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* selinux: wrap AVC stateStephen Smalley2018-03-201-122/+162
| | | | | | | | | | | | | | Wrap the AVC state within the selinux_state structure and pass it explicitly to all AVC functions. The AVC private state is encapsulated in a selinux_avc structure that is referenced from the selinux_state. This change should have no effect on SELinux behavior or APIs (userspace or LSM). Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Reviewed-by: James Morris <james.morris@microsoft.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: rename the {is,set}_enforcing() functionsPaul Moore2018-03-021-1/+1
| | | | | | | Rename is_enforcing() to enforcing_enabled() and enforcing_set() to set_enforcing(). Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: wrap global selinux stateStephen Smalley2018-03-021-6/+10
| | | | | | | | | | | | | | | | | Define a selinux state structure (struct selinux_state) for global SELinux state and pass it explicitly to all security server functions. The public portion of the structure contains state that is used throughout the SELinux code, such as the enforcing mode. The structure also contains a pointer to a selinux_ss structure whose definition is private to the security server and contains security server specific state such as the policy database and SID table. This change should have no effect on SELinux behavior or APIs (userspace or LSM). It merely wraps SELinux state and passes it explicitly as needed. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> [PM: minor fixups needed due to collisions with the SCTP patches] Signed-off-by: Paul Moore <paul@paul-moore.com>
* Merge tag 'selinux-pr-20170831' of ↵Linus Torvalds2017-09-121-9/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: "A relatively quiet period for SELinux, 11 patches with only two/three having any substantive changes. These noteworthy changes include another tweak to the NNP/nosuid handling, per-file labeling for cgroups, and an object class fix for AF_UNIX/SOCK_RAW sockets; the rest of the changes are minor tweaks or administrative updates (Stephen's email update explains the file explosion in the diffstat). Everything passes the selinux-testsuite" [ Also a couple of small patches from the security tree from Tetsuo Handa for Tomoyo and LSM cleanup. The separation of security policy updates wasn't all that clean - Linus ] * tag 'selinux-pr-20170831' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: constify nf_hook_ops selinux: allow per-file labeling for cgroupfs lsm_audit: update my email address selinux: update my email address MAINTAINERS: update the NetLabel and Labeled Networking information selinux: use GFP_NOWAIT in the AVC kmem_caches selinux: Generalize support for NNP/nosuid SELinux domain transitions selinux: genheaders should fail if too many permissions are defined selinux: update the selinux info in MAINTAINERS credits: update Paul Moore's info selinux: Assign proper class to PF_UNIX/SOCK_RAW sockets tomoyo: Update URLs in Documentation/admin-guide/LSM/tomoyo.rst LSM: Remove security_task_create() hook.
| * selinux: update my email addressStephen Smalley2017-08-171-1/+1
| | | | | | | | | | | | | | | | Update my email address since epoch.ncsc.mil no longer exists. MAINTAINERS and CREDITS are already correct. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * selinux: use GFP_NOWAIT in the AVC kmem_cachesMichal Hocko2017-08-081-8/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | There is a strange __GFP_NOMEMALLOC usage pattern in SELinux, specifically GFP_ATOMIC | __GFP_NOMEMALLOC which doesn't make much sense. GFP_ATOMIC on its own allows to access memory reserves while __GFP_NOMEMALLOC dictates we cannot use memory reserves. Replace this with the much more sane GFP_NOWAIT in the AVC code as we can tolerate memory allocation failures in that code. Signed-off-by: Michal Hocko <mhocko@kernel.org> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Paul Moore <paul@paul-moore.com>
* | selinux: remove AVC init audit log messageRichard Guy Briggs2017-09-051-2/+0
|/ | | | | | | | | | | | | | In the process of normalizing audit log messages, it was noticed that the AVC initialization code registered an audit log KERNEL record that didn't fit the standard format. In the process of attempting to normalize it it was determined that this record was not even necessary. Remove it. Ref: http://marc.info/?l=selinux&m=149614868525826&w=2 See: https://github.com/linux-audit/audit-kernel/issues/48 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Steve Grubb <sgrubb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* Merge branch 'next' of git://git.infradead.org/users/pcmoore/selinux into nextJames Morris2015-08-151-16/+402
