Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1160996AbXALFVB (ORCPT ); Fri, 12 Jan 2007 00:21:01 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1160997AbXALFVB (ORCPT ); Fri, 12 Jan 2007 00:21:01 -0500 Received: from smtp.osdl.org ([65.172.181.24]:33872 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1160996AbXALFVA (ORCPT ); Fri, 12 Jan 2007 00:21:00 -0500 Date: Thu, 11 Jan 2007 21:20:39 -0800 From: Andrew Morton To: "Serge E. Hallyn" Cc: lkml Subject: Re: [PATCH -mm 7/8] user_ns: handle file sigio Message-Id: <20070111212039.68e57e65.akpm@osdl.org> In-Reply-To: <20070104181257.GH11377@sergelap.austin.ibm.com> References: <20070104180635.GA11377@sergelap.austin.ibm.com> <20070104181257.GH11377@sergelap.austin.ibm.com> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3638 Lines: 70 On Thu, 4 Jan 2007 12:12:57 -0600 "Serge E. Hallyn" wrote: > A process in one user namespace could set a fowner and sigio on a file in a > shared vfsmount, ending up killing a task in another user namespace. > > Prevent this by adding a user namespace pointer to the fown_struct, and > enforcing that a process causing a signal to be sent be in the same > user namespace as the file owner. This patch breaks the X server (stock FC5 install) with CONFIG_USER_NS=n. Neither the USB mouse nor the trackpad work. They work OK under GPM. Setting CONFIG_USER_NS=y "fixes" this. This bug was not observed in 2.6.20-rc3-mm1 because that kernel had user-ns-always-on.patch for other reasons. (I'll restore that patch). There's nothing very interesting here: sony:/home/akpm> diff -u Xorg.0.log.good Xorg.0.log.bad --- Xorg.0.log.good 2007-01-11 21:11:11.000000000 -0800 +++ Xorg.0.log.bad 2007-01-11 21:17:31.000000000 -0800 @@ -6,7 +6,7 @@ Release Date: 21 December 2005 X Protocol Version 11, Revision 0, Release 7.0 Build Operating System:Linux 2.6.9-22.18.bz155725.ELsmp i686Red Hat, Inc. -Current Operating System: Linux sony 2.6.20-rc4-mm1 #15 Thu Jan 11 21:07:58 PST 2007 i686 +Current Operating System: Linux sony 2.6.20-rc4-mm1 #16 Thu Jan 11 21:14:03 PST 2007 i686 Build Date: 22 March 2006 Before reporting problems, check http://wiki.x.org to make sure that you have the latest version. @@ -14,7 +14,7 @@ Markers: (--) probed, (**) from config file, (==) default setting, (++) from command line, (!!) notice, (II) informational, (WW) warning, (EE) error, (NI) not implemented, (??) unknown. -(==) Log file: "/var/log/Xorg.0.log", Time: Thu Jan 11 21:10:16 2007 +(==) Log file: "/var/log/Xorg.0.log", Time: Thu Jan 11 21:16:39 2007 (==) Using config file: "/etc/X11/xorg.conf" (==) ServerLayout "single head configuration" (**) |-->Screen "Screen0" (0) @@ -2117,9 +2117,9 @@ (II) I810(0): Allocated 128 kB for the ring buffer at 0x0 (II) I810(0): Allocating at least 256 scanlines for pixmap cache (II) I810(0): Initial framebuffer allocation size: 12288 kByte -(II) I810(0): Allocated 4 kB for HW cursor at 0xffff000 (0x35dd3000) -(II) I810(0): Allocated 16 kB for HW (ARGB) cursor at 0xfffb000 (0x35e78000) -(II) I810(0): Allocated 4 kB for Overlay registers at 0xfffa000 (0x35e39000). +(II) I810(0): Allocated 4 kB for HW cursor at 0xffff000 (0x358d5000) +(II) I810(0): Allocated 16 kB for HW (ARGB) cursor at 0xfffb000 (0x35888000) +(II) I810(0): Allocated 4 kB for Overlay registers at 0xfffa000 (0x358d7000). (II) I810(0): Allocated 64 kB for the scratch buffer at 0xffea000 drmOpenDevice: node name is /dev/dri/card0 drmOpenDevice: open result is -1, (No such device or address) @@ -2137,8 +2137,8 @@ (II) I810(0): [drm] loaded kernel module for "i915" driver (II) I810(0): [drm] DRM interface version 1.3 (II) I810(0): [drm] created "i915" driver at busid "pci:0000:00:02.0" -(II) I810(0): [drm] added 8192 byte SAREA at 0xf8e46000 -(II) I810(0): [drm] mapped SAREA 0xf8e46000 to 0xb7eec000 +(II) I810(0): [drm] added 8192 byte SAREA at 0xf8d4a000 +(II) I810(0): [drm] mapped SAREA 0xf8d4a000 to 0xb7f23000 (II) I810(0): [drm] framebuffer handle = 0xc0020000 (II) I810(0): [drm] added 1 reserved context for kernel (II) I810(0): Allocated 32 kB for the logical context at 0xffe2000. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/