From: Jue Wang <juew@xxxxxxxxxx> commit 31657170deaf1d8d2f6a1955fbc6fa9d228be036 upstream. Anon THP tails were already supported, but memory-failure may need to use page_address_in_vma() on file THP tails, which its page->mapping check did not permit: fix it. hughd adds: no current usage is known to hit the issue, but this does fix a subtle trap in a general helper: best fixed in stable sooner than later. Link: https://lkml.kernel.org/r/a0d9b53-bf5d-8bab-ac5-759dc61819c1@xxxxxxxxxx Fixes: 800d8c63b2e9 ("shmem: add huge pages support") Signed-off-by: Jue Wang <juew@xxxxxxxxxx> Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx> Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Reviewed-by: Yang Shi <shy828301@xxxxxxxxx> Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Alistair Popple <apopple@xxxxxxxxxx> Cc: Jan Kara <jack@xxxxxxx> Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx> Cc: Minchan Kim <minchan@xxxxxxxxxx> Cc: Naoya Horiguchi <naoya.horiguchi@xxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Cc: Peter Xu <peterx@xxxxxxxxxx> Cc: Ralph Campbell <rcampbell@xxxxxxxxxx> Cc: Shakeel Butt <shakeelb@xxxxxxxxxx> Cc: Wang Yugui <wangyugui@xxxxxxxxxxxx> Cc: Zi Yan <ziy@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- mm/rmap.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/mm/rmap.c b/mm/rmap.c index 62cd108bb2bd..14f84f70c557 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -709,11 +709,11 @@ unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma) if (!vma->anon_vma || !page__anon_vma || vma->anon_vma->root != page__anon_vma->root) return -EFAULT; - } else if (page->mapping) { - if (!vma->vm_file || vma->vm_file->f_mapping != page->mapping) - return -EFAULT; - } else + } else if (!vma->vm_file) { + return -EFAULT; + } else if (vma->vm_file->f_mapping != compound_head(page)->mapping) { return -EFAULT; + } return vma_address(page, vma); } -- 2.30.2
