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 730E1C433EF for ; Wed, 22 Jun 2022 22:56:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1359510AbiFVW4E (ORCPT ); Wed, 22 Jun 2022 18:56:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49976 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238725AbiFVW4C (ORCPT ); Wed, 22 Jun 2022 18:56:02 -0400 Received: from out03.mta.xmission.com (out03.mta.xmission.com [166.70.13.233]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0E144CD3 for ; Wed, 22 Jun 2022 15:56:00 -0700 (PDT) Received: from in01.mta.xmission.com ([166.70.13.51]:60862) by out03.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1o49GR-00BAi3-O6; Wed, 22 Jun 2022 16:55:59 -0600 Received: from ip68-227-174-4.om.om.cox.net ([68.227.174.4]:57402 helo=email.froward.int.ebiederm.org.xmission.com) by in01.mta.xmission.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1o49GP-002YCq-FP; Wed, 22 Jun 2022 16:55:59 -0600 From: "Eric W. Biederman" To: Alexey Gladkov Cc: LKML , Linux Containers , Dmitry Vyukov , Catalin Marinas , syzkaller-bugs@googlegroups.com, syzbot+b4b0d1b35442afbf6fd2@syzkaller.appspotmail.com References: <8735fyhyvy.fsf@email.froward.int.ebiederm.org> <20220622200729.2639663-1-legion@kernel.org> Date: Wed, 22 Jun 2022 17:55:22 -0500 In-Reply-To: <20220622200729.2639663-1-legion@kernel.org> (Alexey Gladkov's message of "Wed, 22 Jun 2022 22:07:29 +0200") Message-ID: <87y1xob95x.fsf@email.froward.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-XM-SPF: eid=1o49GP-002YCq-FP;;;mid=<87y1xob95x.fsf@email.froward.int.ebiederm.org>;;;hst=in01.mta.xmission.com;;;ip=68.227.174.4;;;frm=ebiederm@xmission.com;;;spf=softfail X-XM-AID: U2FsdGVkX1/26elwTItBzsE3kqrhYEqvZh6qW4CuuxM= X-SA-Exim-Connect-IP: 68.227.174.4 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: Re: [PATCH] ipc: Free mq_sysctls if ipc namespace creation failed X-SA-Exim-Version: 4.2.1 (built Sat, 08 Feb 2020 21:53:50 +0000) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Alexey Gladkov writes: > The problem that Dmitry Vyukov pointed out is that if setup_ipc_sysctls fails, > mq_sysctls must be freed before return. Can we get a tested-by from syzbot? It would be nice to confirm that this bug is the one syzbot was seeing. Thank you, Eric > executing program > BUG: memory leak > unreferenced object 0xffff888112fc9200 (size 512): > comm "syz-executor237", pid 3648, jiffies 4294970469 (age 12.270s) > hex dump (first 32 bytes): > ef d3 60 85 ff ff ff ff 0c 9b d2 12 81 88 ff ff ..`............. > 04 00 00 00 a4 01 00 00 00 00 00 00 00 00 00 00 ................ > backtrace: > [] kmemdup+0x23/0x50 mm/util.c:129 > [] kmemdup include/linux/fortify-string.h:456 [inline] > [] setup_mq_sysctls+0x4b/0x1c0 ipc/mq_sysctl.c:89 > [] create_ipc_ns ipc/namespace.c:63 [inline] > [] copy_ipcs+0x292/0x390 ipc/namespace.c:91 > [] create_new_namespaces+0xdc/0x4f0 kernel/nsproxy.c:90 > [] unshare_nsproxy_namespaces+0x9b/0x120 kernel/nsproxy.c:226 > [] ksys_unshare+0x2fe/0x600 kernel/fork.c:3165 > [] __do_sys_unshare kernel/fork.c:3236 [inline] > [] __se_sys_unshare kernel/fork.c:3234 [inline] > [] __x64_sys_unshare+0x12/0x20 kernel/fork.c:3234 > [] do_syscall_x64 arch/x86/entry/common.c:50 [inline] > [] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 > [] entry_SYSCALL_64_after_hwframe+0x46/0xb0 > > BUG: memory leak > unreferenced object 0xffff888112fd5f00 (size 256): > comm "syz-executor237", pid 3648, jiffies 4294970469 (age 12.270s) > hex dump (first 32 bytes): > 00 92 fc 12 81 88 ff ff 00 00 00 00 01 00 00 00 ................ > 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace: > [] kmalloc include/linux/slab.h:605 [inline] > [] kzalloc include/linux/slab.h:733 [inline] > [] __register_sysctl_table+0x7b/0x7f0 fs/proc/proc_sysctl.c:1344 > [] setup_mq_sysctls+0x12a/0x1c0 ipc/mq_sysctl.c:112 > [] create_ipc_ns ipc/namespace.c:63 [inline] > [] copy_ipcs+0x292/0x390 ipc/namespace.c:91 > [] create_new_namespaces+0xdc/0x4f0 kernel/nsproxy.c:90 > [] unshare_nsproxy_namespaces+0x9b/0x120 kernel/nsproxy.c:226 > [] ksys_unshare+0x2fe/0x600 kernel/fork.c:3165 > [] __do_sys_unshare kernel/fork.c:3236 [inline] > [] __se_sys_unshare kernel/fork.c:3234 [inline] > [] __x64_sys_unshare+0x12/0x20 kernel/fork.c:3234 > [] do_syscall_x64 arch/x86/entry/common.c:50 [inline] > [] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 > [] entry_SYSCALL_64_after_hwframe+0x46/0xb0 > > BUG: memory leak > unreferenced object 0xffff888112fbba00 (size 256): > comm "syz-executor237", pid 3648, jiffies 4294970469 (age 12.270s) > hex dump (first 32 bytes): > 78 ba fb 12 81 88 ff ff 00 00 00 00 01 00 00 00 x............... > 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace: > [] kmalloc include/linux/slab.h:605 [inline] > [] kzalloc include/linux/slab.h:733 [inline] > [] new_dir fs/proc/proc_sysctl.c:978 [inline] > [] get_subdir fs/proc/proc_sysctl.c:1022 [inline] > [] __register_sysctl_table+0x5a9/0x7f0 fs/proc/proc_sysctl.c:1373 > [] setup_mq_sysctls+0x12a/0x1c0 ipc/mq_sysctl.c:112 > [] create_ipc_ns ipc/namespace.c:63 [inline] > [] copy_ipcs+0x292/0x390 ipc/namespace.c:91 > [] create_new_namespaces+0xdc/0x4f0 kernel/nsproxy.c:90 > [] unshare_nsproxy_namespaces+0x9b/0x120 kernel/nsproxy.c:226 > [] ksys_unshare+0x2fe/0x600 kernel/fork.c:3165 > [] __do_sys_unshare kernel/fork.c:3236 [inline] > [] __se_sys_unshare kernel/fork.c:3234 [inline] > [] __x64_sys_unshare+0x12/0x20 kernel/fork.c:3234 > [] do_syscall_x64 arch/x86/entry/common.c:50 [inline] > [] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 > [] entry_SYSCALL_64_after_hwframe+0x46/0xb0 > > BUG: memory leak > unreferenced object 0xffff888112fbb900 (size 256): > comm "syz-executor237", pid 3648, jiffies 4294970469 (age 12.270s) > hex dump (first 32 bytes): > 78 b9 fb 12 81 88 ff ff 00 00 00 00 01 00 00 00 x............... > 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace: > [] kmalloc include/linux/slab.h:605 [inline] > [] kzalloc include/linux/slab.h:733 [inline] > [] new_dir fs/proc/proc_sysctl.c:978 [inline] > [] get_subdir fs/proc/proc_sysctl.c:1022 [inline] > [] __register_sysctl_table+0x5a9/0x7f0 fs/proc/proc_sysctl.c:1373 > [] setup_mq_sysctls+0x12a/0x1c0 ipc/mq_sysctl.c:112 > [] create_ipc_ns ipc/namespace.c:63 [inline] > [] copy_ipcs+0x292/0x390 ipc/namespace.c:91 > [] create_new_namespaces+0xdc/0x4f0 kernel/nsproxy.c:90 > [] unshare_nsproxy_namespaces+0x9b/0x120 kernel/nsproxy.c:226 > [] ksys_unshare+0x2fe/0x600 kernel/fork.c:3165 > [] __do_sys_unshare kernel/fork.c:3236 [inline] > [] __se_sys_unshare kernel/fork.c:3234 [inline] > [] __x64_sys_unshare+0x12/0x20 kernel/fork.c:3234 > [] do_syscall_x64 arch/x86/entry/common.c:50 [inline] > [] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 > [] entry_SYSCALL_64_after_hwframe+0x46/0xb0 > > Reported-by: syzbot+b4b0d1b35442afbf6fd2@syzkaller.appspotmail.com > Signed-off-by: Alexey Gladkov > --- > ipc/namespace.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/ipc/namespace.c b/ipc/namespace.c > index 754f3237194a..e1fcaedba4fa 100644 > --- a/ipc/namespace.c > +++ b/ipc/namespace.c > @@ -64,7 +64,7 @@ static struct ipc_namespace *create_ipc_ns(struct user_namespace *user_ns, > goto fail_put; > > if (!setup_ipc_sysctls(ns)) > - goto fail_put; > + goto fail_mq; > > sem_init_ns(ns); > msg_init_ns(ns); > @@ -72,6 +72,9 @@ static struct ipc_namespace *create_ipc_ns(struct user_namespace *user_ns, > > return ns; > > +fail_mq: > + retire_mq_sysctls(ns); > + > fail_put: > put_user_ns(ns->user_ns); > ns_free_inum(&ns->ns);