[merged mm-stable] mm-hugetlb-use-nth_page-in-place-of-direct-struct-page-manipulation.patch removed from -mm tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



The quilt patch titled
     Subject: mm/hugetlb: use nth_page() in place of direct struct page manipulation
has been removed from the -mm tree.  Its filename was
     mm-hugetlb-use-nth_page-in-place-of-direct-struct-page-manipulation.patch

This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Zi Yan <ziy@xxxxxxxxxx>
Subject: mm/hugetlb: use nth_page() in place of direct struct page manipulation
Date: Wed, 13 Sep 2023 16:12:45 -0400

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@xxxxxxxx
Fixes: 57a196a58421 ("hugetlb: simplify hugetlb handling in follow_page_mask")
Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 mm/hugetlb.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/hugetlb.c~mm-hugetlb-use-nth_page-in-place-of-direct-struct-page-manipulation
+++ a/mm/hugetlb.c
@@ -6493,7 +6493,7 @@ struct page *hugetlb_follow_page_mask(st
 			}
 		}
 
-		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
_

Patches currently in -mm which might be from ziy@xxxxxxxxxx are





[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux