diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index eb44418574f9..96265a717ca4 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3663,12 +3663,17 @@ static char *trace_iter_expand_format(struct trace_iterator *iter) } /* Returns true if the string is safe to dereference from an event */ -static bool trace_safe_str(struct trace_iterator *iter, const char *str) +static bool trace_safe_str(struct trace_iterator *iter, const char *str, + bool star, int len) { unsigned long addr = (unsigned long)str; struct trace_event *trace_event; struct trace_event_call *event; + /* Ignore strings with no length */ + if (star && !len) + return true; + /* OK if part of the event data */ if ((addr >= (unsigned long)iter->ent) && (addr < (unsigned long)iter->ent + iter->ent_size)) @@ -3854,7 +3859,7 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt, * instead. See samples/trace_events/trace-events-sample.h * for reference. */ - if (WARN_ONCE(!trace_safe_str(iter, str), + if (WARN_ONCE(!trace_safe_str(iter, str, star, len), "fmt: '%s' current_buffer: '%s'", fmt, show_buffer(&iter->seq))) { int ret;