Commit a3b2c8c7 authored May 31, 2013 by Mathias Krause Committed by Greg Kroah-Hartman Jun 03, 2013

debugfs: write_file_bool() - ensure strtobool() operates on valid data



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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 3a76e5e0

fs/debugfs/file.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -473,6 +473,7 @@ 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;