From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [PATCH] sys_waitid: return -EFAULT for NULL Date: Tue, 13 Jan 2009 15:24:57 -0800 Message-ID: <20090113152457.0d7685ad.akpm@linux-foundation.org> References: <20090113224759.7DFB7FC3DD@magilla.sf.frob.com> <20090113224941.36F19FC3DD@magilla.sf.frob.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-man-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Cc: mtk.manpages-gM/Ye1E23mwN+BqQ9rBEUg@public.gmane.org, roland-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, drepper-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, vegard.nossum-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, linux-man-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, stable-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org List-Id: linux-man@vger.kernel.org On Wed, 14 Jan 2009 12:14:20 +1300 "Michael Kerrisk" wrote: > On Wed, Jan 14, 2009 at 11:49 AM, Roland McGrath wrote: > > It's always been invalid to call waitid() with a NULL pointer. It was an > > oversight that it was allowed (and acts like a wait4() call instead). > > > > Signed-off-by: Roland McGrath > > Modulo the observation that this change will break any Linux-specific > application that violate POSIX.1's requirement that infop not be NULL > (*), and rely on the existing Linux behavior for > waitd(idtype,id,NULL,options): > Well yes. waitid() has been in there since 2.6.9. I assume that it has had this wait4-emulation mode for that amount of time as well? > > (*) It seems unlikely that such applications exist, and we really > should make this change for POSIX.1 conformance. Well, we might get away with it. But formally speaking, we should live with our Linux-specific screwup. If we _are_ going to make this change then we should merge it as far back in -stable as we can, to reduce the risk that people will develop applications on kernel version A only to have then behave differently on version B. -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html