diff options
| author | Zi Yan <ziy@nvidia.com> | 2023-09-13 16:12:45 -0400 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-10-04 10:32:29 -0700 |
| commit | 426056efe835cf4864ccf4c328fe3af9146fc539 (patch) | |
| tree | 7a36e306348817e84a9ab87c88a1b003e6f42ceb | |
| parent | 2e7cfe5cd5b6b0b98abf57a3074885979e187c1c (diff) | |
mm/hugetlb: use nth_page() in place of direct struct page manipulation
When dealing with hugetlb pages, manipulating struct page pointers
directly can get to wrong struct page, since struct page is not guaranteed
to be contiguous on SPARSEMEM without VMEMMAP. Use nth_page() to handle
it properly.
A wrong or non-existing page might be tried to be grabbed, either
leading to a non freeable page or kernel memory access errors. No bug
is reported. It comes from code inspection.
Link: https://lkml.kernel.org/r/20230913201248.452081-3-zi.yan@sent.com
Fixes: 57a196a58421 ("hugetlb: simplify hugetlb handling in follow_page_mask")
Signed-off-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | mm/hugetlb.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 7c90c43574a6..a945efe2858a 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -6493,7 +6493,7 @@ struct page *hugetlb_follow_page_mask(struct vm_area_struct *vma, } } - page += ((address & ~huge_page_mask(h)) >> PAGE_SHIFT); + page = nth_page(page, ((address & ~huge_page_mask(h)) >> PAGE_SHIFT)); /* * Note that page may be a sub-page, and with vmemmap |