[PATCH] fix possible PAGE_CACHE_SHIFT overflows

[safe/jmp/linux-2.6] / fs / mpage.c

diff --git a/fs/mpage.c b/fs/mpage.c
index f1d2d02..e431cb3 100644 (file)
--- a/fs/mpage.c
+++ b/fs/mpage.c
@@ -184,7 +184,7 @@ do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages,
        if (page_has_buffers(page))
                goto confused;
 
-       block_in_file = page->index << (PAGE_CACHE_SHIFT - blkbits);
+       block_in_file = (sector_t)page->index << (PAGE_CACHE_SHIFT - blkbits);
        last_block = (i_size_read(inode) + blocksize - 1) >> blkbits;
 
        bh.b_page = page;
@@ -466,7 +466,7 @@ __mpage_writepage(struct bio *bio, struct page *page, get_block_t get_block,
         * The page has no buffers: map it to disk
         */
        BUG_ON(!PageUptodate(page));
-       block_in_file = page->index << (PAGE_CACHE_SHIFT - blkbits);
+       block_in_file = (sector_t)page->index << (PAGE_CACHE_SHIFT - blkbits);
        last_block = (i_size - 1) >> blkbits;
        map_bh.b_page = page;
        for (page_block = 0; page_block < blocks_per_page; ) {