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| * selinux: Augment BUG_ON assertion for secclass_map.Stephen Smalley2015-07-131-1/+2
| | | | | | | | | | | | | | Ensure that we catch any cases where tclass == 0. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <pmoore@redhat.com>
| * selinux: extended permissions for ioctlsJeff Vander Stoep2015-07-131-15/+400
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add extended permissions logic to selinux. Extended permissions provides additional permissions in 256 bit increments. Extend the generic ioctl permission check to use the extended permissions for per-command filtering. Source/target/class sets including the ioctl permission may additionally include a set of commands. Example: allowxperm <source> <target>:<class> ioctl unpriv_app_socket_cmds auditallowxperm <source> <target>:<class> ioctl priv_gpu_cmds Where unpriv_app_socket_cmds and priv_gpu_cmds are macros representing commonly granted sets of ioctl commands. When ioctl commands are omitted only the permissions are checked. This feature is intended to provide finer granularity for the ioctl permission that may be too imprecise. For example, the same driver may use ioctls to provide important and benign functionality such as driver version or socket type as well as dangerous capabilities such as debugging features, read/write/execute to physical memory or access to sensitive data. Per-command filtering provides a mechanism to reduce the attack surface of the kernel, and limit applications to the subset of commands required. The format of the policy binary has been modified to include ioctl commands, and the policy version number has been incremented to POLICYDB_VERSION_XPERMS_IOCTL=30 to account for the format change. The extended permissions logic is deliberately generic to allow components to be reused e.g. netlink filters Signed-off-by: Jeff Vander Stoep <jeffv@google.com> Acked-by: Nick Kralevich <nnk@google.com> Signed-off-by: Paul Moore <pmoore@redhat.com>
* | security/selinux: pass 'flags' arg to avc_audit() and avc_has_perm_flags()NeilBrown2015-05-111-1/+17
|/ | | | | | | | This allows MAY_NOT_BLOCK to be passed, in RCU-walk mode, through the new avc_has_perm_flags() to avc_audit() and thence the slow_avc_audit. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* selinux: remove unnecessary pointer reassignmentJeff Vander Stoep2015-04-071-4/+2
| | | | | | | | | | | Commit f01e1af445fa ("selinux: don't pass in NULL avd to avc_has_perm_noaudit") made this pointer reassignment unnecessary. Avd should continue to reference the stack-based copy. Signed-off-by: Jeff Vander Stoep <jeffv@google.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> [PM: tweaked subject line] Signed-off-by: Paul Moore <pmoore@redhat.com>
* selinux: Remove unused function avc_sidcmp()Rickard Strandqvist2015-02-041-5/+0
| | | | | | | | | | Remove the function avc_sidcmp() that is not used anywhere. This was partially found by using a static code analysis program called cppcheck. Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se> [PM: rewrite the patch subject line] Signed-off-by: Paul Moore <pmoore@redhat.com>
* selinux: Report permissive mode in avc: denied messages.Stephen Smalley2014-06-031-1/+6
| | | | | | | | | | We cannot presently tell from an avc: denied message whether access was in fact denied or was allowed due to global or per-domain permissive mode. Add a permissive= field to the avc message to reflect this information. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: Paul Moore <pmoore@redhat.com>
* selinux: remove 'flags' parameter from avc_audit()Linus Torvalds2013-10-041-1/+1
| | | | | | Now avc_audit() has no more users with that parameter. Remove it. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* selinux: avc_has_perm_flags has no more usersLinus Torvalds2013-10-041-6/+3
| | | | | | | | .. so get rid of it. The only indirect users were all the avc_has_perm() callers which just expanded to have a zero flags argument. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* hlist: drop the node parameter from iteratorsSasha Levin2013-02-281-13/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* selinux: tag avc cache alloc as non-criticalMel Gorman2012-08-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | Failing to allocate a cache entry will only harm performance not correctness. Do not consume valuable reserve pages for something like that. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Eric Paris <eparis@redhat.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: David S. Miller <davem@davemloft.net> Cc: Eric B Munson <emunson@mgebm.net> Cc: Mel Gorman <mgorman@suse.de> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: Neil Brown <neilb@suse.de> Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Xiaotian Feng <dfeng@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SELinux: avc: remove the useless fields in avc_add_callbackWanlong Gao2012-04-091-26/+6
