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[for-next][PATCH 5/5] tracing: Dont use the address of the buffer array name in copy_from_user

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From: Wang Xiaoqiang <wangxq10@lzu.edu.cn>

With the following code snippet:

    ...
    char buf[64];
    ...
    if (copy_from_user(&buf, ubuf, cnt))
    ...

Even though the value of "&buf" equals "buf", but there is no need
to get the address of the "buf" again. Use "buf" instead of "&buf".

Link: http://lkml.kernel.org/r/20160418152329.18b72bea@debian

Signed-off-by: Wang Xiaoqiang <wangxq10@lzu.edu.cn>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/trace.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 5e3ad3481e4b..46028d47d252 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3664,7 +3664,7 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf,
 	if (cnt >= sizeof(buf))
 		return -EINVAL;
 
-	if (copy_from_user(&buf, ubuf, cnt))
+	if (copy_from_user(buf, ubuf, cnt))
 		return -EFAULT;
 
 	buf[cnt] = 0;
@@ -4537,7 +4537,7 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf,
 	if (cnt > MAX_TRACER_SIZE)
 		cnt = MAX_TRACER_SIZE;
 
-	if (copy_from_user(&buf, ubuf, cnt))
+	if (copy_from_user(buf, ubuf, cnt))
 		return -EFAULT;
 
 	buf[cnt] = 0;
@@ -5327,7 +5327,7 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
 	if (cnt >= sizeof(buf))
 		return -EINVAL;
 
-	if (copy_from_user(&buf, ubuf, cnt))
+	if (copy_from_user(buf, ubuf, cnt))
 		return -EFAULT;
 
 	buf[cnt] = 0;
-- 
2.8.0.rc3

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[for-next][PATCH 0/5] tracing: More updates for 4.7 Steven Rostedt <rostedt@goodmis.org> - 2016-04-27 18:40 +0200
  [for-next][PATCH 3/5] tracing: Add check for NULL event field when creating hist field Steven Rostedt <rostedt@goodmis.org> - 2016-04-27 18:40 +0200
  [for-next][PATCH 5/5] tracing: Dont use the address of the buffer array name in  copy_from_user Steven Rostedt <rostedt@goodmis.org> - 2016-04-27 18:40 +0200
  [for-next][PATCH 2/5] tracing: checking for NULL instead of IS_ERR() Steven Rostedt <rostedt@goodmis.org> - 2016-04-27 18:40 +0200
  [for-next][PATCH 4/5] tracing: Handle tracing_map_alloc_elts() error path correctly Steven Rostedt <rostedt@goodmis.org> - 2016-04-27 18:40 +0200
  [for-next][PATCH 1/5] tracing: Do not inherit event-fork option for instances Steven Rostedt <rostedt@goodmis.org> - 2016-04-27 18:40 +0200

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