aboutsummaryrefslogtreecommitdiffstats
path: root/security/selinux
Commit message (Collapse)AuthorAge
* selinux: Fix send_sigiotask hookStephen Smalley2009-05-04
| | | | | | | | | | | The CRED patch incorrectly converted the SELinux send_sigiotask hook to use the current task SID rather than the target task SID in its permission check, yielding the wrong permission check. This fixes the hook function. Detected by the ltp selinux testsuite and confirmed to correct the test failure. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* selinux: Remove the "compat_net" compatibility codePaul Moore2009-03-28
| | | | | | | | | | The SELinux "compat_net" is marked as deprecated, the time has come to finally remove it from the kernel. Further code simplifications are likely in the future, but this patch was intended to be a simple, straight-up removal of the compat_net code. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
* netlabel: Label incoming TCP connections correctly in SELinuxPaul Moore2009-03-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current NetLabel/SELinux behavior for incoming TCP connections works but only through a series of happy coincidences that rely on the limited nature of standard CIPSO (only able to convey MLS attributes) and the write equality imposed by the SELinux MLS constraints. The problem is that network sockets created as the result of an incoming TCP connection were not on-the-wire labeled based on the security attributes of the parent socket but rather based on the wire label of the remote peer. The issue had to do with how IP options were managed as part of the network stack and where the LSM hooks were in relation to the code which set the IP options on these newly created child sockets. While NetLabel/SELinux did correctly set the socket's on-the-wire label it was promptly cleared by the network stack and reset based on the IP options of the remote peer. This patch, in conjunction with a prior patch that adjusted the LSM hook locations, works to set the correct on-the-wire label format for new incoming connections through the security_inet_conn_request() hook. Besides the correct behavior there are many advantages to this change, the most significant is that all of the NetLabel socket labeling code in SELinux now lives in hooks which can return error codes to the core stack which allows us to finally get ride of the selinux_netlbl_inode_permission() logic which greatly simplfies the NetLabel/SELinux glue code. In the process of developing this patch I also ran into a small handful of AF_INET6 cleanliness issues that have been fixed which should make the code safer and easier to extend in the future. Signed-off-by: Paul Moore <paul.moore@hp.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: James Morris <jmorris@namei.org>
* Merge branch 'master' into nextJames Morris2009-03-23
|\
| * selinux: Fix a panic in selinux_netlbl_inode_permission()Paul Moore2009-03-01
| | | | | | | | | | | | | | | | | | | | | | Rick McNeal from LSI identified a panic in selinux_netlbl_inode_permission() caused by a certain sequence of SUNRPC operations. The problem appears to be due to the lack of NULL pointer checking in the function; this patch adds the pointer checks so the function will exit safely in the cases where the socket is not completely initialized. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
| * selinux: Fix the NetLabel glue code for setsockopt()Paul Moore2009-02-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At some point we (okay, I) managed to break the ability for users to use the setsockopt() syscall to set IPv4 options when NetLabel was not active on the socket in question. The problem was noticed by someone trying to use the "-R" (record route) option of ping: # ping -R 10.0.0.1 ping: record route: No message of desired type The solution is relatively simple, we catch the unlabeled socket case and clear the error code, allowing the operation to succeed. Please note that we still deny users the ability to override IPv4 options on socket's which have NetLabel labeling active; this is done to ensure the labeling remains intact. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
* | SELinux: inode_doinit_with_dentry drop no dentry printkEric Paris2009-03-09
| | | | | | | | | | | | | | | | | | | | Drop the printk message when an inode is found without an associated dentry. This should only happen when userspace can't be accessing those inodes and those labels will get set correctly on the next d_instantiate. Thus there is no reason to send this message. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | SELinux: new permission between tty audit and audit socketEric Paris2009-03-05
| | | | | | | | | | | | | | | | | | New selinux permission to separate the ability to turn on tty auditing from the ability to set audit rules. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* | SELinux: open perm for sock filesEric Paris2009-03-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When I did open permissions I didn't think any sockets would have an open. Turns out AF_UNIX sockets can have an open when they are bound to the filesystem namespace. This patch adds a new SOCK_FILE__OPEN permission. It's safe to add this as the open perms are already predicated on capabilities and capabilities means we have unknown perm handling so systems should be as backwards compatible as the policy wants them to be. https://bugzilla.redhat.com/show_bug.cgi?id=475224 Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* | SELinux: convert the avc cache hash list to an hlistEric Paris2009-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | We do not need O(1) access to the tail of the avc cache lists and so we are wasting lots of space using struct list_head instead of struct hlist_head. This patch converts the avc cache to use hlists in which there is a single pointer from the head which saves us about 4k of global memory. Resulted in about a 1.5% decrease in time spent in avc_has_perm_noaudit based on oprofile sampling of tbench. Although likely within the noise.... Signed-off-by: Eric Paris <eparis@redhat.com> Reviewed-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
* | SELinux: code readability with avc_cacheEric Paris2009-02-13
| | | | | | | | | | | | | | | | | | The code making use of struct avc_cache was not easy to read thanks to liberal use of &avc_cache.{slots_lock,slots}[hvalue] throughout. This patch simply creates local pointers and uses those instead of the long global names. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | SELinux: remove unused av.decided fieldEric Paris2009-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It appears there was an intention to have the security server only decide certain permissions and leave other for later as some sort of a portential performance win. We are currently always deciding all 32 bits of permissions and this is a useless couple of branches and wasted space. This patch completely drops the av.decided concept. This in a 17% reduction in the time spent in avc_has_perm_noaudit based on oprofile sampling of a tbench benchmark. Signed-off-by: Eric Paris <eparis@redhat.com> Reviewed-by: Paul Moore <paul.moore@hp.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* | SELinux: more careful use of avd in avc_has_perm_noauditEric Paris2009-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | we are often needlessly jumping through hoops when it comes to avd entries in avc_has_perm_noaudit and we have extra initialization and memcpy which are just wasting performance. Try to clean the function up a bit. This patch resulted in a 13% drop in time spent in avc_has_perm_noaudit in my oprofile sampling of a tbench benchmark. Signed-off-by: Eric Paris <eparis@redhat.com> Reviewed-by: Paul Moore <paul.moore@hp.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* | SELinux: remove the unused ae.usedEric Paris2009-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently SELinux code has an atomic which was intended to track how many times an avc entry was used and to evict entries when they haven't been used recently. Instead we never let this atomic get above 1 and evict when it is first checked for eviction since it hits zero. This is a total waste of time so I'm completely dropping ae.used. This change resulted in about a 3% faster avc_has_perm_noaudit when running oprofile against a tbench benchmark. Signed-off-by: Eric Paris <eparis@redhat.com> Reviewed by: Paul Moore <paul.moore@hp.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* | SELinux: check seqno when updating an avc_nodeEric Paris2009-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | The avc update node callbacks do not check the seqno of the caller with the seqno of the node found. It is possible that a policy change could happen (although almost impossibly unlikely) in which a permissive or permissive_domain decision is not valid for the entry found. Simply pass and check that the seqno of the caller and the seqno of the node found match. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* | SELinux: NULL terminate al contexts from diskEric Paris2009-02-13
| | | | | | | | | | | | | | | | | | | | When a context is pulled in from disk we don't know that it is null terminated. This patch forecebly null terminates contexts when we pull them from disk. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* | SELinux: better printk when file with invalid label foundEric Paris2009-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently when an inode is read into the kernel with an invalid label string (can often happen with removable media) we output a string like: SELinux: inode_doinit_with_dentry: context_to_sid([SOME INVALID LABEL]) returned -22 dor dev=[blah] ino=[blah] Which is all but incomprehensible to all but a couple of us. Instead, on EINVAL only, I plan to output a much more user friendly string and I plan to ratelimit the printk since many of these could be generated very rapidly. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* | SELinux: call capabilities code directoryEric Paris2009-02-13
