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* Merge tag 'selinux-pr-20240911' of ↵Linus Torvalds2024-09-161-14/+6
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: - Ensure that both IPv4 and IPv6 connections are properly initialized While we always properly initialized IPv4 connections early in their life, we missed the necessary IPv6 change when we were adding IPv6 support. - Annotate the SELinux inode revalidation function to quiet KCSAN KCSAN correctly identifies a race in __inode_security_revalidate() when we check to see if an inode's SELinux has been properly initialized. While KCSAN is correct, it is an intentional choice made for performance reasons; if necessary, we check the state a second time, this time with a lock held, before initializing the inode's state. - Code cleanups, simplification, etc. A handful of individual patches to simplify some SELinux kernel logic, improve return code granularity via ERR_PTR(), follow the guidance on using KMEM_CACHE(), and correct some minor style problems. * tag 'selinux-pr-20240911' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: fix style problems in security/selinux/include/audit.h selinux: simplify avc_xperms_audit_required() selinux: mark both IPv4 and IPv6 accepted connection sockets as labeled selinux: replace kmem_cache_create() with KMEM_CACHE() selinux: annotate false positive data race to avoid KCSAN warnings selinux: refactor code to return ERR_PTR in selinux_netlbl_sock_genattr selinux: Streamline type determination in security_compute_sid
| * selinux: simplify avc_xperms_audit_required()Zhen Lei2024-08-281-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | By associative and commutative laws, the result of the two 'audited' is zero. Take the second 'audited' as an example: 1) audited = requested & avd->auditallow; 2) audited &= ~requested; ==> audited = ~requested & (requested & avd->auditallow); ==> audited = (~requested & requested) & avd->auditallow; ==> audited = 0 & avd->auditallow; ==> audited = 0; In fact, it is more readable to directly write zero. The value of the first 'audited' is 0 because AUDIT is not allowed. The second 'audited' is zero because there is no AUDITALLOW permission. Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
| * selinux: replace kmem_cache_create() with KMEM_CACHE()Eric Suen2024-08-271-12/+4
| | | | | | | | | | | | | | | | | | | | Based on guidance in include/linux/slab.h, replace kmem_cache_create() with KMEM_CACHE() for sources under security/selinux to simplify creation of SLAB caches. Signed-off-by: Eric Suen <ericsu@linux.microsoft.com> [PM: minor grammar nits in the description] Signed-off-by: Paul Moore <paul@paul-moore.com>
* | selinux: add the processing of the failure of avc_add_xperms_decision()Zhen Lei2024-08-071-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | When avc_add_xperms_decision() fails, the information recorded by the new avc node is incomplete. In this case, the new avc node should be released instead of replacing the old avc node. Cc: stable@vger.kernel.org Fixes: fa1aa143ac4a ("selinux: extended permissions for ioctls") Suggested-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* | selinux: fix potential counting error in avc_add_xperms_decision()Zhen Lei2024-08-061-1/+1
|/ | | | | | | | | | | The count increases only when a node is successfully added to the linked list. Cc: stable@vger.kernel.org Fixes: fa1aa143ac4a ("selinux: extended permissions for ioctls") Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: update my email addressStephen Smalley2023-07-191-1/+1
| | | | | | | Update my email address; MAINTAINERS was updated some time ago. Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: avoid implicit conversions in the AVC codeChristian Göttsche2023-07-181-7/+8
| | | | | | | | | | | Use a consistent type of u32 for sequence numbers. Use a non-negative and input parameter matching type for the hash result. Signed-off-by: Christian Göttsche <cgzones@googlemail.com> [PM: subject line tweaks] Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: drop return at end of void function avc_insert()Christian Göttsche2023-05-081-1/+0
| | | | | | | | | Commit 539813e4184a ("selinux: stop returning node from avc_insert()") converted the return value of avc_insert() to void but left the now unnecessary trailing return statement. Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: avc: drop unused function avc_disable()Christian Göttsche2023-05-081-19/+0
| | | | | | | | Since commit f22f9aaf6c3d ("selinux: remove the runtime disable functionality") the function avc_disable() is no longer used. Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: stop returning node from avc_insert()Stephen Smalley2023-04-041-13/+11
