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 <npiggin@suse.de>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Nick Piggin 2007-07-20 00:31:45 -07:00 committed by Linus Torvalds
parent e228929bc2
commit 1833633803
3 changed files with 4 additions and 5 deletions

View file

@ -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;
}

View file

@ -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 "

View file

@ -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;