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,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 5C1A1C55189 for ; Wed, 22 Apr 2020 10:23:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 355DE2076B for ; Wed, 22 Apr 2020 10:23:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587550989; bh=bPwKDTKpL2Y+JZMMa3GJB3P5LJcrgEhmvE86xCxhotQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xAEP41Kd+e3MHSWT+8za6oljkf/xBnU3gNixWes2eDRmgs9t/5/reIyPWuoRbTxvD BWvsH6VtGwtQXcp20m1Ri38PrIOKtE1NSr1ODBkAoGS4Gr5UFlKCyPOezrvIh8nCWk frRPSUHDvFcgHjhGpttuErDK+2Zt0j3L+TykQaNc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730279AbgDVKXG (ORCPT ); Wed, 22 Apr 2020 06:23:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:57940 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729605AbgDVKVc (ORCPT ); Wed, 22 Apr 2020 06:21:32 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0471D2084D; Wed, 22 Apr 2020 10:21:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587550891; bh=bPwKDTKpL2Y+JZMMa3GJB3P5LJcrgEhmvE86xCxhotQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=w3Wg9uN99Vnttf1PmjqG9EaNa8hYorZy60IUj85apuccv5CEMONq+xpJ+9QPOUr9F YWnAFNfWlqCpJAdLxHiMjgKafYkqyWkAKQJyIt+j+xtV6vTvu5EL5npKxY0u5cjqhL W6sRsVvEwbu71I1BqIhmAxQjk4vy4iL+Nd1y0uZA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ilya Dryomov , Jason Dillaman Subject: [PATCH 5.6 017/166] rbd: call rbd_dev_unprobe() after unwatching and flushing notifies Date: Wed, 22 Apr 2020 11:55:44 +0200 Message-Id: <20200422095050.245586777@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200422095047.669225321@linuxfoundation.org> References: <20200422095047.669225321@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ilya Dryomov commit 952c48b0ed18919bff7528501e9a3fff8a24f8cd upstream. rbd_dev_unprobe() is supposed to undo most of rbd_dev_image_probe(), including rbd_dev_header_info(), which means that rbd_dev_header_info() isn't supposed to be called after rbd_dev_unprobe(). However, rbd_dev_image_release() calls rbd_dev_unprobe() before rbd_unregister_watch(). This is racy because a header update notify can sneak in: "rbd unmap" thread ceph-watch-notify worker rbd_dev_image_release() rbd_dev_unprobe() free and zero out header rbd_watch_cb() rbd_dev_refresh() rbd_dev_header_info() read in header The same goes for "rbd map" because rbd_dev_image_probe() calls rbd_dev_unprobe() on errors. In both cases this results in a memory leak. Fixes: fd22aef8b47c ("rbd: move rbd_unregister_watch() call into rbd_dev_image_release()") Signed-off-by: Ilya Dryomov Reviewed-by: Jason Dillaman Signed-off-by: Greg Kroah-Hartman --- drivers/block/rbd.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -6955,9 +6955,10 @@ static void rbd_print_dne(struct rbd_dev static void rbd_dev_image_release(struct rbd_device *rbd_dev) { - rbd_dev_unprobe(rbd_dev); if (rbd_dev->opts) rbd_unregister_watch(rbd_dev); + + rbd_dev_unprobe(rbd_dev); rbd_dev->image_format = 0; kfree(rbd_dev->spec->image_id); rbd_dev->spec->image_id = NULL; @@ -7007,7 +7008,7 @@ static int rbd_dev_image_probe(struct rb if (ret) { if (ret == -ENOENT && !need_watch) rbd_print_dne(rbd_dev, false); - goto err_out_watch; + goto err_out_probe; } /* @@ -7052,12 +7053,11 @@ static int rbd_dev_image_probe(struct rb return 0; err_out_probe: - rbd_dev_unprobe(rbd_dev); -err_out_watch: if (!depth) up_write(&rbd_dev->header_rwsem); if (need_watch) rbd_unregister_watch(rbd_dev); + rbd_dev_unprobe(rbd_dev); err_out_format: rbd_dev->image_format = 0; kfree(rbd_dev->spec->image_id);