Linus Torvalds writes: (Summary) On Thu, Dec 14, 2017 at 2:02 PM, Peter Zijlstra <peterz@infradead.org>
At least the old get_user_pages_fast() code used to check the USER bit:
At least the old get_user_pages_fast() code used to check the USER bit:
unsigned long need_pte_bits = _PAGE_PRESENT|_PAGE_USER;
if (write)
need_pte_bits |= _PAGE_RW;
but that may have been lost when we converted over to the generic code.
It shouldn't actually _matter_, since we'd need to change access_ok()
anyway (and gup had better check that!)
Linus