| | | | | | | | | | | | | | | | | | | | | | For cleanliness and efficiency remove all calls to secondary-> and instead call capabilities code directly. capabilities are the only module that selinux stacks with and so the code should not indicate that other stacking might be possible. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* | Merge branch 'master' into nextJames Morris2009-02-05
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: fs/namei.c Manually merged per: diff --cc fs/namei.c index 734f2b5,bbc15c2..0000000 --- a/fs/namei.c +++ b/fs/namei.c @@@ -860,9 -848,8 +849,10 @@@ static int __link_path_walk(const char nd->flags |= LOOKUP_CONTINUE; err = exec_permission_lite(inode); if (err == -EAGAIN) - err = vfs_permission(nd, MAY_EXEC); + err = inode_permission(nd->path.dentry->d_inode, + MAY_EXEC); + if (!err) + err = ima_path_check(&nd->path, MAY_EXEC); if (err) break; @@@ -1525,14 -1506,9 +1509,14 @@@ int may_open(struct path *path, int acc flag &= ~O_TRUNC; } - error = vfs_permission(nd, acc_mode); + error = inode_permission(inode, acc_mode); if (error) return error; + - error = ima_path_check(&nd->path, ++ error = ima_path_check(path, + acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC)); + if (error) + return error; /* * An append-only file must be opened in append mode for writing. */ Signed-off-by: James Morris <jmorris@namei.org>
| * Merge branch 'next' into for-linusJames Morris2009-01-06
| |\
| * \ Merge branch 'for-linus' of ↵Linus Torvalds2009-01-05
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: inotify: fix type errors in interfaces fix breakage in reiserfs_new_inode() fix the treatment of jfs special inodes vfs: remove duplicate code in get_fs_type() add a vfs_fsync helper sys_execve and sys_uselib do not call into fsnotify zero i_uid/i_gid on inode allocation inode->i_op is never NULL ntfs: don't NULL i_op isofs check for NULL ->i_op in root directory is dead code affs: do not zero ->i_op kill suid bit only for regular files vfs: lseek(fd, 0, SEEK_CUR) race condition
| | * | zero i_uid/i_gid on inode allocationAl Viro2009-01-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ... and don't bother in callers. Don't bother with zeroing i_blocks, while we are at it - it's already been zeroed. i_mode is not worth the effort; it has no common default value. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | audit: validate comparison operations, store them in sane formAl Viro2009-01-04
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't store the field->op in the messy (and very inconvenient for e.g. audit_comparator()) form; translate to dense set of values and do full validation of userland-submitted value while we are at it. ->audit_init_rule() and ->audit_match_rule() get new values now; in-tree instances updated. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits.: coreRusty Russell2008-12-31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup In future, all cpumask ops will only be valid (in general) for bit numbers < nr_cpu_ids. So use that instead of NR_CPUS in iterators and other comparisons. This is always safe: no cpu number can be >= nr_cpu_ids, and nr_cpu_ids is initialized to NR_CPUS at boot. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Mike Travis <travis@sgi.com> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: James Morris <jmorris@namei.org> Cc: Eric Biederman <ebiederm@xmission.com>
* | | selinux: remove hooks which simply defer to capabilitiesJames Morris2009-02-01
| | | | | | | | | | | | | | | | | | | | | | | | Remove SELinux hooks which do nothing except defer to the capabilites hooks (or in one case, replicates the function). Signed-off-by: James Morris <jmorris@namei.org> Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
* | | selinux: remove secondary ops call to shm_shmatJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to shm_shmat, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to unix_stream_connectJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to unix_stream_connect, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to task_killJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to task_kill, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to task_setrlimitJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to task_setrlimit, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove unused cred_commit hookJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove unused cred_commit hook from SELinux. This currently calls into the capabilities hook, which is a noop. