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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 942F9C54EE9 for ; Thu, 8 Sep 2022 21:25:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229714AbiIHVZU (ORCPT ); Thu, 8 Sep 2022 17:25:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56158 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229658AbiIHVZR (ORCPT ); Thu, 8 Sep 2022 17:25:17 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6A35E9C217 for ; Thu, 8 Sep 2022 14:25:16 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 15704B822A3 for ; Thu, 8 Sep 2022 21:25:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6281AC433C1; Thu, 8 Sep 2022 21:25:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1662672313; bh=PIkwN801hWDtiC90RvyMfOz9A3fCD2G50BPGSmF8eQg=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=okDFr2aBiUNfcNhypfgsJPqPJRc9nV0bxDgmDYYW9Qq1xKz0E3Cdtw+0fuoUvNXfp 1bw0yYAMvKkCjwbT4rtH6y0a08ADcMA2a0vLuI6HQp0ApugBfRNTC7DBMl2lk3G1uO uQ0WEP6Ijb8e9ag0I8g5yXtTYnqQUQNBw9E012ewMBgkVWrNq7O4cyvsCe4VxaLVMp 4b44hugJ9nR04/F4un5dF75biEaeYm14zQKqgRob0fOE+o7TCFAOs8yBh687zQ5Z20 b81HJNV7HJ+/diwsA/ojgnGXhEj5dXbTaYbx22CDgxs3idho6lvxAYULiVo/gJCDv4 2UW190/hk89aQ== Message-ID: Date: Thu, 8 Sep 2022 23:25:08 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.2.1 Subject: Re: [PATCH] mm/slub: fix to return errno if kmalloc() fails Content-Language: en-US To: Muchun Song , Chao Yu Cc: Linux MM , Andrew Morton , linux-kernel@vger.kernel.org, jaegeuk@kernel.org, Chao Yu , stable@kernel.org, syzbot+81684812ea68216e08c5@syzkaller.appspotmail.com, David Rientjes , Hyeonggon Yoo <42.hyeyoo@gmail.com>, Christoph Lameter References: <20220830141009.150075-1-chao@kernel.org> From: "Vlastimil Babka (SUSE)" In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/31/22 05:09, Muchun Song wrote: > > >> On Aug 30, 2022, at 22:10, Chao Yu wrote: Please use scripts/get_maintainer.pl next time, I could have missed this. >> From: Chao Yu >> >> In create_unique_id(), kmalloc(, GFP_KERNEL) can fail due to >> out-of-memory, if it fails, return errno correctly rather than >> triggering panic via BUG_ON(); > > I tend to agree with you. A mount operation shouldn’t panic the > kernel. Hmm kmalloc(64) shouldn't normally due that due to the the underlying page allocation falling into the "too small to fail" category, wonder if syzkaller was doing anything special here? But yeah we should get rid of all BUG_ONs eventually, just not sure if stable@ is needed here. >> >> kernel BUG at mm/slub.c:5893! >> Internal error: Oops - BUG: 0 [#1] PREEMPT SMP >> >> Call trace: >> sysfs_slab_add+0x258/0x260 mm/slub.c:5973 >> __kmem_cache_create+0x60/0x118 mm/slub.c:4899 >> create_cache mm/slab_common.c:229 [inline] >> kmem_cache_create_usercopy+0x19c/0x31c mm/slab_common.c:335 >> kmem_cache_create+0x1c/0x28 mm/slab_common.c:390 >> f2fs_kmem_cache_create fs/f2fs/f2fs.h:2766 [inline] >> f2fs_init_xattr_caches+0x78/0xb4 fs/f2fs/xattr.c:808 >> f2fs_fill_super+0x1050/0x1e0c fs/f2fs/super.c:4149 >> mount_bdev+0x1b8/0x210 fs/super.c:1400 >> f2fs_mount+0x44/0x58 fs/f2fs/super.c:4512 >> legacy_get_tree+0x30/0x74 fs/fs_context.c:610 >> vfs_get_tree+0x40/0x140 fs/super.c:1530 >> do_new_mount+0x1dc/0x4e4 fs/namespace.c:3040 >> path_mount+0x358/0x914 fs/namespace.c:3370 >> do_mount fs/namespace.c:3383 [inline] >> __do_sys_mount fs/namespace.c:3591 [inline] >> __se_sys_mount fs/namespace.c:3568 [inline] >> __arm64_sys_mount+0x2f8/0x408 fs/namespace.c:3568 >> >> Cc: >> Reported-by: syzbot+81684812ea68216e08c5@syzkaller.appspotmail.com >> Signed-off-by: Chao Yu > > Reviewed-by: Muchun Song > > Thanks. > >