Commit 9997d5dd authored by Arnaldo Carvalho de Melo's avatar Arnaldo Carvalho de Melo
Browse files

perf trace: Use zfree() to reduce chances of use after free 



Do defensive programming by using zfree() to initialize freed pointers
to NULL, so that eventual use after free result in a NULL pointer deref
instead of more subtle behaviour.

Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 789eae7f

tools/perf/builtin-trace.c

+4 −4
Original line number Diff line number Diff line
@@ -2288,7 +2288,7 @@ static void syscall__exit(struct syscall *sc) 
	if (!sc)

		return;



	free(sc->arg_fmt);

	zfree(&sc->arg_fmt);

}



static int trace__sys_enter(struct trace *trace, struct evsel *evsel,
@@ -3124,7 +3124,7 @@ static void evlist__free_syscall_tp_fields(struct evlist *evlist) 
		if (!et || !evsel->tp_format || strcmp(evsel->tp_format->system, "syscalls"))

			continue;



		free(et->fmt);

		zfree(&et->fmt);

		free(et);

	}

}
@@ -4670,11 +4670,11 @@ static void trace__exit(struct trace *trace) 
	int i;



	strlist__delete(trace->ev_qualifier);

	free(trace->ev_qualifier_ids.entries);

	zfree(&trace->ev_qualifier_ids.entries);

	if (trace->syscalls.table) {

		for (i = 0; i <= trace->sctbl->syscalls.max_id; i++)

			syscall__exit(&trace->syscalls.table[i]);

		free(trace->syscalls.table);

		zfree(&trace->syscalls.table);

	}

	syscalltbl__delete(trace->sctbl);

	zfree(&trace->perfconfig_events);