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to task_createJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to task_create, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to file_mprotectJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to file_mprotect, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to inode_setattrJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to inode_setattr, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to inode_permissionJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to inode_permission, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to inode_follow_linkJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to inode_follow_link, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to inode_mknodJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to inode_mknod, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to inode_unlinkJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to inode_unlink, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to inode_linkJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to inode_link, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to sb_umountJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to sb_umount, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to sb_mountJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to sb_mount, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to bprm_committed_credsJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to bprm_committed_creds, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove secondary ops call to bprm_committing_credsJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove secondary ops call to bprm_committing_creds, which is a noop in capabilities. Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | selinux: remove unused bprm_check_security hookJames Morris2009-01-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove unused bprm_check_security hook from SELinux. This currently calls into the capabilities hook, which is a noop. Acked-by: Eric Paris <eparis@redhat.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | SELinux: Unify context mount and genfs behaviorDavid P. Quigley2009-01-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Context mounts and genfs labeled file systems behave differently with respect to setting file system labels. This patch brings genfs labeled file systems in line with context mounts in that setxattr calls to them should return EOPNOTSUPP and fscreate calls will be ignored. Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@macbook.localdomain>
* | | SELinux: Add new security mount option to indicate security label support.David P. Quigley2009-01-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no easy way to tell if a file system supports SELinux security labeling. Because of this a new flag is being added to the super block security structure to indicate that the particular super block supports labeling. This flag is set for file systems using the xattr, task, and transition labeling methods unless that behavior is overridden by context mounts. Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@macbook.localdomain>
* | | SELinux: Condense super block security structure flags and cleanup necessary ↵David P. Quigley2009-01-18
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | code. The super block security structure currently has three fields for what are essentially flags. The flags field is used for mount options while two other char fields are used for initialization and proc flags. These latter two fields are essentially bit fields since the only used values are 0 and 1. These fields have been collapsed into the flags field and new bit masks have been added for them. The code is also fixed to work with these new flags. Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@macbook.localdomain>
* | CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #3]David Howells2009-01-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a regression in cap_capable() due to: commit 3b11a1decef07c19443d24ae926982bc8ec9f4c0 Author: David Howells <dhowells@redhat.com> Date: Fri Nov 14 10:39:26 2008 +1100 CRED: Differentiate objective and effective subjective credentials on a task The problem is that the above patch allows a process to have two sets of credentials, and for the most part uses the subjective credentials when accessing current's creds. There is, however, one exception: cap_capable(), and thus capable(), uses the real/objective credentials of the target task, whether or not it is the current task. Ordinarily this doesn't matter, since usually the two cred pointers in current point to the same set of creds. However, sys_faccessat() makes use of this facility to override the credentials of the calling process to make its test, without affecting the creds as seen from other processes. One of the things sys_faccessat() does is to make an adjustment to the effective capabilities mask, which cap_capable(), as it stands, then ignores. The affected capability check is in generic_permission(): if (!