From patchwork Fri Oct 22 19:08:33 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12578915 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2240C433FE for ; Fri, 22 Oct 2021 19:09:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E0C93610D0 for ; Fri, 22 Oct 2021 19:09:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234190AbhJVTL7 (ORCPT ); Fri, 22 Oct 2021 15:11:59 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:29628 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234125AbhJVTLG (ORCPT ); Fri, 22 Oct 2021 15:11:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634929728; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=n1VZb0Xn4N6NISvttD2ZUsy8jQn+4P0ig2av100Y160=; b=cPIvBj4HvUifeZSqabg9Xd4Z2HpNm9N/MYoqef+f4wSvaAUVONrvweEkmhhRd124c3gfRc 8mdARncpAZEalI+reUq3a85RCbeYtBSF0DSqUPJR4vekbe0MtKq4mpCcLlelyhzqd/KWWB ls/eCfctMfSwyMBBtO59ic2AugjHUOY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-563-cvUP9piaPTO_Ct04vmPNag-1; Fri, 22 Oct 2021 15:08:42 -0400 X-MC-Unique: cvUP9piaPTO_Ct04vmPNag-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 414A4801FCE; Fri, 22 Oct 2021 19:08:40 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id DAD7E17CDB; Fri, 22 Oct 2021 19:08:33 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH v2 42/53] afs: Fix afs_write_end() to handle len > page size From: David Howells To: linux-cachefs@redhat.com Cc: Jeff Layton , Jeff Layton , Marc Dionne , Al Viro , Matthew Wilcox , linux-afs@lists.infradead.org, dhowells@redhat.com, Trond Myklebust , Anna Schumaker , Steve French , Dominique Martinet , Jeff Layton , Matthew Wilcox , Alexander Viro , Omar Sandoval , Linus Torvalds , linux-afs@lists.infradead.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, v9fs-developer@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Fri, 22 Oct 2021 20:08:33 +0100 Message-ID: <163492971302.1038219.3619344566416020631.stgit@warthog.procyon.org.uk> In-Reply-To: <163492911924.1038219.13107463173777870713.stgit@warthog.procyon.org.uk> References: <163492911924.1038219.13107463173777870713.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org It is possible for the len argument to afs_write_end() to overrun the end of the page (len is used to key the size of the page in afs_write_start() when compound pages become a regular thing). Fix afs_write_end() to correctly trim the write length so that it doesn't exceed the end of the page. Fixes: 3003bbd0697b ("afs: Use the netfs_write_begin() helper") Reported-by: Jeff Layton Signed-off-by: David Howells Acked-by: Jeff Layton cc: Marc Dionne cc: Al Viro cc: Matthew Wilcox cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/162367682522.460125.5652091227576721609.stgit@warthog.procyon.org.uk/ # v1 --- fs/afs/write.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/afs/write.c b/fs/afs/write.c index ced72c6b9a80..19be3153d610 100644 --- a/fs/afs/write.c +++ b/fs/afs/write.c @@ -119,6 +119,7 @@ int afs_write_end(struct file *file, struct address_space *mapping, _enter("{%llx:%llu},{%lx}", vnode->fid.vid, vnode->fid.vnode, page->index); + len = min_t(size_t, len, thp_size(page) - from); if (!PageUptodate(page)) { if (copied < len) { copied = 0;