lkml.org 
[lkml]   [2013]   [May]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] debugfs: write_file_bool() - ensure strtobool() operates on valid data
Date
In case, userland writes an empty string to a bool debugfs file, buf[]
will still be uninitialized when being passed to strtobool() making the
outcome of that function purely random.

Fix this by always zero-terminating the buffer.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
---
fs/debugfs/file.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
index c5ca6ae..b15a1c5 100644
--- a/fs/debugfs/file.c
+++ b/fs/debugfs/file.c
@@ -431,6 +431,7 @@ static ssize_t write_file_bool(struct file *file, const char __user *user_buf,
if (copy_from_user(buf, user_buf, buf_size))
return -EFAULT;

+ buf[buf_size] = '\0';
if (strtobool(buf, &bv) == 0)
*val = bv;

--
1.7.10.4


\
 
 \ /
  Last update: 2013-06-01 00:01    [W:0.030 / U:0.492 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site