Re: [PATCH] kmsg: Use vmalloc instead of kmalloc when writing

Greg KH
2012-03-30T15:30:24Z

On Fri, Mar 30, 2012 at 01:04:27PM -0400, Sasha Levin wrote:
> There are no size checks in kmsg_write(), and we try allocating enough
> memory to store everything userspace gave us, which may be too much for
> kmalloc to allocate.

Really? Have you seen this fail? As only root can do this, is this
really a problem?

> One option would be to limit it to something, but we can't come up with
> a number that would make sense.
>
> Instead, just use vmalloc so that nothing would break with large amounts
> of data.

Are you sure this will work properly? Have you tested it with large
amounts of data?

thanks,

greg k-h