| | | | | | | | | | | | The callers haven't used the returned node since commit 21193dcd1f3570dd ("SELinux: more careful use of avd in avc_has_perm_noaudit") and the return value assignments were removed in commit 0a9876f36b08706d ("selinux: Remove redundant assignments"). Stop returning the node altogether and make the functions return void. Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com> PM: minor subj tweak, repair whitespace damage Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: stop passing selinux_state pointers and their offspringStephen Smalley2023-03-141-111/+86
| | | | | | | | | | | | | | | | | | | Linus observed that the pervasive passing of selinux_state pointers introduced by me in commit aa8e712cee93 ("selinux: wrap global selinux state") adds overhead and complexity without providing any benefit. The original idea was to pave the way for SELinux namespaces but those have not yet been implemented and there isn't currently a concrete plan to do so. Remove the passing of the selinux_state pointers, reverting to direct use of the single global selinux_state, and likewise remove passing of child pointers like the selinux_avc. The selinux_policy pointer remains as it is needed for atomic switching of policies. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/oe-kbuild-all/202303101057.mZ3Gv5fK-lkp@intel.com/ Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: uninline unlikely parts of avc_has_perm_noaudit()Paul Moore2023-03-081-28/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is based on earlier patch posted to the list by Linus, his commit description read: "avc_has_perm_noaudit()is one of those hot functions that end up being used by almost all filesystem operations (through "avc_has_perm()") and it's intended to be cheap enough to inline. However, it turns out that the unlikely parts of it (where it doesn't find an existing avc node) need a fair amount of stack space for the automatic replacement node, so if it were to be inlined (at least clang does not) it would just use stack space unnecessarily. So split the unlikely part out of it, and mark that part noinline. That improves the actual likely part." The basic idea behind the patch was reasonable, but there were minor nits (double indenting, etc.) and the RCU read lock unlock/re-lock in avc_compute_av() began to look even more ugly. This patch builds on Linus' first effort by cleaning things up a bit and removing the RCU unlock/lock dance in avc_compute_av(). Removing the RCU lock dance in avc_compute_av() is safe as there are currently two callers of avc_compute_av(): avc_has_perm_noaudit() and avc_has_extended_perms(). The first caller in avc_has_perm_noaudit() does not require a RCU lock as there is no avc_node to protect so the RCU lock can be dropped before calling avc_compute_av(). The second caller, avc_has_extended_perms(), is similar in that there is no avc_node that requires RCU protection, but the code is simplified by holding the RCU look around the avc_compute_av() call, and given that we enter a RCU critical section in security_compute_av() (called from av_compute_av()) the impact will likely be unnoticeable. It is also worth noting that avc_has_extended_perms() is only called from the SELinux ioctl() access control hook at the moment. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: declare data arrays constChristian Göttsche2022-05-031-1/+1
| | | | | | | | | | | | | | | | The arrays for the policy capability names, the initial sid identifiers and the class and permission names are not changed at runtime. Declare them const to avoid accidental modification. Do not override the classmap and the initial sid list in the build time script genheaders. Check flose(3) is successful in genheaders.c, otherwise the written data might be corrupted or incomplete. Signed-off-by: Christian Göttsche <cgzones@googlemail.com> [PM: manual merge due to fuzz, minor style tweaks] Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: Remove redundant assignmentsMichal Orzel2022-04-041-2/+2
| | | | | | | | | | Get rid of redundant assignments which end up in values not being read either because they are overwritten or the function ends. Reported by clang-tidy [deadcode.DeadStores] Signed-off-by: Michal Orzel <michalorzel.eng@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: fix all of the W=1 build warningsPaul Moore2021-10-131-1/+12
