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=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 E3602C2D0A3 for ; Tue, 3 Nov 2020 21:05:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D14521534 for ; Tue, 3 Nov 2020 21:05:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604437527; bh=JWzxfpresqJOYZvRPnd/oNGVemC7vMtT3zNCqZzwwl4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=mq6Ec3vSxx/3P/ECJ8CQs0LzyLXV4w0hr2dhaOKvyL3W2g0VT7RMcqaDShZZTFi/b Tyl+jp7cRY3/3psvJ0jMBp1a6APgLHcwZYsxaZb1fP/x77PQ3O1BU/erB8WG9ZNpVO 0RlCDUrjV++JA6GuvSVzuQS3d6sN4yUs9aRDlc2k= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387799AbgKCVF0 (ORCPT ); Tue, 3 Nov 2020 16:05:26 -0500 Received: from mail.kernel.org ([198.145.29.99]:43858 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387735AbgKCVFW (ORCPT ); Tue, 3 Nov 2020 16:05:22 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 1806A206B5; Tue, 3 Nov 2020 21:05:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604437521; bh=JWzxfpresqJOYZvRPnd/oNGVemC7vMtT3zNCqZzwwl4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=C0I0WRonbwWI1C5wKefACejLbTRj+aWEGIVKHaYzDNnqfJpNTC/D8TYBliCdZj4W0 3QRv/tDOUgW4ugkLPhDvSlSgQmhmQHZLbRFyrMHlAGtKqXy7zOPDCrn/nYe7UP9Z4m kjjLZWWbcWE7JBCBImsbrAbmblEbeJt4ZIogDoJE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, KoWei Sung , Song Liu Subject: [PATCH 4.19 112/191] md/raid5: fix oops during stripe resizing Date: Tue, 3 Nov 2020 21:36:44 +0100 Message-Id: <20201103203243.946879005@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201103203232.656475008@linuxfoundation.org> References: <20201103203232.656475008@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Song Liu commit b44c018cdf748b96b676ba09fdbc5b34fc443ada upstream. KoWei reported crash during raid5 reshape: [ 1032.252932] Oops: 0002 [#1] SMP PTI [...] [ 1032.252943] RIP: 0010:memcpy_erms+0x6/0x10 [...] [ 1032.252947] RSP: 0018:ffffba1ac0c03b78 EFLAGS: 00010286 [ 1032.252949] RAX: 0000784ac0000000 RBX: ffff91bec3d09740 RCX: 0000000000001000 [ 1032.252951] RDX: 0000000000001000 RSI: ffff91be6781c000 RDI: 0000784ac0000000 [ 1032.252953] RBP: ffffba1ac0c03bd8 R08: 0000000000001000 R09: ffffba1ac0c03bf8 [ 1032.252954] R10: 0000000000000000 R11: 0000000000000000 R12: ffffba1ac0c03bf8 [ 1032.252955] R13: 0000000000001000 R14: 0000000000000000 R15: 0000000000000000 [ 1032.252958] FS: 0000000000000000(0000) GS:ffff91becf500000(0000) knlGS:0000000000000000 [ 1032.252959] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1032.252961] CR2: 0000784ac0000000 CR3: 000000031780a002 CR4: 00000000001606e0 [ 1032.252962] Call Trace: [ 1032.252969] ? async_memcpy+0x179/0x1000 [async_memcpy] [ 1032.252977] ? raid5_release_stripe+0x8e/0x110 [raid456] [ 1032.252982] handle_stripe_expansion+0x15a/0x1f0 [raid456] [ 1032.252988] handle_stripe+0x592/0x1270 [raid456] [ 1032.252993] handle_active_stripes.isra.0+0x3cb/0x5a0 [raid456] [ 1032.252999] raid5d+0x35c/0x550 [raid456] [ 1032.253002] ? schedule+0x42/0xb0 [ 1032.253006] ? schedule_timeout+0x10e/0x160 [ 1032.253011] md_thread+0x97/0x160 [ 1032.253015] ? wait_woken+0x80/0x80 [ 1032.253019] kthread+0x104/0x140 [ 1032.253022] ? md_start_sync+0x60/0x60 [ 1032.253024] ? kthread_park+0x90/0x90 [ 1032.253027] ret_from_fork+0x35/0x40 This is because cache_size_mutex was unlocked too early in resize_stripes, which races with grow_one_stripe() that grow_one_stripe() allocates a stripe with wrong pool_size. Fix this issue by unlocking cache_size_mutex after updating pool_size. Cc: # v4.4+ Reported-by: KoWei Sung Signed-off-by: Song Liu Signed-off-by: Greg Kroah-Hartman --- drivers/md/raid5.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -2417,8 +2417,6 @@ static int resize_stripes(struct r5conf } else err = -ENOMEM; - mutex_unlock(&conf->cache_size_mutex); - conf->slab_cache = sc; conf->active_name = 1-conf->active_name; @@ -2441,6 +2439,8 @@ static int resize_stripes(struct r5conf if (!err) conf->pool_size = newsize; + mutex_unlock(&conf->cache_size_mutex); + return err; }