Messages in this thread | | | Date | Sun, 31 May 2009 11:24:40 +0100 | From | Alan Cox <> | Subject | Re: [patch 0/5] Support for sanitization flag in low-level page allocator |
| |
> On Sun, May 31, 2009 at 2:10 AM, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote: > > #2 Using kzfree() to clear specific bits of memory (and I question the > > kzfree implementation as it seems ksize can return numbers much much > > bigger than the allocated space you need to clear - correct but oversize) > > or using other flags. I'd favour kzfree personally (and fixing it to work > > properly) > > Well, yes, that's what kzfree() needs to do given the current API. I > am not sure why you think it's a problem, though. Adding a size > argument to the function will make it more error prone.
Definitely - am I right however that
x = kzalloc(size, flags) blah kzfree(x)
can memset a good deal more memory (still safely) than "size" to zero ? That has performance relevance if so and it ought to at least be documented.
> On Sun, May 31, 2009 at 2:10 AM, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote: > > #3 People wanting to be able to select for more security *irrespective* > > of performance cost. Which is no different to SELinux for example. > > Yeah, as I said before, I really don't have any objections to this. I > just think nobody is going to enable it so memset() or kzfree() in > relevant places is probably a good idea.
Agreed entirely.
| |