From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:49010 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753668AbcKULlB (ORCPT ); Mon, 21 Nov 2016 06:41:01 -0500 Subject: Patch "fuse: fix fuse_write_end() if zero bytes were copied" has been added to the 4.8-stable tree To: mszeredi@redhat.com, gregkh@linuxfoundation.org, viro@zeniv.linux.org.uk Cc: , From: Date: Mon, 21 Nov 2016 12:41:00 +0100 Message-ID: <147972846084187@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled fuse: fix fuse_write_end() if zero bytes were copied to the 4.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: fuse-fix-fuse_write_end-if-zero-bytes-were-copied.patch and it can be found in the queue-4.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 59c3b76cc61d1d676f965c192cc7969aa5cb2744 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Thu, 18 Aug 2016 09:10:44 +0200 Subject: fuse: fix fuse_write_end() if zero bytes were copied From: Miklos Szeredi commit 59c3b76cc61d1d676f965c192cc7969aa5cb2744 upstream. If pos is at the beginning of a page and copied is zero then page is not zeroed but is marked uptodate. Fix by skipping everything except unlock/put of page if zero bytes were copied. Reported-by: Al Viro Fixes: 6b12c1b37e55 ("fuse: Implement write_begin/write_end callbacks") Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman --- fs/fuse/file.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -1985,6 +1985,10 @@ static int fuse_write_end(struct file *f { struct inode *inode = page->mapping->host; + /* Haven't copied anything? Skip zeroing, size extending, dirtying. */ + if (!copied) + goto unlock; + if (!PageUptodate(page)) { /* Zero any unwritten bytes at the end of the page */ size_t endoff = (pos + copied) & ~PAGE_MASK; @@ -1995,6 +1999,8 @@ static int fuse_write_end(struct file *f fuse_write_update_size(inode, pos + copied); set_page_dirty(page); + +unlock: unlock_page(page); put_page(page); Patches currently in stable-queue which might be from mszeredi@redhat.com are queue-4.8/fuse-fix-fuse_write_end-if-zero-bytes-were-copied.patch