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=-9.8 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,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 4969CC5518A for ; Wed, 22 Apr 2020 10:46:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 289E720780 for ; Wed, 22 Apr 2020 10:46:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587552371; bh=9pA80RXAeQaWY+lyLFsKyR/D7ioBH6TG8ZHD81mhMwU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=rhW7g3JNEOvwfuDjBeDjMruTutYxq/mRganpRN56BdpqhvtYMpTiFGmMlKLP4LHKt Oax7NN1bMHkxCf5io+vCjhtEc5VkqXbL87uLpeN0/D4mVO9FPnzmeLyzrWAiUTvlK2 HP1lAiy/FDnSScrcW5tpzPy0949oUYtvTupnkbKc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729825AbgDVKRY (ORCPT ); Wed, 22 Apr 2020 06:17:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:53530 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729822AbgDVKRX (ORCPT ); Wed, 22 Apr 2020 06:17:23 -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 5C8362076B; Wed, 22 Apr 2020 10:17:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587550642; bh=9pA80RXAeQaWY+lyLFsKyR/D7ioBH6TG8ZHD81mhMwU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kOHO3IqnH7F585Y+5mjTi+Zy/S6OIldge+sTD96eHmRkBaMML2dngZ7TmvR5dVaFm Am2ExXtESgcaUIR6zNflCdm2URzu2BsZQ0JcPn53ysTtmUKXdM2YgyKuvN6LX3Juyw olLPmPuXe7P89HJU3aTgHM+SJ90up48yvP6xFg9c= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ilya Dryomov , Jason Dillaman , Sasha Levin Subject: [PATCH 5.4 033/118] rbd: call rbd_dev_unprobe() after unwatching and flushing notifies Date: Wed, 22 Apr 2020 11:56:34 +0200 Message-Id: <20200422095037.317196101@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200422095031.522502705@linuxfoundation.org> References: <20200422095031.522502705@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Ilya Dryomov [ Upstream commit 952c48b0ed18919bff7528501e9a3fff8a24f8cd ] 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: Sasha Levin --- drivers/block/rbd.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index bab9c546ba334..274beda31c356 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -6933,9 +6933,10 @@ static int rbd_dev_header_name(struct rbd_device *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; @@ -6986,7 +6987,7 @@ static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth) ret = rbd_dev_header_info(rbd_dev); if (ret) - goto err_out_watch; + goto err_out_probe; /* * If this image is the one being mapped, we have pool name and @@ -7035,12 +7036,11 @@ static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth) return 0; err_out_probe: - rbd_dev_unprobe(rbd_dev); -err_out_watch: if (!depth) up_write(&rbd_dev->header_rwsem); if (!depth) rbd_unregister_watch(rbd_dev); + rbd_dev_unprobe(rbd_dev); err_out_format: rbd_dev->image_format = 0; kfree(rbd_dev->spec->image_id); -- 2.20.1