Commit 98398c32 authored Dec 18, 2013 by Jianguo Wu Committed by Linus Torvalds Dec 18, 2013

mm/hugetlb: check for pte NULL pointer in __page_check_address()

In __page_check_address(), if address's pud is not present,
huge_pte_offset() will return NULL, we should check the return value.

Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: qiuxishi <qiuxishi@huawei.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 7ac18156

mm/rmap.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -600,7 +600,11 @@ pte_t __page_check_address(struct page page, struct mm_struct *mm,
		spinlock_t *ptl;

		if (unlikely(PageHuge(page))) {
		/* when pud is not present, pte will be NULL */
		pte = huge_pte_offset(mm, address);
		if (!pte)
		return NULL;

		ptl = huge_pte_lockptr(page_hstate(page), mm, pte);
		goto check;
		}