From patchwork Tue May 25 18:02:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Trond Myklebust X-Patchwork-Id: 12279815 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48A12C47084 for ; Tue, 25 May 2021 18:02:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2DC28613F1 for ; Tue, 25 May 2021 18:02:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232514AbhEYSEP (ORCPT ); Tue, 25 May 2021 14:04:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:37488 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232250AbhEYSEN (ORCPT ); Tue, 25 May 2021 14:04:13 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1E1E661400 for ; Tue, 25 May 2021 18:02:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1621965763; bh=0na1AlFE4jd/lqYuo0yx4bg5RtgbvVJ+BoYv9SezeAY=; h=From:To:Subject:Date:From; b=RfispvswovGG3jW4J0HTUmChr+FKn3mnxjBBaMlLXD+gE8I2zOVcrX0m+8F+hAFpB L5XpaG0NN+g3jER5RhDG7obx1V3KNsCAGjLrvNMFxSMWZXCf9DSte3t65EH15HQG3l I6ViaE5nYT0wR9yM320atZfzD+zrQVSX7dC5e3crrcFZwdl0lGiI1pwCO2b9pr3MR/ LQPH6iyO8l4WlS5A60HBsa6MgR84AzOd7msLb7q+UbSesb860kJcIRJG239J6QEPpE QpL7rzfCFOFoTxZTlW6xmiWhq2N2nF6wcIKlhHCl01qlaMx5cMlK3lEsbDNpp0TgDq 3tEQFwMsIcuAw== From: trondmy@kernel.org To: linux-nfs@vger.kernel.org Subject: [PATCH v2 1/3] NFS: Fix an Oopsable condition in __nfs_pageio_add_request() Date: Tue, 25 May 2021 14:02:39 -0400 Message-Id: <20210525180241.261090-1-trondmy@kernel.org> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org From: Trond Myklebust Ensure that nfs_pageio_error_cleanup() resets the mirror array contents, so that the structure reflects the fact that it is now empty. Also change the test in nfs_pageio_do_add_request() to be more robust by checking whether or not the list is empty rather than relying on the value of pg_count. Fixes: a7d42ddb3099 ("nfs: add mirroring support to pgio layer") Signed-off-by: Trond Myklebust --- fs/nfs/pagelist.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c index 6c20b28d9d7c..d35c84af44e0 100644 --- a/fs/nfs/pagelist.c +++ b/fs/nfs/pagelist.c @@ -1094,15 +1094,16 @@ nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc, struct nfs_page *prev = NULL; unsigned int size; - if (mirror->pg_count != 0) { - prev = nfs_list_entry(mirror->pg_list.prev); - } else { + if (list_empty(&mirror->pg_list)) { if (desc->pg_ops->pg_init) desc->pg_ops->pg_init(desc, req); if (desc->pg_error < 0) return 0; mirror->pg_base = req->wb_pgbase; - } + mirror->pg_count = 0; + mirror->pg_recoalesce = 0; + } else + prev = nfs_list_entry(mirror->pg_list.prev); if (desc->pg_maxretrans && req->wb_nio > desc->pg_maxretrans) { if (NFS_SERVER(desc->pg_inode)->flags & NFS_MOUNT_SOFTERR)