Commit 5528f913 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

mm: fix missing page table unmap for stack guard page failure case 



.. which didn't show up in my tests because it's a no-op on x86-64 and
most other architectures.  But we enter the function with the last-level
page table mapped, and should unmap it at exit.

Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 320b2b8d

mm/memory.c

+3 −1
Original line number Diff line number Diff line
@@ -2792,8 +2792,10 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma, 
	spinlock_t *ptl;

	pte_t entry;



	if (check_stack_guard_page(vma, address) < 0)

	if (check_stack_guard_page(vma, address) < 0) {

		pte_unmap(page_table);

		return VM_FAULT_SIGBUS;

	}



	if (!(flags & FAULT_FLAG_WRITE)) {

		entry = pte_mkspecial(pfn_pte(my_zero_pfn(address),