Messages in this thread | | | Date | Thu, 9 Sep 2004 13:48:54 -0700 | From | Chris Wright <> | Subject | Re: [1/1][PATCH] nproc v2: netlink access to /proc information |
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* Stephen Smalley (sds@epoch.ncsc.mil) wrote: > Well, it isn't that easy, or at least I don't think it is. The problem > is that there is no way presently to convey the sender's security > credentials (beyond the existing uid, cap information), since the LSM > patches for adding security fields and hooks for managing skb security > fields were rejected. The best we can do at present is pass along the > sender pid, uid, and cap, and the security module can look up the pid if > it chooses to get the security field (but is naturally subject to races > in that situation). > > Most obvious place to hook would be nproc_ps_get_task; we could then > perform a check based on the sender's credentials and the target task's > credentials, and simply return NULL if permission is not granted for > that pair, thus skipping that task as if it didn't exist. That requires > propagating the sender's credentials down to that function. > > Untested patch below. > > Index: linux-2.6/include/linux/security.h > =================================================================== > RCS file: /nfshome/pal/CVS/linux-2.6/include/linux/security.h,v > retrieving revision 1.37 > diff -u -p -r1.37 security.h > --- linux-2.6/include/linux/security.h 16 Jun 2004 14:49:42 -0000 1.37 > +++ linux-2.6/include/linux/security.h 9 Sep 2004 19:38:23 -0000 > @@ -632,6 +632,13 @@ struct swap_info_struct; > * security attributes, e.g. for /proc/pid inodes. > * @p contains the task_struct for the task. > * @inode contains the inode structure for the inode. > + * @task_getstate: > + * Check permission before getting the state of a task. > + * @pid contains the pid of the requesting process. > + * @p contains the task_struct for the target task. > + * @uid contains the uid of the requesting process. > + * @caps contains the capability set of the requesting process. > + * Return 0 if permission is granted.
Why caps?
thanks, -chris -- Linux Security Modules http://lsm.immunix.org http://lsm.bkbits.net - 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/
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