(mask & MAY_EXEC) || execute_ok(inode)) if (capable(CAP_DAC_OVERRIDE)) return 0; This change passes the set of credentials to be tested down into the commoncap and SELinux code. The security functions called by capable() and has_capability() select the appropriate set of credentials from the process being checked. This can be tested by compiling the following program from the XFS testsuite: /* * t_access_root.c - trivial test program to show permission bug. * * Written by Michael Kerrisk - copyright ownership not pursued. * Sourced from: http://linux.derkeiler.com/Mailing-Lists/Kernel/2003-10/6030.html */ #include <limits.h> #include <unistd.h> #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <sys/stat.h> #define UID 500 #define GID 100 #define PERM 0 #define TESTPATH "/tmp/t_access" static void errExit(char *msg) { perror(msg); exit(EXIT_FAILURE); } /* errExit */ static void accessTest(char *file, int mask, char *mstr) { printf("access(%s, %s) returns %d\n", file, mstr, access(file, mask)); } /* accessTest */ int main(int argc, char *argv[]) { int fd, perm, uid, gid; char *testpath; char cmd[PATH_MAX + 20]; testpath = (argc > 1) ? argv[1] : TESTPATH; perm = (argc > 2) ? strtoul(argv[2], NULL, 8) : PERM; uid = (argc > 3) ? atoi(argv[3]) : UID; gid = (argc > 4) ? atoi(argv[4]) : GID; unlink(testpath); fd = open(testpath, O_RDWR | O_CREAT, 0); if (fd == -1) errExit("open"); if (fchown(fd, uid, gid) == -1) errExit("fchown"); if (fchmod(fd, perm) == -1) errExit("fchmod"); close(fd); snprintf(cmd, sizeof(cmd), "ls -l %s", testpath); system(cmd); if (seteuid(uid) == -1) errExit("seteuid"); accessTest(testpath, 0, "0"); accessTest(testpath, R_OK, "R_OK"); accessTest(testpath, W_OK, "W_OK"); accessTest(testpath, X_OK, "X_OK"); accessTest(testpath, R_OK | W_OK, "R_OK | W_OK"); accessTest(testpath, R_OK | X_OK, "R_OK | X_OK"); accessTest(testpath, W_OK | X_OK, "W_OK | X_OK"); accessTest(testpath, R_OK | W_OK | X_OK, "R_OK | W_OK | X_OK"); exit(EXIT_SUCCESS); } /* main */ This can be run against an Ext3 filesystem as well as against an XFS filesystem. If successful, it will show: [root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043 ---------- 1 dhowells dhowells 0 2008-12-31 03:00 /tmp/xxx access(/tmp/xxx, 0) returns 0 access(/tmp/xxx, R_OK) returns 0 access(/tmp/xxx, W_OK) returns 0 access(/tmp/xxx, X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK) returns 0 access(/tmp/xxx, R_OK | X_OK) returns -1 access(/tmp/xxx, W_OK | X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1 If unsuccessful, it will show: [root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043 ---------- 1 dhowells dhowells 0 2008-12-31 02:56 /tmp/xxx access(/tmp/xxx, 0) returns 0 access(/tmp/xxx, R_OK) returns -1 access(/tmp/xxx, W_OK) returns -1 access(/tmp/xxx, X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK) returns -1 access(/tmp/xxx, R_OK | X_OK) returns -1 access(/tmp/xxx, W_OK | X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1 I've also tested the fix with the SELinux and syscalls LTP testsuites. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: J. Bruce Fields <bfields@citi.umich.edu> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* | Revert "CRED: Fix regression in cap_capable() as shown up by sys_faccessat() ↵James Morris2009-01-06
| | | | | | | | | | | | | | | | [ver #2]" This reverts commit 14eaddc967b16017d4a1a24d2be6c28ecbe06ed8. David has a better version to come.
* | SELinux: shrink sizeof av_inhert selinux_class_perm and contextEric Paris2009-01-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I started playing with pahole today and decided to put it against the selinux structures. Found we could save a little bit of space on x86_64 (and no harm on i686) just reorganizing some structs. Object size changes: av_inherit: 24 -> 16 selinux_class_perm: 48 -> 40 context: 80 -> 72 Admittedly there aren't many of av_inherit or selinux_class_perm's in the kernel (33 and 1 respectively) But the change to the size of struct context reverberate out a bit. I can get some hard number if they are needed, but I don't see why they would be. We do change which cacheline context->len and context->str would be on, but I don't see that as a problem since we are clearly going to have to load both if the context is to be of any value. I've run with the patch and don't seem to be having any problems. An example of what's going on using struct av_inherit would be: form: to: struct av_inherit { struct av_inherit { u16 tclass; const char **common_pts; const char **common_pts; u32 common_base; u32 common_base; u16 tclass; }; (notice all I did was move u16 tclass to the end of the struct instead of the beginning) Memory layout before the change: struct av_inherit { u16 tclass; /* 2 */ /* 6 bytes hole */ const char** common_pts; /* 8 */ u32 common_base; /* 4 */ /* 4 byes padding */ /* size: 24, cachelines: 1 */ /* sum members: 14, holes: 1, sum holes: 6 */ /* padding: 4 */ }; Memory layout after the change: struct av_inherit { const char ** common_pts; /* 8 */ u32 common_base; /* 4 */ u16 tclass; /* 2 */ /* 2 bytes padding */ /* size: 16, cachelines: 1 */ /* sum members: 14, holes: 0, sum holes: 0 */ /* padding: 2 */ }; Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | CRED: Fix regression in cap_capable() as shown up by sys_faccessat() [ver #2]David Howells2009-01-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a regression in cap_capable() due to: commit 5ff7711e635b32f0a1e558227d030c7e45b4a465 Author: David Howells <dhowells@redhat.com> Date: Wed Dec 31 02:52:28 2008 +0000 CRED: Differentiate objective and effective subjective credentials on a task The problem is that the above patch allows a process to have two sets of credentials, and for the most part uses the subjective credentials when accessing current's creds. There is, however, one exception: cap_capable(), and thus capable(), uses the real/objective credentials of the target task, whether or not it is the current task. Ordinarily this doesn't matter, since usually the two cred pointers in current point to the same set of creds. However, sys_faccessat() makes use of this facility to override the credentials of the calling process to make its test, without affecting the creds as seen from other processes. One of the things sys_faccessat() does is to make an adjustment to the effective capabilities mask, which cap_capable(), as it stands, then ignores. The affected capability check is in generic_permission(): if (!(mask & MAY_EXEC) || execute_ok(inode)) if (capable(CAP_DAC_OVERRIDE)) return 0; This change splits capable() from has_capability() down into the commoncap and SELinux code. The capable() security op now only deals with the current process, and uses the current process's subjective creds. A new security op - task_capable() - is introduced that can check any task's objective creds. strictly the capable() security op is superfluous with the presence of the task_capable() op, however it should be faster to call the capable() op since two fewer arguments need be passed down through the various layers. This can be tested by compiling the following program from the XFS testsuite: /* * t_access_root.c - trivial test program to show permission bug. * * Written by Michael Kerrisk - copyright ownership not pursued. * Sourced from: http://linux.derkeiler.com/Mailing-Lists/Kernel/2003-10/6030.html */ #include <limits.h> #include <unistd.h> #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <sys/stat.h> #define UID 500 #define GID 100 #define PERM 0 #define TESTPATH "/tmp/t_access" static void errExit(char *msg) { perror(msg); exit(EXIT_FAILURE); } /* errExit */ static void accessTest(char *file, int mask, char *mstr) { printf("access(%s, %s) returns %d\n", file, mstr, access(file, mask)); } /* accessTest */ int main(int argc, char *argv[]) { int fd, perm, uid, gid; char *testpath; char cmd[PATH_MAX + 20]; testpath = (argc > 1) ? argv[1] : TESTPATH; perm = (argc > 2) ? strtoul(argv[2], NULL, 8) : PERM; uid = (argc > 3) ? atoi(argv[3]) : UID; gid = (argc > 4) ? atoi(argv[4]) : GID; unlink(testpath); fd = open(testpath, O_RDWR | O_CREAT, 0); if (fd == -1) errExit("open"); if (fchown(fd, uid, gid) == -1) errExit("fchown"); if (fchmod(fd, perm) == -1) errExit("fchmod"); close(fd); snprintf(cmd, sizeof(cmd), "ls -l %s", testpath); system(cmd); if (seteuid(uid) == -1) errExit("seteuid"); accessTest(testpath, 0, "0"); accessTest(testpath, R_OK, "R_OK"); accessTest(testpath, W_OK, "W_OK"); accessTest(testpath, X_OK, "X_OK"); accessTest(testpath, R_OK | W_OK, "R_OK | W_OK"); accessTest(testpath, R_OK | X_OK, "R_OK | X_OK"); accessTest(testpath, W_OK | X_OK, "W_OK | X_OK"); accessTest(testpath, R_OK | W_OK | X_OK, "R_OK | W_OK | X_OK"); exit(EXIT_SUCCESS); } /* main */ This can be run against an Ext3 filesystem as well as against an XFS filesystem. If successful, it will show: [root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043 ---------- 1 dhowells dhowells 0 2008-12-31 03:00 /tmp/xxx access(/tmp/xxx, 0) returns 0 access(/tmp/xxx, R_OK) returns 0 access(/tmp/xxx, W_OK) returns 0 access(/tmp/xxx, X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK) returns 0 access(/tmp/xxx, R_OK | X_OK) returns -1 access(/tmp/xxx, W_OK | X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1 If unsuccessful, it will show: [root@andromeda src]# ./t_access_root /tmp/xxx 0 4043 4043 ---------- 1 dhowells dhowells 0 2008-12-31 02:56 /tmp/xxx access(/tmp/xxx, 0) returns 0 access(/tmp/xxx, R_OK) returns -1 access(/tmp/xxx, W_OK) returns -1 access(/tmp/xxx, X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK) returns -1 access(/tmp/xxx, R_OK | X_OK) returns -1 access(/tmp/xxx, W_OK | X_OK) returns -1 access(/tmp/xxx, R_OK | W_OK | X_OK) returns -1 I've also tested the fix with the SELinux and syscalls LTP testsuites. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-26 23:42:32 -0500