| | | | | | | | | avc_add_callback now just used for registering reset functions in initcalls, and the callback functions just did reset operations. So, reducing the arguments to only one event is enough now. Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> Signed-off-by: Eric Paris <eparis@redhat.com>
* SELinux: replace weak GFP_ATOMIC to GFP_KERNEL in avc_add_callbackWanlong Gao2012-04-091-2/+2
| | | | | | | | | avc_add_callback now only called from initcalls, so replace the weak GFP_ATOMIC to GFP_KERNEL, and mark this function __init to make a warning when not been called from initcalls. Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> Signed-off-by: Eric Paris <eparis@redhat.com>
* SELinux: unify the selinux_audit_data and selinux_late_audit_dataEric Paris2012-04-091-16/+15
| | | | | | | | We no longer need the distinction. We only need data after we decide to do an audit. So turn the "late" audit data into just "data" and remove what we currently have as "data". Signed-off-by: Eric Paris <eparis@redhat.com>
* LSM: do not initialize common_audit_data to 0Eric Paris2012-04-091-1/+1
| | | | | | | It isn't needed. If you don't set the type of the data associated with that type it is a pretty obvious programming bug. So why waste the cycles? Signed-off-by: Eric Paris <eparis@redhat.com>
* LSM: remove the COMMON_AUDIT_DATA_INIT type expansionEric Paris2012-04-091-1/+1
| | | | | | Just open code it so grep on the source code works better. Signed-off-by: Eric Paris <eparis@redhat.com>
* SELinux: delay initialization of audit data in selinux_inode_permissionEric Paris2012-04-091-62/+1
| | | | | | | | | | | | | We pay a rather large overhead initializing the common_audit_data. Since we only need this information if we actually emit an audit message there is little need to set it up in the hot path. This patch splits the functionality of avc_has_perm() into avc_has_perm_noaudit(), avc_audit_required() and slow_avc_audit(). But we take care of setting up to audit between required() and the actual audit call. Thus saving measurable time in a hot path. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Eric Paris <eparis@redhat.com>
* lsm_audit: don't specify the audit pre/post callbacks in 'struct ↵Linus Torvalds2012-04-031-3/+1
| | | | | | | | | | | | | | | common_audit_data' It just bloats the audit data structure for no good reason, since the only time those fields are filled are just before calling the common_lsm_audit() function, which is also the only user of those fields. So just make them be the arguments to common_lsm_audit(), rather than bloating that structure that is passed around everywhere, and is initialized in hot paths. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SELinux: do not allocate stack space for AVC data unless neededEric Paris2012-04-031-12/+15
| | | | | | | | | | Instead of declaring the entire selinux_audit_data on the stack when we start an operation on declare it on the stack if we are going to use it. We know it's usefulness at the end of the security decision and can declare it there. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SELinux: remove avd from slow_avc_audit()Eric Paris2012-04-031-2/+2
| | | | | | | We don't use the argument, so remove it. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* LSM: shrink sizeof LSM specific portion of common_audit_dataEric Paris2012-04-031-16/+18
| | | | | | | | | | | | Linus found that the gigantic size of the common audit data caused a big perf hit on something as simple as running stat() in a loop. This patch requires LSMs to declare the LSM specific portion separately rather than doing it in a union. Thus each LSM can be responsible for shrinking their portion and don't have to pay a penalty just because other LSMs have a bigger space requirement. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* selinux: inline avc_audit() and avc_has_perm_noaudit() into callerLinus Torvalds2012-03-311-2/+2
| | | | | | | | | | | | | | | | Now that all the slow-path code is gone from these functions, we can inline them into the main caller - avc_has_perm_flags(). Now the compiler can see that 'avc' is allocated on the stack for this case, which helps register pressure a bit. It also actually shrinks the total stack frame, because the stack frame that avc_has_perm_flags() always needed (for that 'avc' allocation) is now sufficient for the inlined functions too. Inlining isn't bad - but mindless inlining of cold code (see the previous commit) is. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* selinux: don't inline slow-path code into avc_has_perm_noaudit()Linus Torvalds2012-03-311-14/+38
