Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759472AbZDWHuJ (ORCPT ); Thu, 23 Apr 2009 03:50:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757218AbZDWHdQ (ORCPT ); Thu, 23 Apr 2009 03:33:16 -0400 Received: from sous-sol.org ([216.99.217.87]:50868 "EHLO x200.localdomain" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757142AbZDWHdP (ORCPT ); Thu, 23 Apr 2009 03:33:15 -0400 Message-Id: <20090423072746.113789813@sous-sol.org> User-Agent: quilt/0.47-1 Date: Thu, 23 Apr 2009 00:21:24 -0700 From: Chris Wright To: linux-kernel@vger.kernel.org, stable@kernel.org, jejb@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, "Serge E. Hallyn" , "J. Bruce Fields" Subject: [patch 064/100] add some long-missing capabilities to fs_mask References: <20090423072020.428683652@sous-sol.org> Content-Disposition: inline; filename=add-some-long-missing-capabilities-to-fs_mask.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3176 Lines: 83 -stable review patch. If anyone has any objections, please let us know. --------------------- From: Serge E. Hallyn upstream commit: 0ad30b8fd5fe798aae80df6344b415d8309342cc When POSIX capabilities were introduced during the 2.1 Linux cycle, the fs mask, which represents the capabilities which having fsuid==0 is supposed to grant, did not include CAP_MKNOD and CAP_LINUX_IMMUTABLE. However, before capabilities the privilege to call these did in fact depend upon fsuid==0. This patch introduces those capabilities into the fsmask, restoring the old behavior. See the thread starting at http://lkml.org/lkml/2009/3/11/157 for reference. Note that if this fix is deemed valid, then earlier kernel versions (2.4 and 2.2) ought to be fixed too. Changelog: [Mar 23] Actually delete old CAP_FS_SET definition... [Mar 20] Updated against J. Bruce Fields's patch Reported-by: Igor Zhbanov Signed-off-by: Serge E. Hallyn Cc: stable@kernel.org Cc: J. Bruce Fields Signed-off-by: Linus Torvalds Signed-off-by: Chris Wright --- include/linux/capability.h | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) --- a/include/linux/capability.h +++ b/include/linux/capability.h @@ -377,7 +377,21 @@ struct cpu_vfs_cap_data { #define CAP_FOR_EACH_U32(__capi) \ for (__capi = 0; __capi < _KERNEL_CAPABILITY_U32S; ++__capi) +/* + * CAP_FS_MASK and CAP_NFSD_MASKS: + * + * The fs mask is all the privileges that fsuid==0 historically meant. + * At one time in the past, that included CAP_MKNOD and CAP_LINUX_IMMUTABLE. + * + * It has never meant setting security.* and trusted.* xattrs. + * + * We could also define fsmask as follows: + * 1. CAP_FS_MASK is the privilege to bypass all fs-related DAC permissions + * 2. The security.* and trusted.* xattrs are fs-related MAC permissions + */ + # define CAP_FS_MASK_B0 (CAP_TO_MASK(CAP_CHOWN) \ + | CAP_TO_MASK(CAP_MKNOD) \ | CAP_TO_MASK(CAP_DAC_OVERRIDE) \ | CAP_TO_MASK(CAP_DAC_READ_SEARCH) \ | CAP_TO_MASK(CAP_FOWNER) \ @@ -392,11 +406,12 @@ struct cpu_vfs_cap_data { # define CAP_EMPTY_SET ((kernel_cap_t){{ 0, 0 }}) # define CAP_FULL_SET ((kernel_cap_t){{ ~0, ~0 }}) # define CAP_INIT_EFF_SET ((kernel_cap_t){{ ~CAP_TO_MASK(CAP_SETPCAP), ~0 }}) -# define CAP_FS_SET ((kernel_cap_t){{ CAP_FS_MASK_B0, CAP_FS_MASK_B1 } }) +# define CAP_FS_SET ((kernel_cap_t){{ CAP_FS_MASK_B0 \ + | CAP_TO_MASK(CAP_LINUX_IMMUTABLE), \ + CAP_FS_MASK_B1 } }) # define CAP_NFSD_SET ((kernel_cap_t){{ CAP_FS_MASK_B0 \ - | CAP_TO_MASK(CAP_SYS_RESOURCE) \ - | CAP_TO_MASK(CAP_MKNOD), \ - CAP_FS_MASK_B1 } }) + | CAP_TO_MASK(CAP_SYS_RESOURCE), \ + CAP_FS_MASK_B1 } }) #endif /* _KERNEL_CAPABILITY_U32S != 2 */ -- 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/