second 
signal")
Signed-off-by: Tomas Glozar <tglo...@redhat.com>
---
 tools/tracing/rtla/src/common.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/tools/tracing/rtla/src/common.c b/tools/tracing/rtla/src/common.c
index ceff76a62a30..51cdf86d60d0 100644
--- a/tools/tracing/rtla/src/common.c
+++ b/tools/tracing/rtla/src/common.c
@@ -39,6 +39,18 @@ static void set_signals(struct common_params *params)
        }
 }
 
+/*
+ * unset_signals - unsets the signals to stop the tool
+ */
+static void unset_signals(struct common_params *params)
+{
+       signal(SIGINT, SIG_DFL);
+       if (params->duration) {
+               alarm(0);
+               signal(SIGALRM, SIG_DFL);
+       }
+}
+
 /*
  * common_parse_options - parse common command line options
  *
@@ -284,7 +296,7 @@ int run_tool(struct tool_ops *ops, int argc, char *argv[])
 
        retval = ops->main(tool);
        if (retval)
-               goto out_trace;
+               goto out_signals;
 
        if (params->user_workload && !params->user.stopped_running) {
                params->user.should_run = 0;
@@ -306,6 +318,8 @@ int run_tool(struct tool_ops *ops, int argc, char *argv[])
        if (ops->analyze)
                ops->analyze(tool, stopped);
 
+out_signals:
+       unset_signals(params);
 out_trace:
        trace_events_destroy(&tool->record->trace, params->events);
        params->events = NULL;
-- 
2.53.0