| | | | | | | | | | | | | | | | | | | | | | The selinux AVC paths remain some of the hottest (and deepest) codepaths at filename lookup time, and we make it worse by having the slow path cases take up I$ and stack space even when they don't trigger. Gcc tends to always want to inline functions that are just called once - never mind that this might make for slower and worse code in the caller. So this tries to improve on it a bit by making the slow-path cases explicitly separate functions that are marked noinline, causing gcc to at least no longer allocate stack space for them unless they are actually called. It also seems to help register allocation a tiny bit, since gcc now doesn't take the slow case code into account. Uninlining the slow path may also allow us to inline the remaining hot path into the one caller that actually matters: avc_has_perm_flags(). I'll have to look at that separately, but both avc_audit() and avc_has_perm_noaudit() are now small and lean enough that inlining them may make sense. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* security: optimize avc_audit() common pathLinus Torvalds2012-03-231-29/+41
| | | | | | | | | | | | | | | | | | | | | avc_audit() did a lot of jumping around and had a big stack frame, all for the uncommon case. Split up the uncommon case (which we really can't make go fast anyway) into its own slow function, and mark the conditional branches appropriately for the common likely case. This causes avc_audit() to no longer show up as one of the hottest functions on the branch profiles (the new "perf -b" thing), and makes the cycle profiles look really nice and dense too. The whole audit path is still annoyingly very much one of the biggest costs of name lookup, so these things are worth optimizing for. I wish we could just tell people to turn it off, but realistically we do need it: we just need to make sure that the overhead of the necessary evil is as low as possible. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* selinux: don't transliterate MAY_NOT_BLOCK to IPERM_FLAG_RCUAl Viro2011-07-201-1/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* selinux: don't pass in NULL avd to avc_has_perm_noauditLinus Torvalds2011-05-271-10/+2
| | | | | | | | | | | | | | Right now security_get_user_sids() will pass in a NULL avd pointer to avc_has_perm_noaudit(), which then forces that function to have a dummy entry for that case and just generally test it. Don't do it. The normal callers all pass a real avd pointer, and this helper function is incredibly hot. So don't make avc_has_perm_noaudit() do conditional stuff that isn't needed for the common case. This also avoids some duplicated stack space. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'master' of git://git.infradead.org/users/eparis/selinux into ↵James Morris2011-05-241-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | for-linus Conflicts: lib/flex_array.c security/selinux/avc.c security/selinux/hooks.c security/selinux/ss/policydb.c security/smack/smack_lsm.c Manually resolve conflicts. Signed-off-by: James Morris <jmorris@namei.org>
| * LSM: split LSM_AUDIT_DATA_FS into _PATH and _INODEEric Paris2011-04-261-1/+1
| | | | | | | | | | | | | | | | | | | | The lsm common audit code has wacky contortions making sure which pieces of information are set based on if it was given a path, dentry, or inode. Split this into path and inode to get rid of some of the code complexity. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com>
| * SELINUX: Make selinux cache VFS RCU walks safeEric Paris2011-04-251-7/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that the security modules can decide whether they support the dcache RCU walk or not it's possible to make selinux a bit more RCU friendly. The SELinux AVC and security server access decision code is RCU safe. A specific piece of the LSM audit code may not be RCU safe. This patch makes the VFS RCU walk retry if it would hit the non RCU safe chunk of code. It will normally just work under RCU. This is done simply by passing the VFS RCU state as a flag down into the avc_audit() code and returning ECHILD there if it would have an issue. Based-on-patch-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Eric Paris <eparis@redhat.com>
* | selinux: avoid unnecessary avc cache stat hit countLinus Torvalds2011-05-201-5/+4
