Re: [RFC 01/11] add generic versions of debugfs file operations

From: Al Viro
Date: Sat Feb 23 2008 - 07:24:59 EST


On Tue, Feb 19, 2008 at 05:04:36AM +0100, Arnd Bergmann wrote:
> + char buf[3];
> + u32 *val = file->private_data;
> +
> + if (*val)
> + buf[0] = 'Y';
> + else
> + buf[0] = 'N';
> + buf[1] = '\n';
> + buf[2] = 0x00;
> + return simple_read_from_buffer(user_buf, count, ppos, buf, 2);

Ewww - caps, \n... BTW, \0 is pointless here - simple_read_from_buffer() will
not access it with these arguments)...

> +{
> + char buf[32];
> + int buf_size;
> + u32 *val = file->private_data;
> +
> + buf_size = min(count, (sizeof(buf)-1));
> + if (copy_from_user(buf, user_buf, buf_size))
> + return -EFAULT;
> +
> + switch (buf[0]) {
> + case 'y':
> + case 'Y':
> + case '1':
> + *val = 1;
> + break;
> + case 'n':
> + case 'N':
> + case '0':
> + *val = 0;
> + break;

Please, check the length; sloppy input grammar is a bad idea. Hell, at the
very least you want -EINVAL if input is not recognized...
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