tracing/kprobe: Fix a memory leak in error case

Fix a memory leak which happens when a field name conflicts with others. In
error case, free_trace_probe() will free all arguments until nr_args, so this
increments nr_args the begining of the loop instead of the end.

Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
LKML-Reference: <20100827113846.22882.12670.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

kernel/trace/trace_kprobe.c

@@ -992,6 +992,9 @@ static int create_trace_probe(int argc, char **argv)
 	/* parse arguments */
 	ret = 0;
 	for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
+		/* Increment count for freeing args in error case */
+		tp->nr_args++;
+
 		/* Parse argument name */
 		arg = strchr(argv[i], '=');
 		if (arg)
@@ -1021,11 +1024,8 @@ static int create_trace_probe(int argc, char **argv)
 		ret = parse_probe_arg(arg, tp, &tp->args[i], is_return);
 		if (ret) {
 			pr_info("Parse error at argument%d. (%d)\n", i, ret);
-			kfree(tp->args[i].name);
 			goto error;
 		}
-
-		tp->nr_args++;
 	}
 
 	ret = register_trace_probe(tp);