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: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2023-04-12 09:50:08 -03:00
parent 789eae7f20
commit 9997d5dd17

View File

@ -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);