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2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-4/+1
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11selinux: log raw contexts as untrusted stringsOndrej Mosnacek1-2/+8
These strings may come from untrusted sources (e.g. file xattrs) so they need to be properly escaped. Reproducer: # setenforce 0 # touch /tmp/test # setfattr -n security.selinux -v 'kuřecí řízek' /tmp/test # runcon system_u:system_r:sshd_t:s0 cat /tmp/test (look at the generated AVCs) Actual result: type=AVC [...] trawcon=kuřecí řízek Expected result: type=AVC [...] trawcon=6B75C5996563C3AD20C599C3AD7A656B Fixes: fede148324c3 ("selinux: log invalid contexts in AVCs") Cc: stable@vger.kernel.org # v5.1+ Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Acked-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-02-05selinux: fix avc audit messagesStephen Smalley1-3/+3
commit a2c513835bb6c6 ("selinux: inline some AVC functions used only once") introduced usage of audit_log_string() in place of audit_log_format() for fixed strings. However, audit_log_string() quotes the string. This breaks the avc audit message format and userspace audit parsers. Switch back to using audit_log_format(). Fixes: a2c513835bb6c6 ("selinux: inline some AVC functions used only once") Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-01-28selinux: replace BUG_ONs with WARN_ONs in avc.cOndrej Mosnacek1-2/+4
These checks are only guarding against programming errors that could silently grant too many permissions. These cases are better handled with WARN_ON(), since it doesn't really help much to crash the machine in this case. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-01-25selinux: log invalid contexts in AVCsOndrej Mosnacek1-0/+15
In case a file has an invalid context set, in an AVC record generated upon access to such file, the target context is always reported as unlabeled. This patch adds new optional fields to the AVC record (srawcon and trawcon) that report the actual context string if it differs from the one reported in scontext/tcontext. This is useful for diagnosing SELinux denials involving invalid contexts. To trigger an AVC that illustrates this situation: # setenforce 0 # touch /tmp/testfile # setfattr -n security.selinux -v system_u:object_r:banana_t:s0 /tmp/testfile # runcon system_u:system_r:sshd_t:s0 cat /tmp/testfile AVC before: type=AVC msg=audit(1547801083.248:11): avc: denied { open } for pid=1149 comm="cat" path="/tmp/testfile" dev="tmpfs" ino=6608 scontext=system_u:system_r:sshd_t:s0 tcontext=system_u:object_r:unlabeled_t:s15:c0.c1023 tclass=file permissive=1 AVC after: type=AVC msg=audit(1547801083.248:11): avc: denied { open } for pid=1149 comm="cat" path="/tmp/testfile" dev="tmpfs" ino=6608 scontext=system_u:system_r:sshd_t:s0 tcontext=system_u:object_r:unlabeled_t:s15:c0.c1023 tclass=file permissive=1 trawcon=system_u:object_r:banana_t:s0 Note that it is also possible to encounter this situation with the 'scontext' field - e.g. when a new policy is loaded while a process is running, whose context is not valid in the new policy. Link: https://bugzilla.redhat.com/show_bug.cgi?id=1135683 Cc: Daniel Walsh <dwalsh@redhat.com> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-01-25selinux: replace some BUG_ON()s with a WARN_ON()Ondrej Mosnacek1-2/+3
We don't need to crash the machine in these cases. Let's just detect the buggy state early and error out with a warning. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-01-25selinux: inline some AVC functions used only onceOndrej Mosnacek1-82/+58
avc_dump_av() and avc_dump_query() are each used only in one place. Get rid of them and open code their contents in the call sites. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-01-10selinux: stop passing MAY_NOT_BLOCK to the AVC upon follow_linkStephen Smalley1-22/+2
commit bda0be7ad9948 ("security: make inode_follow_link RCU-walk aware") switched selinux_inode_follow_link() to use avc_has_perm_flags() and pass down the MAY_NOT_BLOCK flag if called during RCU walk. However, the only test of MAY_NOT_BLOCK occurs during slow_avc_audit() and only if passing an inode as audit data (LSM_AUDIT_DATA_INODE). Since selinux_inode_follow_link() passes a dentry directly, passing MAY_NOT_BLOCK here serves no purpose. Switch selinux_inode_follow_link() to use avc_has_perm() and drop avc_has_perm_flags() since there are no other users. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-01-10selinux: avoid silent denials in permissive mode under RCU walkStephen Smalley1-2/+21
commit 0dc1ba24f7fff6 ("SELINUX: Make selinux cache VFS RCU walks safe") results in no audit messages at all if in permissive mode because the cache is updated during the rcu walk and thus no denial occurs on the subsequent ref walk. Fix this by not updating the cache when performing a non-blocking permission check. This only affects search and symlink read checks during rcu walk. Fixes: 0dc1ba24f7fff6 ("SELINUX: Make selinux cache VFS RCU walks safe") Reported-by: BMK <bmktuwien@gmail.com> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-06-19selinux: Cleanup printk logging in avcpeter enderborg1-1/+1
Replace printk with pr_* to avoid checkpatch warnings. Signed-off-by: Peter Enderborg <peter.enderborg@sony.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-03-20selinux: wrap AVC stateStephen Smalley1-122/+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>
2018-03-02selinux: rename the {is,set}_enforcing() functionsPaul Moore1-1/+1
Rename is_enforcing() to enforcing_enabled() and enforcing_set() to set_enforcing(). Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-03-01selinux: wrap global selinux stateStephen Smalley1-6/+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>
2017-09-12Merge tag 'selinux-pr-20170831' of ↵Linus Torvalds1-9/+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.
