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 0C3B2C2D0A3 for ; Tue, 3 Nov 2020 20:46:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C734E223EA for ; Tue, 3 Nov 2020 20:46:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604436381; bh=GvYhnV1FHtvFNjREAgiYTGTSeLvsO5aoJbmCfj2vzwU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=0a4LAn8hwxkr4oTydzytlScdmiSXcV7swwd7BVZzh9umu2ZpoPESYCImW3mfR2z6S zHQiVf9iC7mBlw3qoYZ55frzKrHw2Ul4wQvOEJibfvyJ+1s9fjrBYdrGY2CKpjwc9j PI99wLOdJMYpED9BgYxQOr45p65DU49ROOxUM7ic= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731177AbgKCUqS (ORCPT ); Tue, 3 Nov 2020 15:46:18 -0500 Received: from mail.kernel.org ([198.145.29.99]:35452 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730575AbgKCUqQ (ORCPT ); Tue, 3 Nov 2020 15:46:16 -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 3B7DC223EA; Tue, 3 Nov 2020 20:46:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604436375; bh=GvYhnV1FHtvFNjREAgiYTGTSeLvsO5aoJbmCfj2vzwU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LvZPoRMKWNjI+cxCi67UE3E80Ru5JHQrqLjYCURLaiOudwaTSMynsuCZhEwC1dzcO dEiryahhCx9iGmgMnjRXTdALstmGWZ1O6DMFLXzqYoqOhaLfSU9c4IYOMTLt8dMOLR gxQuPiBzS13xPq243NywDjsytNXps3E/FtswD0mc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, KoWei Sung , Song Liu Subject: [PATCH 5.9 185/391] md/raid5: fix oops during stripe resizing Date: Tue, 3 Nov 2020 21:33:56 +0100 Message-Id: <20201103203359.368162448@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201103203348.153465465@linuxfoundation.org> References: <20201103203348.153465465@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 @@ -2429,8 +2429,6 @@ 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; @@ -2453,6 +2451,8 @@ static int resize_stripes(struct r5conf if (!err) conf->pool_size = newsize; + mutex_unlock(&conf->cache_size_mutex); + return err; }