From patchwork Wed Jun 8 19:19:10 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oleg Nesterov X-Patchwork-Id: 99542 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from ozlabs.org (localhost [IPv6:::1]) by ozlabs.org (Postfix) with ESMTP id 7A175B74C3 for ; Thu, 9 Jun 2011 05:22:15 +1000 (EST) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by ozlabs.org (Postfix) with ESMTP id BFE84B6FDA for ; Thu, 9 Jun 2011 05:22:01 +1000 (EST) Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p58JKnLT020232 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 8 Jun 2011 15:20:50 -0400 Received: from tranklukator.englab.brq.redhat.com (dhcp-1-166.brq.redhat.com [10.34.1.166]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with SMTP id p58JKfox006474; Wed, 8 Jun 2011 15:20:41 -0400 Received: by tranklukator.englab.brq.redhat.com (nbSMTP-1.00) for uid 500 oleg@redhat.com; Wed, 8 Jun 2011 21:19:18 +0200 (CEST) Date: Wed, 8 Jun 2011 21:19:10 +0200 From: Oleg Nesterov To: Eric Paris Subject: Re: [PATCH -v2] Audit: push audit success and retcode into arch ptrace.h Message-ID: <20110608191910.GA18698@redhat.com> References: <20110603220451.23134.47368.stgit@paris.rdu.redhat.com> <20110607171952.GA25729@redhat.com> <1307472796.2052.12.camel@localhost.localdomain> <20110608163653.GA9592@redhat.com> <1307556823.2577.5.camel@localhost.localdomain> <20110608183720.GA16883@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20110608183720.GA16883@redhat.com> User-Agent: Mutt/1.5.18 (2008-05-17) X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 Cc: linux-mips@linux-mips.org, linux-ia64@vger.kernel.org, linux-sh@vger.kernel.org, heiko.carstens@de.ibm.com, paulus@samba.org, hpa@zytor.com, sparclinux@vger.kernel.org, linux-s390@vger.kernel.org, richard@nod.at, x86@kernel.org, mingo@redhat.com, fenghua.yu@intel.com, user-mode-linux-devel@lists.sourceforge.net, microblaze-uclinux@itee.uq.edu.au, jdike@addtoit.com, viro@zeniv.linux.org.uk, tglx@linutronix.de, monstr@monstr.eu, tony.luck@intel.com, linux-kernel@vger.kernel.org, ralf@linux-mips.org, lethal@linux-sh.org, schwidefsky@de.ibm.com, linux390@de.ibm.com, akpm@linux-foundation.org, linuxppc-dev@lists.ozlabs.org, davem@davemloft.net X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org On 06/08, Oleg Nesterov wrote: > > OK. Thanks a lot Eric for your explanations. Yes. but may I ask another one? Shouldn't copy_process()->audit_alloc(tsk) path do clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT) if it doesn't set tsk->audit_context? I can be easily wrong, but afaics otherwise the child can run with TIF_SYSCALL_AUDIT bit copied from parent's thread_info by dup_task_struct()->setup_thread_stack() and without ->audit_context, right? For what? Any other reason why audit_syscall_entry() checks context != NULL? IOW. Any reason the patch below is wrong? I am just curious, thanks. Oleg. --- x/kernel/auditsc.c +++ x/kernel/auditsc.c @@ -885,6 +885,8 @@ int audit_alloc(struct task_struct *tsk) if (likely(!audit_ever_enabled)) return 0; /* Return if not auditing. */ + clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); + state = audit_filter_task(tsk, &key); if (likely(state == AUDIT_DISABLED)) return 0; @@ -1591,9 +1593,7 @@ void audit_syscall_entry(int arch, int m struct audit_context *context = tsk->audit_context; enum audit_state state; - if (unlikely(!context)) - return; - + BUG_ON(!context); /* * This happens only on certain architectures that make system * calls in kernel_thread via the entry.S interface, instead of