2017-09-05selinux: remove AVC init audit log messageRichard Guy Briggs1-2/+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>
2017-08-17selinux: update my email addressStephen Smalley1-1/+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>
2017-08-08selinux: use GFP_NOWAIT in the AVC kmem_cachesMichal Hocko1-8/+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>
2015-08-15Merge branch 'next' of git://git.infradead.org/users/pcmoore/selinux into nextJames Morris1-16/+402
2015-07-13selinux: Augment BUG_ON assertion for secclass_map.Stephen Smalley1-1/+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>
2015-07-13selinux: extended permissions for ioctlsJeff Vander Stoep1-15/+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>
2015-05-11security/selinux: pass 'flags' arg to avc_audit() and avc_has_perm_flags()NeilBrown1-1/+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>
2015-04-06selinux: remove unnecessary pointer reassignmentJeff Vander Stoep1-4/+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>
2015-02-04selinux: Remove unused function avc_sidcmp()Rickard Strandqvist1-5/+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>
2014-06-03selinux: Report permissive mode in avc: denied messages.Stephen Smalley1-1/+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>
2013-10-04selinux: remove 'flags' parameter from avc_audit()Linus Torvalds1-1/+1
Now avc_audit() has no more users with that parameter. Remove it. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-04selinux: avc_has_perm_flags has no more usersLinus Torvalds1-6/+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>
2013-02-27hlist: drop the node parameter from iteratorsSasha Levin1-13/+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>
2012-07-31selinux: tag avc cache alloc as non-criticalMel Gorman1-1/+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>
2012-04-09SELinux: avc: remove the useless fields in avc_add_callbackWanlong Gao1-26/+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>
2012-04-09SELinux: replace weak GFP_ATOMIC to GFP_KERNEL in avc_add_callbackWanlong Gao1-2/+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>
2012-04-09SELinux: unify the selinux_audit_data and selinux_late_audit_dataEric Paris1-16/+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>
2012-04-09LSM: do not initialize common_audit_data to 0Eric Paris1-1/+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>
2012-04-09LSM: remove the COMMON_AUDIT_DATA_INIT type expansionEric Paris1-1/+1
Just open code it so grep on the source code works better. Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09SELinux: delay initialization of audit data in selinux_inode_permissionEric Paris1-62/+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>
2012-04-03lsm_audit: don't specify the audit pre/post callbacks in 'struct ↵Linus Torvalds1-3/+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>
2012-04-03SELinux: do not allocate stack space for AVC data unless neededEric Paris1-12/+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>
2012-04-03SELinux: remove avd from slow_avc_audit()Eric Paris1-2/+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>
2012-04-03LSM: shrink sizeof LSM specific portion of common_audit_dataEric Paris1-16/+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>
2012-03-31selinux: inline avc_audit() and avc_has_perm_noaudit() into callerLinus Torvalds1-2/+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>
2012-03-31selinux: don't inline slow-path code into avc_has_perm_noaudit()Linus Torvalds1-14/+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>
2012-03-22security: optimize avc_audit() common pathLinus Torvalds1-29/+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>
2011-07-20selinux: don't transliterate MAY_NOT_BLOCK to IPERM_FLAG_RCUAl Viro1-1/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-26selinux: don't pass in NULL avd to avc_has_perm_noauditLinus Torvalds1-10/+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>
2011-05-24Merge branch 'master' of git://git.infradead.org/users/eparis/selinux into ↵James Morris1-1/+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>
2011-05-19selinux: avoid unnecessary avc cache stat hit countLinus Torvalds1-5/+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>
2011-05-19selinux: de-crapify avc cache stat code generationLinus Torvalds1-5/+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>
2011-04-25SELINUX: Make selinux cache VFS RCU walks safeEric Paris1-7/+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>
2011-04-25LSM: split LSM_AUDIT_DATA_FS into _PATH and _INODEEric Paris1-1/+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>
2011-04-25SELINUX: Make selinux cache VFS RCU walks safeEric Paris1-7/+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>
2010-08-02SELinux: special dontaudit for access checksEric Paris1-2/+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>
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