| | | | | | | | | | | | | There were a number of places in the code where the function definition did not match the associated comment block as well at least one file where the appropriate header files were not included (missing function declaration/prototype); this patch fixes all of these issue such that building the SELinux code with "W=1" is now warning free. % make W=1 security/selinux/ Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: kill 'flags' argument in avc_has_perm_flags() and avc_audit()Al Viro2021-06-111-19/+1
| | | | | | | | | ... along with avc_has_perm_flags() itself, since now it's identical to avc_has_perm() (as pointed out by Paul Moore) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> [PM: add "selinux:" prefix to subj and tweak for length] Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: slow_avc_audit has become non-blockingAl Viro2021-06-111-20/+8
| | | | | | | | dump_common_audit_data() is safe to use under rcu_read_lock() now; no need for AVC_NONBLOCKING and games around it Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: use __GFP_NOWARN with GFP_NOWAIT in the AVCMinchan Kim2021-06-101-6/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the field, we have seen lots of allocation failure from the call path below. 06-03 13:29:12.999 1010315 31557 31557 W Binder : 31542_2: page allocation failure: order:0, mode:0x800(GFP_NOWAIT), nodemask=(null),cpuset=background,mems_allowed=0 ... ... 06-03 13:29:12.999 1010315 31557 31557 W Call trace: 06-03 13:29:12.999 1010315 31557 31557 W : dump_backtrace.cfi_jt+0x0/0x8 06-03 13:29:12.999 1010315 31557 31557 W : dump_stack+0xc8/0x14c 06-03 13:29:12.999 1010315 31557 31557 W : warn_alloc+0x158/0x1c8 06-03 13:29:12.999 1010315 31557 31557 W : __alloc_pages_slowpath+0x9d8/0xb80 06-03 13:29:12.999 1010315 31557 31557 W : __alloc_pages_nodemask+0x1c4/0x430 06-03 13:29:12.999 1010315 31557 31557 W : allocate_slab+0xb4/0x390 06-03 13:29:12.999 1010315 31557 31557 W : ___slab_alloc+0x12c/0x3a4 06-03 13:29:12.999 1010315 31557 31557 W : kmem_cache_alloc+0x358/0x5e4 06-03 13:29:12.999 1010315 31557 31557 W : avc_alloc_node+0x30/0x184 06-03 13:29:12.999 1010315 31557 31557 W : avc_update_node+0x54/0x4f0 06-03 13:29:12.999 1010315 31557 31557 W : avc_has_extended_perms+0x1a4/0x460 06-03 13:29:12.999 1010315 31557 31557 W : selinux_file_ioctl+0x320/0x3d0 06-03 13:29:12.999 1010315 31557 31557 W : __arm64_sys_ioctl+0xec/0x1fc 06-03 13:29:12.999 1010315 31557 31557 W : el0_svc_common+0xc0/0x24c 06-03 13:29:12.999 1010315 31557 31557 W : el0_svc+0x28/0x88 06-03 13:29:12.999 1010315 31557 31557 W : el0_sync_handler+0x8c/0xf0 06-03 13:29:12.999 1010315 31557 31557 W : el0_sync+0x1a4/0x1c0 .. .. 06-03 13:29:12.999 1010315 31557 31557 W SLUB : Unable to allocate memory on node -1, gfp=0x900(GFP_NOWAIT|__GFP_ZERO) 06-03 13:29:12.999 1010315 31557 31557 W cache : avc_node, object size: 72, buffer size: 80, default order: 0, min order: 0 06-03 13:29:12.999 1010315 31557 31557 W node 0 : slabs: 57, objs: 2907, free: 0 06-03 13:29:12.999 1010161 10686 10686 W SLUB : Unable to allocate memory on node -1, gfp=0x900(GFP_NOWAIT|__GFP_ZERO) 06-03 13:29:12.999 1010161 10686 10686 W cache : avc_node, object size: 72, buffer size: 80, default order: 0, min order: 0 06-03 13:29:12.999 1010161 10686 10686 W node 0 : slabs: 57, objs: 2907, free: 0 06-03 13:29:12.999 1010161 10686 10686 W SLUB : Unable to allocate memory on node -1, gfp=0x900(GFP_NOWAIT|__GFP_ZERO) 06-03 13:29:12.999 1010161 10686 10686 W cache : avc_node, object size: 72, buffer size: 80, default order: 0, min order: 0 06-03 13:29:12.999 1010161 10686 10686 W node 0 : slabs: 57, objs: 2907, free: 0 06-03 13:29:12.999 1010161 10686 10686 W SLUB : Unable to allocate memory on node -1, gfp=0x900(GFP_NOWAIT|__GFP_ZERO) 06-03 13:29:12.999 1010161 10686 10686 W cache : avc_node, object size: 72, buffer size: 80, default order: 0, min order: 0 06-03 13:29:12.999 1010161 10686 10686 W node 0 : slabs: 57, objs: 2907, free: 0 06-03 13:29:13.000 1010161 10686 10686 W SLUB : Unable to allocate memory on node -1, gfp=0x900(GFP_NOWAIT|__GFP_ZERO) 06-03 13:29:13.000 1010161 10686 10686 W cache : avc_node, object size: 72, buffer size: 80, default order: 0, min order: 0 06-03 13:29:13.000 1010161 10686 10686 W node 0 : slabs: 57, objs: 2907, free: 0 06-03 13:29:13.000 1010161 10686 10686 W SLUB : Unable to allocate memory on node -1, gfp=0x900(GFP_NOWAIT|__GFP_ZERO) 06-03 13:29:13.000 1010161 10686 10686 W cache : avc_node, object size: 72, buffer size: 80, default order: 0, min order: 0 06-03 13:29:13.000 1010161 10686 10686 W node 0 : slabs: 57, objs: 2907, free: 0 06-03 13:29:13.000 1010161 10686 10686 W SLUB : Unable to allocate memory on node -1, gfp=0x900(GFP_NOWAIT|__GFP_ZERO) 