Re: [x86/uaccess] 5b710f34e1: kernel BUG at mm/usercopy.c:75!

[Linus Torvalds]

On Wed, Aug 17, 2016 at 2:50 PM, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> On Wed, Aug 17, 2016 at 2:45 PM, Linus Torvalds
>>
>> Networking does, but seems to use __GFP_COMP, at least in the one case
>> I checked (skbuff).
>
> Was this allocation really through kmalloc?

The networking one I looked at, no. But they do __GFP_COMP.

The task struct allocation generally is (alloc_task_struct_node()),
but as Rik pointed out, SLOB doesn't actually necessarily do the slab
book-keeping for multi-page allocations.

               Linus