tracing: fprobe-event: Sanitize wildcard for fprobe event name

commit ec879e1 upstream.

Fprobe event accepts wildcards for the target functions, but unless user
specifies its event name, it makes an event with the wildcards.

  /sys/kernel/tracing # echo 'f mutex*' >> dynamic_events
  /sys/kernel/tracing # cat dynamic_events
  f:fprobes/mutex*__entry mutex*
  /sys/kernel/tracing # ls events/fprobes/
  enable         filter         mutex*__entry

To fix this, replace the wildcard ('*') with an underscore.

Link: https://lore.kernel.org/all/175535345114.282990.12294108192847938710.stgit@devnote2/

Fixes: 334e551 ("tracing/probes: Add fprobe events for tracing function entry and exit.")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: mhiramat

kernel/trace/trace.h

@@ -2204,7 +2204,7 @@ static inline bool is_good_system_name(const char *name)
 static inline void sanitize_event_name(char *name)
 {
 	while (*name++ != '\0')
-		if (*name == ':' || *name == '.')
+		if (*name == ':' || *name == '.' || *name == '*')
 			*name = '_';
 }