From 1833633803c7ef4d8f09877d3f1549cbd252f477 Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Fri, 20 Jul 2007 00:31:45 -0700 Subject: [PATCH] fix some conversion overflows Fix page index to offset conversion overflows in buffer layer, ecryptfs, and ocfs2. It would be nice to convert the whole tree to page_offset, but for now just fix the bugs. Signed-off-by: Nick Piggin Cc: Michael Halcrow Cc: Mark Fasheh Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/buffer.c | 2 +- fs/ecryptfs/mmap.c | 5 ++--- fs/ocfs2/mmap.c | 2 +- 3 files changed, 4 insertions(+), 5 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index 02ebb1f1d3..0e5ec371ce 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -2221,7 +2221,7 @@ block_page_mkwrite(struct vm_area_struct *vma, struct page *page, lock_page(page); size = i_size_read(inode); if ((page->mapping != inode->i_mapping) || - ((page->index << PAGE_CACHE_SHIFT) > size)) { + (page_offset(page) > size)) { /* page got truncated out from underneath us */ goto out_unlock; } diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c index 7d5a43cb0d..e4ab7bc14e 100644 --- a/fs/ecryptfs/mmap.c +++ b/fs/ecryptfs/mmap.c @@ -409,8 +409,7 @@ static int ecryptfs_prepare_write(struct file *file, struct page *page, if (!PageUptodate(page)) rc = ecryptfs_do_readpage(file, page, page->index); if (page->index != 0) { - loff_t end_of_prev_pg_pos = - (((loff_t)page->index << PAGE_CACHE_SHIFT) - 1); + loff_t end_of_prev_pg_pos = page_offset(page) - 1; if (end_of_prev_pg_pos > i_size_read(page->mapping->host)) { rc = ecryptfs_truncate(file->f_path.dentry, @@ -736,7 +735,7 @@ static int ecryptfs_commit_write(struct file *file, struct page *page, goto out; } inode->i_blocks = lower_inode->i_blocks; - pos = (page->index << PAGE_CACHE_SHIFT) + to; + pos = page_offset(page) + to; if (pos > i_size_read(inode)) { i_size_write(inode, pos); ecryptfs_printk(KERN_DEBUG, "Expanded file size to " diff --git a/fs/ocfs2/mmap.c b/fs/ocfs2/mmap.c index ee64749e2e..98756156d2 100644 --- a/fs/ocfs2/mmap.c +++ b/fs/ocfs2/mmap.c @@ -89,7 +89,7 @@ static int __ocfs2_page_mkwrite(struct inode *inode, struct buffer_head *di_bh, { int ret; struct address_space *mapping = inode->i_mapping; - loff_t pos = page->index << PAGE_CACHE_SHIFT; + loff_t pos = page_offset(page); unsigned int len = PAGE_CACHE_SIZE; pgoff_t last_index; struct page *locked_page = NULL; -- 2.39.5