| | | | | | | | | | | | | | | | | | | | There is no point in counting hits - we can calculate it from the number of lookups and misses. This makes the avc statistics a bit smaller, and makes the code generation better too. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | selinux: de-crapify avc cache stat code generationLinus Torvalds2011-05-201-5/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | You can turn off the avc cache stats, but distributions seem to not do that (perhaps because several performance tuning how-to's talk about the avc cache statistics). Which is sad, because the code it generates is truly horrendous, with the statistics update being sandwitched between get_cpu/put_cpu which in turn causes preemption disables etc. We're talking ten+ instructions just to increment a per-cpu variable in some pretty hot code. Fix the craziness by just using 'this_cpu_inc()' instead. Suddenly we only need a single 'inc' instruction to increment the statistics. This is quite noticeable in the incredibly hot avc_has_perm_noaudit() function (which triggers all the statistics by virtue of doing an avc_lookup() call). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | SELINUX: Make selinux cache VFS RCU walks safeEric Paris2011-04-261-7/+29
|/ | | | | | | | | | | | | | | | | Now that the security modules can decide whether they support the dcache RCU walk or not it's possible to make selinux a bit more RCU friendly. The SELinux AVC and security server access decision code is RCU safe. A specific piece of the LSM audit code may not be RCU safe. This patch makes the VFS RCU walk retry if it would hit the non RCU safe chunk of code. It will normally just work under RCU. This is done simply by passing the VFS RCU state as a flag down into the avc_audit() code and returning ECHILD there if it would have an issue. Based-on-patch-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SELinux: special dontaudit for access checksEric Paris2010-08-021-2/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently there are a number of applications (nautilus being the main one) which calls access() on files in order to determine how they should be displayed. It is normal and expected that nautilus will want to see if files are executable or if they are really read/write-able. access() should return the real permission. SELinux policy checks are done in access() and can result in lots of AVC denials as policy denies RWX on files which DAC allows. Currently SELinux must dontaudit actual attempts to read/write/execute a file in order to silence these messages (and not flood the logs.) But dontaudit rules like that can hide real attacks. This patch addes a new common file permission audit_access. This permission is special in that it is meaningless and should never show up in an allow rule. Instead the only place this permission has meaning is in a dontaudit rule like so: dontaudit nautilus_t sbin_t:file audit_access With such a rule if nautilus just checks access() we will still get denied and thus userspace will still get the correct answer but we will not log the denial. If nautilus attempted to actually perform one of the forbidden actions (rather than just querying access(2) about it) we would still log a denial. This type of dontaudit rule should be used sparingly, as it could be a method for an attacker to probe the system permissions without detection. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* selinux: remove all rcu head initializationsPaul E. McKenney2010-08-021-1/+0
| | | | | | | | | | | | | Remove all rcu head inits. We don't care about the RCU head state before passing it to call_rcu() anyway. Only leave the "on_stack" variants so debugobjects can keep track of objects on stack. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Reviewed-by: James Morris <jmorris@namei.org> Cc: Eric Paris <eparis@parisplace.org> Signed-off-by: James Morris <jmorris@namei.org>
* LSM Audit: rename LSM_AUDIT_NO_AUDIT to LSM_AUDIT_DATA_NONEEric Paris2010-04-281-2/+1
| | | | | | | | | | Most of the LSM common audit work uses LSM_AUDIT_DATA_* for the naming. This was not so for LSM_AUDIT_NO_AUDIT which means the generic initializer cannot be used. This patch just renames the flag so the generic initializer can be used. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* Merge branch 'for-next' into for-linusJiri Kosina2010-03-081-3/+3
|\ | | | | | | | | | | | | | | | | Conflicts: Documentation/filesystems/proc.txt arch/arm/mach-u300/include/mach/debug-macro.S drivers/net/qlge/qlge_ethtool.c drivers/net/qlge/qlge_main.c drivers/net/typhoon.c
| * fix comment typos in avc.cJustin P. Mattock2010-02-051-3/+3
