tracing/probe: Fix same probe event argument matching

Commit fe60b0c ("tracing/probe: Reject exactly same probe event")
tries to reject a event which matches an already existing probe.

However it currently continues to match arguments and rejects adding a
probe even when the arguments don't match. Fix this by only rejecting a
probe if and only if all the arguments match.

Link: http://lkml.kernel.org/r/20190924114906.14038-1-srikar@linux.vnet.ibm.com

Fixes: fe60b0c ("tracing/probe: Reject exactly same probe event")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

kernel/trace/trace_kprobe.c

@@ -549,10 +549,11 @@ static bool trace_kprobe_has_same_kprobe(struct trace_kprobe *orig,
 		for (i = 0; i < orig->tp.nr_args; i++) {
 			if (strcmp(orig->tp.args[i].comm,
 				   comp->tp.args[i].comm))
-				continue;
+				break;
 		}
 
-		return true;
+		if (i == orig->tp.nr_args)
+			return true;
 	}
 
 	return false;

kernel/trace/trace_uprobe.c

@@ -431,10 +431,11 @@ static bool trace_uprobe_has_same_uprobe(struct trace_uprobe *orig,
 		for (i = 0; i < orig->tp.nr_args; i++) {
 			if (strcmp(orig->tp.args[i].comm,
 				   comp->tp.args[i].comm))
-				continue;
+				break;
 		}
 
-		return true;
+		if (i == orig->tp.nr_args)
+			return true;
 	}
 
 	return false;