[PATCH 5.10 073/290] perf traceevent: Ensure read cmdlines are null terminated.

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

From: Ian Rogers <irogers@google.com>

commit 137a5258939aca56558f3a23eb229b9c4b293917 upstream.

Issue detected by address sanitizer.

Fixes: cd4ceb63438e9e28 ("perf util: Save pid-cmdline mapping into tracing header")
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <redacted>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <redacted>
Link: http://lore.kernel.org/lkml/20210226221431.1985458-1-irogers@google.com (local)
Signed-off-by: Arnaldo Carvalho de Melo <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 tools/perf/util/trace-event-read.c |    1 +
 1 file changed, 1 insertion(+)

--- a/tools/perf/util/trace-event-read.c
+++ b/tools/perf/util/trace-event-read.c

@@ -361,6 +361,7 @@ static int read_saved_cmdline(struct tep
 		pr_debug("error reading saved cmdlines\n");
 		goto out;
 	}
+	buf[ret] = '\0';
 
 	parse_saved_cmdline(pevent, buf, size);
 	ret = 0;