| | | | | | | | | | Signed-off-by: Justin P. Mattock <justinmattock@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | selinux: Only audit permissions specified in policyStephen Smalley2010-02-021-10/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Only audit the permissions specified by the policy rules. Before: type=AVC msg=audit(01/28/2010 14:30:46.690:3250) : avc: denied { read append } for pid=14092 comm=foo name=test_file dev=dm-1 ino=132932 scontext=unconfined_u:unconfined_r:load_policy_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:rpm_tmp_t:s0 tclass=file After: type=AVC msg=audit(01/28/2010 14:52:37.448:26) : avc: denied { append } for pid=1917 comm=foo name=test_file dev=dm-1 ino=132932 scontext=unconfined_u:unconfined_r:load_policy_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:rpm_tmp_t:s0 tclass=file Reference: https://bugzilla.redhat.com/show_bug.cgi?id=558499 Reported-by: Tom London <selinux@gmail.com> Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* | selinux: change the handling of unknown classesStephen Smalley2010-01-171-4/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | If allow_unknown==deny, SELinux treats an undefined kernel security class as an error condition rather than as a typical permission denial and thus does not allow permissions on undefined classes even when in permissive mode. Change the SELinux logic so that this case is handled as a typical permission denial, subject to the usual permissive mode and permissive domain handling. Also drop the 'requested' argument from security_compute_av() and helpers as it is a legacy of the original security server interface and is unused. Changes: - Handle permissive domains consistently by moving up the test for a permissive domain. - Make security_compute_av_user() consistent with security_compute_av(); the only difference now is that security_compute_av() performs mapping between the kernel-private class and permission indices and the policy values. In the userspace case, this mapping is handled by libselinux. - Moved avd_init inside the policy lock. Based in part on a patch by Paul Moore <paul.moore@hp.com>. Reported-by: Andrew Worsley <amworsley@gmail.com> Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov> Reviewed-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: print denials for buggy kernel with unknown permsEric Paris2009-11-241-1/+1
| | | | | | | | | | | | | | | | | Historically we've seen cases where permissions are requested for classes where they do not exist. In particular we have seen CIFS forget to set i_mode to indicate it is a directory so when we later check something like remove_name we have problems since it wasn't defined in tclass file. This used to result in a avc which included the permission 0x2000 or something. Currently the kernel will deny the operations (good thing) but will not print ANY information (bad thing). First the auditdeny field is no extended to include unknown permissions. After that is fixed the logic in avc_dump_query to output this information isn't right since it will remove the permission from the av and print the phrase "<NULL>". This takes us back to the behavior before the classmap rewrite. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* selinux: dynamic class/perm discoveryStephen Smalley2009-10-071-68/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Modify SELinux to dynamically discover class and permission values upon policy load, based on the dynamic object class/perm discovery logic from libselinux. A mapping is created between kernel-private class and permission indices used outside the security server and the policy values used within the security server. The mappings are only applied upon kernel-internal computations; similar mappings for the private indices of userspace object managers is handled on a per-object manager basis by the userspace AVC. The interfaces for compute_av and transition_sid are split for kernel vs. userspace; the userspace functions are distinguished by a _user suffix. The kernel-private class indices are no longer tied to the policy values and thus do not need to skip indices for userspace classes; thus the kernel class index values are compressed. The flask.h definitions were regenerated by deleting the userspace classes from refpolicy's definitions and then regenerating the headers. Going forward, we can just maintain the flask.h, av_permissions.h, and classmap.h definitions separately from policy as they are no longer tied to the policy values. The next patch introduces a utility to automate generation of flask.h and av_permissions.h from the classmap.h definitions. The older kernel class and permission string tables are removed and replaced by a single security class mapping table that is walked at policy load to generate the mapping. The old kernel class validation logic is completely replaced by the mapping logic. The handle unknown logic is reworked. reject_unknown=1 is handled when the mappings are computed at policy load time, similar to the old handling by the class validation logic. allow_unknown=1 is handled when computing and mapping decisions - if the permission was not able to be mapped (i.e. undefined, mapped to zero), then it is automatically added to the allowed vector. If the class was not able to be mapped (i.e. undefined, mapped to zero), then all permissions are allowed for it if allow_unknown=1. avc_audit leverages the new security class mapping table to lookup the class and permission names from the kernel-private indices. The mdp program is updated to use the new table when generating the class definitions and allow rules for a minimal boot policy for the kernel. It should be noted that this policy will not include any userspace classes, nor will its policy index values for the kernel classes correspond with the ones in refpolicy (they will instead match the kernel-private indices). Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: do not destroy the avc_cache_nodepEric Paris2009-09-231-4/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The security_ops reset done when SELinux is disabled at run time is done after the avc cache is freed and after the kmem_cache for the avc is also freed. This means that between the time the selinux disable code destroys the avc_node_cachep another process could make a security request and could try to allocate from the cache. We are just going to leave the cachep around, like we always have. SELinux: Disabled at runtime. BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff81122537>] kmem_cache_alloc+0x9a/0x185 PGD 0 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC last sysfs file: CPU 1 Modules linked in: Pid: 12, comm: khelper Not tainted 2.6.31-tip-05525-g0eeacc6-dirty #14819 System Product Name RIP: 0010:[<ffffffff81122537>] [<ffffffff81122537>] kmem_cache_alloc+0x9a/0x185 RSP: 0018:ffff88003f9258b0 EFLAGS: 00010086 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000078c0129e RDX: 0000000000000000 RSI: ffffffff8130b626 RDI: ffffffff81122528 RBP: ffff88003f925900 R08: 0000000078c0129e R09: 0000000000000001 R10: 0000000000000000 R11: 0000000078c0129e R12: 0000000000000246 R13: 0000000000008020 R14: ffff88003f8586d8 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff880002b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b CR2: 0000000000000000 CR3: 0000000001001000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: ffffffff827bd420 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process khelper (pid: 12, threadinfo ffff88003f924000, task ffff88003f928000) Stack: 0000000000000246 0000802000000246 ffffffff8130b626 0000000000000001 <0> 0000000078c0129e 0000000000000000 ffff88003f925a70 0000000000000002 <0> 0000000000000001 0000000000000001 ffff88003f925960 ffffffff8130b626 Call Trace: [<ffffffff8130b626>] ? avc_alloc_node+0x36/0x273 [<ffffffff8130b626>] avc_alloc_node+0x36/0x273 [<ffffffff8130b545>] ? avc_latest_notif_update+0x7d/0x9e [<ffffffff8130b8b4>] avc_insert+0x51/0x18d [<ffffffff8130bcce>] avc_has_perm_noaudit+0x9d/0x128 [<ffffffff8130bf20>] avc_has_perm+0x45/0x88 [<ffffffff8130f99d>] current_has_perm+0x52/0x6d [<ffffffff8130fbb2>] selinux_task_create+0x2f/0x45 [<ffffffff81303bf7>] security_task_create+0x29/0x3f [<ffffffff8105c6ba>] copy_process+0x82/0xdf0 [<ffffffff81091578>] ? register_lock_class+0x2f/0x36c [<ffffffff81091a13>] ? mark_lock+0x2e/0x1e1 [<ffffffff8105d596>] do_fork+0x16e/0x382 [<ffffffff81091578>] ? register_lock_class+0x2f/0x36c [<ffffffff810d9166>] ? probe_workqueue_execution+0x57/0xf9 [<ffffffff81091a13>] ? mark_lock+0x2e/0x1e1 [<ffffffff810d9166>] ? probe_workqueue_execution+0x57/0xf9 [<ffffffff8100cdb2>] kernel_thread+0x82/0xe0 [<ffffffff81078b1f>] ? ____call_usermodehelper+0x0/0x139 [<ffffffff8100ce10>] ? child_rip+0x0/0x20 [<ffffffff81078aea>] ? __call_usermodehelper+0x65/0x9a [<ffffffff8107a5c7>] run_workqueue+0x171/0x27e [<ffffffff8107a573>] ? run_workqueue+0x11d/0x27e [<ffffffff81078a85>] ? __call_usermodehelper+0x0/0x9a [<ffffffff8107a7bc>] worker_thread+0xe8/0x10f [<ffffffff810808e2>] ? autoremove_wake_function+0x0/0x63 [<ffffffff8107a6d4>] ? worker_thread+0x0/0x10f [<ffffffff8108042e>] kthread+0x91/0x99 [<ffffffff8100ce1a>] child_rip+0xa/0x20 [<ffffffff8100c754>] ? restore_args+0x0/0x30 [<ffffffff8108039d>] ? kthread+0x0/0x99 [<ffffffff8100ce10>] ? child_rip+0x0/0x20 Code: 0f 85 99 00 00 00 9c 58 66 66 90 66 90 49 89 c4 fa 66 66 90 66 66 90 e8 83 34 fb ff e8 d7 e9 26 00 48 98 49 8b 94 c6 10 01 00 00 <48> 8b 1a 44 8b 7a 18 48 85 db 74 0f 8b 42 14 48 8b 04 c3 ff 42 RIP [<ffffffff81122537>] kmem_cache_alloc+0x9a/0x185 RSP <ffff88003f9258b0> CR2: 0000000000000000 ---[ end trace 42f41a982344e606 ]--- Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: flush the avc before disabling SELinuxEric Paris2009-09-141-0/+2
| | | | | | | | Before SELinux is disabled at boot it can create AVC entries. This patch will flush those entries before disabling SELinux. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-23 05:08:52 +0100