| From d11a29e323dfd141183cdc918e31acdff02ef450 Mon Sep 17 00:00:00 2001 |
| From: Serge E. Hallyn <serue@us.ibm.com> |
| Date: Mon, 13 Apr 2009 17:25:03 +0000 |
| Subject: add some long-missing capabilities to fs_mask |
| |
| From: Serge E. Hallyn <serue@us.ibm.com> |
| |
| 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 <izh1979@gmail.com> |
| Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> |
| Cc: stable@kernel.org |
| Cc: J. Bruce Fields <bfields@citi.umich.edu> |
| Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
| Signed-off-by: Chris Wright <chrisw@sous-sol.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| --- |
| include/linux/capability.h | 23 +++++++++++++++++++---- |
| 1 file changed, 19 insertions(+), 4 deletions(-) |
| |
| --- a/include/linux/capability.h |
| +++ b/include/linux/capability.h |
| @@ -366,7 +366,21 @@ typedef struct kernel_cap_struct { |
| #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) \ |
| @@ -381,11 +395,12 @@ typedef struct kernel_cap_struct { |
| # 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 */ |
| |
