Re: Taking strlen of buffers copied from userspace

Robert Hancock
2005-03-16T05:25:02Z

Randy.Dunlap wrote:
> The latter one does (before the listed code):
>
> memset(line, 0, LINE_SIZE);
> if (len > LINE_SIZE)
> len = LINE_SIZE;
> if (copy_from_user(line, buf, len - 1))
> return -EFAULT;
>
> so isn't line[LINE_SIZE - 1] always 0 ?

In that case, yes (I hadn't looked at the surrounding code). Rather an
odd way of doing it, but shouldn't have that problem. Could still be
subject to problems if buf contains a null at the first character,
unless they're somehow preventing that too..

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