From mboxrd@z Thu Jan 1 00:00:00 1970 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 45323C35250 for ; Sun, 9 Feb 2020 12:57:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 168C020733 for ; Sun, 9 Feb 2020 12:57:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581253072; bh=wPyKkLPiLP1pWCjdQ/4gHvUWhP8jV3OaotH/Lg7bna4=; h=Subject:To:Cc:From:Date:List-ID:From; b=ol5tKLdkVcEoB21wpAleVAxak09QbI7KyGpEr0ZDgeyNkNvddWUWUKhMYp3Pvl05t PLEeydNTkZda3S7t9cs7P74dayU1fzd5sMWc5hmvXZdH6R6FF6ZWsmpYTL1x3lG7+E 3dNCwPSFxsWKPCKV5qtLm9LMIWvZIzh/KYv8Eavs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727682AbgBIM5v (ORCPT ); Sun, 9 Feb 2020 07:57:51 -0500 Received: from out5-smtp.messagingengine.com ([66.111.4.29]:56595 "EHLO out5-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727514AbgBIM5v (ORCPT ); Sun, 9 Feb 2020 07:57:51 -0500 Received: from compute6.internal (compute6.nyi.internal [10.202.2.46]) by mailout.nyi.internal (Postfix) with ESMTP id A691321AA4; Sun, 9 Feb 2020 07:57:50 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute6.internal (MEProxy); Sun, 09 Feb 2020 07:57:50 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:message-id:mime-version:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=mIwUpj G9VKSrexVopvPWjHy4Qzz9G77DbqTGOqaUvIw=; b=c6eBHuFuTR71snZt2r6ZkA ACpCR91Eq4dAdwCA2RkAOH5HD7NqOILMzdEikPx3XJ7N9rN3S66bHZTjxPERs2Y3 uPtg/8QzbtpKtQu8BRCzvK1h1OSz+ijpTSnEVmMEcdkOeZ7O5GMZRVcfBwCjcsLZ gREQ1fivyInWx86bcmp6poI1IG0RWeDgwCakR3rKd+dsSkD+ufZnddCirP+6rvls ARgnocFNpp7HppkX/lbNI/790fYal8sCwuXVsx4SAHaA+JzVOkJeA6AAsI7TdCmJ Kj7tgPVqIeMXXZx/KTjHTs3srwa66g9HmFiCt7IHSS6/1GIom9u7qCd5F7AXBtKw == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedugedrheelgddvfecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecunecujfgurhepuffvhfffkfggtgfgsehtkeertddttd flnecuhfhrohhmpeeoghhrvghgkhhhsehlihhnuhigfhhouhhnuggrthhiohhnrdhorhhg qeenucfkphepfeekrdelkedrfeejrddufeehnecuvehluhhsthgvrhfuihiivgepfeenuc frrghrrghmpehmrghilhhfrhhomhepghhrvghgsehkrhhorghhrdgtohhm X-ME-Proxy: Received: from localhost (unknown [38.98.37.135]) by mail.messagingengine.com (Postfix) with ESMTPA id 5F0453060272; Sun, 9 Feb 2020 07:57:48 -0500 (EST) Subject: FAILED: patch "[PATCH] NFS: Directory page cache pages need to be locked when read" failed to apply to 4.4-stable tree To: trondmy@gmail.com, Anna.Schumaker@Netapp.com, bcodding@redhat.com, trond.myklebust@hammerspace.com Cc: From: Date: Sun, 09 Feb 2020 12:24:35 +0100 Message-ID: <158124747522521@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 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 114de38225d9b300f027e2aec9afbb6e0def154b Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Sun, 2 Feb 2020 17:53:54 -0500 Subject: [PATCH] NFS: Directory page cache pages need to be locked when read When a NFS directory page cache page is removed from the page cache, its contents are freed through a call to nfs_readdir_clear_array(). To prevent the removal of the page cache entry until after we've finished reading it, we must take the page lock. Fixes: 11de3b11e08c ("NFS: Fix a memory leak in nfs_readdir") Cc: stable@vger.kernel.org # v2.6.37+ Signed-off-by: Trond Myklebust Reviewed-by: Benjamin Coddington Signed-off-by: Anna Schumaker diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 451c48cdb1c2..d95c2c94bd87 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -702,8 +702,6 @@ int nfs_readdir_filler(void *data, struct page* page) static void cache_page_release(nfs_readdir_descriptor_t *desc) { - if (!desc->page->mapping) - nfs_readdir_clear_array(desc->page); put_page(desc->page); desc->page = NULL; } @@ -717,19 +715,28 @@ struct page *get_cache_page(nfs_readdir_descriptor_t *desc) /* * Returns 0 if desc->dir_cookie was found on page desc->page_index + * and locks the page to prevent removal from the page cache. */ static -int find_cache_page(nfs_readdir_descriptor_t *desc) +int find_and_lock_cache_page(nfs_readdir_descriptor_t *desc) { int res; desc->page = get_cache_page(desc); if (IS_ERR(desc->page)) return PTR_ERR(desc->page); - - res = nfs_readdir_search_array(desc); + res = lock_page_killable(desc->page); if (res != 0) - cache_page_release(desc); + goto error; + res = -EAGAIN; + if (desc->page->mapping != NULL) { + res = nfs_readdir_search_array(desc); + if (res == 0) + return 0; + } + unlock_page(desc->page); +error: + cache_page_release(desc); return res; } @@ -744,7 +751,7 @@ int readdir_search_pagecache(nfs_readdir_descriptor_t *desc) desc->last_cookie = 0; } do { - res = find_cache_page(desc); + res = find_and_lock_cache_page(desc); } while (res == -EAGAIN); return res; } @@ -783,7 +790,6 @@ int nfs_do_filldir(nfs_readdir_descriptor_t *desc) desc->eof = true; kunmap(desc->page); - cache_page_release(desc); dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n", (unsigned long long)*desc->dir_cookie, res); return res; @@ -829,13 +835,13 @@ int uncached_readdir(nfs_readdir_descriptor_t *desc) status = nfs_do_filldir(desc); + out_release: + nfs_readdir_clear_array(desc->page); + cache_page_release(desc); out: dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __func__, status); return status; - out_release: - cache_page_release(desc); - goto out; } /* The file offset position represents the dirent entry number. A @@ -900,6 +906,8 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx) break; res = nfs_do_filldir(desc); + unlock_page(desc->page); + cache_page_release(desc); if (res < 0) break; } while (!desc->eof);