From patchwork Wed Jun 3 22:56:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 11586329 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C9BDC138C for ; Wed, 3 Jun 2020 22:56:24 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 96F50207F5 for ; Wed, 3 Jun 2020 22:56:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="kIFvMjkW" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 96F50207F5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D6E4C280002; Wed, 3 Jun 2020 18:56:23 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id CF75C8E0006; Wed, 3 Jun 2020 18:56:23 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BE6CD280002; Wed, 3 Jun 2020 18:56:23 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0089.hostedemail.com [216.40.44.89]) by kanga.kvack.org (Postfix) with ESMTP id A27668E0006 for ; Wed, 3 Jun 2020 18:56:23 -0400 (EDT) Received: from smtpin11.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 60355180AD806 for ; Wed, 3 Jun 2020 22:56:23 +0000 (UTC) X-FDA: 76889411046.11.space42_8f0582c6c352d Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin11.hostedemail.com (Postfix) with ESMTP id 29988180F8B86 for ; Wed, 3 Jun 2020 22:56:23 +0000 (UTC) X-Spam-Summary: 2,0,0,fa031a88c9020064,d41d8cd98f00b204,akpm@linux-foundation.org,,RULES_HIT:41:355:379:800:960:966:967:973:988:989:1260:1263:1345:1359:1381:1431:1437:1534:1543:1711:1730:1747:1777:1792:1801:2196:2199:2393:2525:2559:2563:2682:2685:2859:2902:2933:2937:2939:2942:2945:2947:2951:2954:3022:3138:3139:3140:3141:3142:3353:3865:3866:3867:3870:3871:3934:3936:3938:3941:3944:3947:3950:3953:3956:3959:4321:4385:4605:5007:6261:6653:7208:7576:7903:8599:8603:9025:9113:9121:9545:10004:10913:11026:11658:11914:12043:12048:12296:12297:12438:12517:12519:12555:12679:12740:12783:12895:12986:13221:13229:13846:14181:14721:14849:21080:21433:21451:21627:21939:21990:30004:30029:30054:30056,0,RBL:198.145.29.99:@linux-foundation.org:.lbl8.mailshell.net-62.2.0.100 64.100.201.201,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: space42_8f0582c6c352d X-Filterd-Recvd-Size: 4632 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf41.hostedemail.com (Postfix) with ESMTP for ; Wed, 3 Jun 2020 22:56:22 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (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 A1C3D20659; Wed, 3 Jun 2020 22:56:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591224982; bh=pS+74XtOjkGLqG4vWbNsDgwEmWMVRXuUVqx4h+piNPw=; h=Date:From:To:Subject:In-Reply-To:From; b=kIFvMjkWfXmnP1arIxLxBnYvSPpHlD9Oy9shdcFitSkhC3UBwp5bLPni3aiVSK76b r9a0TcExfEr2VQlfXg5vKGLYq+Nt+im6MI8rwg+lYtaWAC/7YF0efFZGjMtOgkFxMe AvOhptyAaaz/DojYWbrNiQ9IdGoCMKssyJx1IF/8= Date: Wed, 03 Jun 2020 15:56:21 -0700 From: Andrew Morton To: akpm@linux-foundation.org, cl@linux.com, hulkci@huawei.com, iamjoonsoo.kim@lge.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, penberg@kernel.org, rientjes@google.com, torvalds@linux-foundation.org, wanghai38@huawei.com Subject: [patch 001/131] mm/slub: fix a memory leak in sysfs_slab_add() Message-ID: <20200603225621.vOOi_y7_o%akpm@linux-foundation.org> In-Reply-To: <20200603155549.e041363450869eaae4c7f05b@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Queue-Id: 29988180F8B86 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam03 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Wang Hai Subject: mm/slub: fix a memory leak in sysfs_slab_add() syzkaller reports for memory leak when kobject_init_and_add() returns an error in the function sysfs_slab_add() [1] When this happened, the function kobject_put() is not called for the corresponding kobject, which potentially leads to memory leak. This patch fixes the issue by calling kobject_put() even if kobject_init_and_add() fails. [1] BUG: memory leak unreferenced object 0xffff8880a6d4be88 (size 8): comm "syz-executor.3", pid 946, jiffies 4295772514 (age 18.396s) hex dump (first 8 bytes): 70 69 64 5f 33 00 ff ff pid_3... backtrace: [<00000000a0980095>] kstrdup+0x35/0x70 mm/util.c:60 [<00000000ef0cff3f>] kstrdup_const+0x3d/0x50 mm/util.c:82 [<00000000e2461486>] kvasprintf_const+0x112/0x170 lib/kasprintf.c:48 [<000000005d749e93>] kobject_set_name_vargs+0x55/0x130 lib/kobject.c:289 [<0000000094e31519>] kobject_add_varg lib/kobject.c:384 [inline] [<0000000094e31519>] kobject_init_and_add+0xd8/0x170 lib/kobject.c:473 [<0000000060f13e32>] sysfs_slab_add+0x1d8/0x290 mm/slub.c:5811 [<00000000fe1d9a22>] __kmem_cache_create+0x50a/0x570 mm/slub.c:4384 [<000000006a71a1b4>] create_cache+0x113/0x1e0 mm/slab_common.c:407 [<0000000089491438>] kmem_cache_create_usercopy+0x1a1/0x260 mm/slab_common.c:505 [<000000008c992595>] kmem_cache_create+0xd/0x10 mm/slab_common.c:564 [<000000005320c4b6>] create_pid_cachep kernel/pid_namespace.c:54 [inline] [<000000005320c4b6>] create_pid_namespace kernel/pid_namespace.c:96 [inline] [<000000005320c4b6>] copy_pid_ns+0x77c/0x8f0 kernel/pid_namespace.c:148 [<00000000fc8e1a2b>] create_new_namespaces+0x26b/0xa30 kernel/nsproxy.c:95 [<0000000080f0c9a5>] unshare_nsproxy_namespaces+0xa7/0x1e0 kernel/nsproxy.c:229 [<0000000007e05aea>] ksys_unshare+0x3d2/0x770 kernel/fork.c:2969 [<00000000e04c8e4b>] __do_sys_unshare kernel/fork.c:3037 [inline] [<00000000e04c8e4b>] __se_sys_unshare kernel/fork.c:3035 [inline] [<00000000e04c8e4b>] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3035 [<000000005c4707c7>] do_syscall_64+0xa1/0x530 arch/x86/entry/common.c:295 Link: http://lkml.kernel.org/r/20200602115033.1054-1-wanghai38@huawei.com Fixes: 80da026a8e5d ("mm/slub: fix slab double-free in case of duplicate sysfs filename") Signed-off-by: Wang Hai Reported-by: Hulk Robot Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Signed-off-by: Andrew Morton --- mm/slub.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/mm/slub.c~mm-slub-fix-a-memory-leak-in-sysfs_slab_add +++ a/mm/slub.c @@ -5835,8 +5835,10 @@ static int sysfs_slab_add(struct kmem_ca s->kobj.kset = kset; err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, "%s", name); - if (err) + if (err) { + kobject_put(&s->kobj); goto out; + } err = sysfs_create_group(&s->kobj, &slab_attr_group); if (err)