aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/mm/hugetlb.c
diff options
context:
space:
mode:
authorZi Yan <ziy@nvidia.com>2023-09-13 16:12:45 -0400
committerAndrew Morton <akpm@linux-foundation.org>2023-10-04 10:32:29 -0700
commit426056efe835cf4864ccf4c328fe3af9146fc539 (patch)
tree7a36e306348817e84a9ab87c88a1b003e6f42ceb /mm/hugetlb.c
parentmm/cma: use nth_page() in place of direct struct page manipulation (diff)
downloadwireguard-linux-426056efe835cf4864ccf4c328fe3af9146fc539.tar.xz
wireguard-linux-426056efe835cf4864ccf4c328fe3af9146fc539.zip
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>
Diffstat (limited to 'mm/hugetlb.c')
-rw-r--r--mm/hugetlb.c2
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