From: Li Zefan <lizf@cn.fujitsu.com>
Date: Tue, 22 Sep 2009 05:51:54 +0000 (+0800)
Subject: tracing: Fix off-by-one in trace_get_user()
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=3c235a337e205da0f614e456be72881483dcde6e;p=deliverable%2Flinux.git

tracing: Fix off-by-one in trace_get_user()

Leave the last slot for the tailing '\0'.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <4AB865FA.5080801@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index a35925d222ba..ae17453dc0f9 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -415,7 +415,7 @@ int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
 
 	/* read the non-space input */
 	while (cnt && !isspace(ch)) {
-		if (parser->idx < parser->size)
+		if (parser->idx < parser->size - 1)
 			parser->buffer[parser->idx++] = ch;
 		else {
 			ret = -EINVAL;