I apologize for not mentioning that I ran this patch set
through orangefs xfstests at 5.7 rc5 with no problems
or regressions.
-Mike
On Sun, May 17, 2020 at 5:47 PM Guoqing Jiang
<guoqing.jiang@xxxxxxxxxxxxxxx> wrote:
>
> Since the new pair function is introduced, we can call them to clean the
> code in orangefs.
>
> Cc: Mike Marshall <hubcap@xxxxxxxxxxxx>
> Cc: Martin Brandenburg <martin@xxxxxxxxxxxx>
> Cc: devel@xxxxxxxxxxxxxxxxxx
> Signed-off-by: Guoqing Jiang <guoqing.jiang@xxxxxxxxxxxxxxx>
> ---
> No change since RFC V3.
>
> RFC V2 -> RFC V3
> 1. rename clear_page_private to detach_page_private.
>
> RFC -> RFC V2
> 1. change the name of new functions to attach/clear_page_private.
> 2. avoid potential use-after-free as suggested by Dave Chinner.
>
> fs/orangefs/inode.c | 32 ++++++--------------------------
> 1 file changed, 6 insertions(+), 26 deletions(-)
>
> diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c
> index 12ae630fbed7..48f0547d4850 100644
> --- a/fs/orangefs/inode.c
> +++ b/fs/orangefs/inode.c
> @@ -62,12 +62,7 @@ static int orangefs_writepage_locked(struct page *page,
> } else {
> ret = 0;
> }
> - if (wr) {
> - kfree(wr);
> - set_page_private(page, 0);
> - ClearPagePrivate(page);
> - put_page(page);
> - }
> + kfree(detach_page_private(page));
> return ret;
> }
>
> @@ -409,9 +404,7 @@ static int orangefs_write_begin(struct file *file,
> wr->len = len;
> wr->uid = current_fsuid();
> wr->gid = current_fsgid();
> - SetPagePrivate(page);
> - set_page_private(page, (unsigned long)wr);
> - get_page(page);
> + attach_page_private(page, wr);
> okay:
> return 0;
> }
> @@ -459,18 +452,12 @@ static void orangefs_invalidatepage(struct page *page,
> wr = (struct orangefs_write_range *)page_private(page);
>
> if (offset == 0 && length == PAGE_SIZE) {
> - kfree((struct orangefs_write_range *)page_private(page));
> - set_page_private(page, 0);
> - ClearPagePrivate(page);
> - put_page(page);
> + kfree(detach_page_private(page));
> return;
> /* write range entirely within invalidate range (or equal) */
> } else if (page_offset(page) + offset <= wr->pos &&
> wr->pos + wr->len <= page_offset(page) + offset + length) {
> - kfree((struct orangefs_write_range *)page_private(page));
> - set_page_private(page, 0);
> - ClearPagePrivate(page);
> - put_page(page);
> + kfree(detach_page_private(page));
> /* XXX is this right? only caller in fs */
> cancel_dirty_page(page);
> return;
> @@ -535,12 +522,7 @@ static int orangefs_releasepage(struct page *page, gfp_t foo)
>
> static void orangefs_freepage(struct page *page)
> {
> - if (PagePrivate(page)) {
> - kfree((struct orangefs_write_range *)page_private(page));
> - set_page_private(page, 0);
> - ClearPagePrivate(page);
> - put_page(page);
> - }
> + kfree(detach_page_private(page));
> }
>
> static int orangefs_launder_page(struct page *page)
> @@ -740,9 +722,7 @@ vm_fault_t orangefs_page_mkwrite(struct vm_fault *vmf)
> wr->len = PAGE_SIZE;
> wr->uid = current_fsuid();
> wr->gid = current_fsgid();
> - SetPagePrivate(page);
> - set_page_private(page, (unsigned long)wr);
> - get_page(page);
> + attach_page_private(page, wr);
> okay:
>
> file_update_time(vmf->vma->vm_file);
> --
> 2.17.1
>