06-03 13:29:13.000 1010161 10686 10686 W cache : avc_node, object size: 72, buffer size: 80, default order: 0, min order: 0 06-03 13:29:13.000 1010161 10686 10686 W node 0 : slabs: 57, objs: 2907, free: 0 06-03 13:29:13.000 10230 30892 30892 W SLUB : Unable to allocate memory on node -1, gfp=0x900(GFP_NOWAIT|__GFP_ZERO) 06-03 13:29:13.000 10230 30892 30892 W cache : avc_node, object size: 72, buffer size: 80, default order: 0, min order: 0 06-03 13:29:13.000 10230 30892 30892 W node 0 : slabs: 57, objs: 2907, free: 0 06-03 13:29:13.000 10230 30892 30892 W SLUB : Unable to allocate memory on node -1, gfp=0x900(GFP_NOWAIT|__GFP_ZERO) 06-03 13:29:13.000 10230 30892 30892 W cache : avc_node, object size: 72, buffer size: 80, default order: 0, min order: 0 Based on [1], selinux is tolerate for failure of memory allocation. Then, use __GFP_NOWARN together. [1] 476accbe2f6e ("selinux: use GFP_NOWAIT in the AVC kmem_caches") Signed-off-by: Minchan Kim <minchan@kernel.org> [PM: subj fix, line wraps, normalized commit refs] Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: Corrected comment to match kernel-doc commentSouptick Joarder2021-05-101-1/+1
| | | | | | | | | Minor documentation update. Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Cc: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: mark some global variables __ro_after_initOndrej Mosnacek2021-01-121-5/+5
| | | | | | | | All of these are never modified outside initcalls, so they can be __ro_after_init. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: add basic filtering for audit trace eventsPeter Enderborg2020-08-211-13/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds further attributes to the event. These attributes are helpful to understand the context of the message and can be used to filter the events. There are three common items. Source context, target context and tclass. There are also items from the outcome of operation performed. An event is similar to: <...>-1309 [002] .... 6346.691689: selinux_audited: requested=0x4000000 denied=0x4000000 audited=0x4000000 result=-13 scontext=system_u:system_r:cupsd_t:s0-s0:c0.c1023 tcontext=system_u:object_r:bin_t:s0 tclass=file With systems where many denials are occurring, it is useful to apply a filter. The filtering is a set of logic that is inserted with the filter file. Example: echo "tclass==\"file\" " > events/avc/selinux_audited/filter This adds that we only get tclass=file. The trace can also have extra properties. Adding the user stack can be done with echo 1 > options/userstacktrace Now the output will be runcon-1365 [003] .... 6960.955530: selinux_audited: requested=0x4000000 denied=0x4000000 audited=0x4000000 result=-13 scontext=system_u:system_r:cupsd_t:s0-s0:c0.c1023 tcontext=system_u:object_r:bin_t:s0 tclass=file runcon-1365 [003] .... 6960.955560: <user stack trace> => <00007f325b4ce45b> => <00005607093efa57> Signed-off-by: Peter Enderborg <peter.enderborg@sony.com> Reviewed-by: Thiébaud Weksteen <tweek@google.com> Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: add tracepoint on audited eventsThiébaud Weksteen2020-08-211-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The audit data currently captures which process and which target is responsible for a denial. There is no data on where exactly in the process that call occurred. Debugging can be made easier by being able to reconstruct the unified kernel and userland stack traces [1]. Add a tracepoint on the SELinux denials which can then be used by userland (i.e. perf). Although this patch could manually be added by each OS developer to trouble shoot a denial, adding it to the kernel streamlines the developers workflow. It is possible to use perf for monitoring the event: # perf record -e avc:selinux_audited -g -a ^C # perf report -g [...] 6.40% 6.40% audited=800000 tclass=4 | __libc_start_main | |--4.60%--__GI___ioctl | entry_SYSCALL_64 | do_syscall_64 | __x64_sys_ioctl | ksys_ioctl | binder_ioctl | binder_set_nice | can_nice | capable | security_capable | cred_has_capability.isra.0 | slow_avc_audit | common_lsm_audit | avc_audit_post_callback | avc_audit_post_callback | It is also possible to use the ftrace interface: # echo 1 > /sys/kernel/debug/tracing/events/avc/selinux_audited/enable # cat /sys/kernel/debug/tracing/trace tracer: nop entries-in-buffer/entries-written: 1/1 #P:8 [...] dmesg-3624 [001] 13072.325358: selinux_denied: audited=800000 tclass=4 The tclass value can be mapped to a class by searching security/selinux/flask.h. The audited value is a bit field of the permissions described in security/selinux/av_permissions.h for the corresponding class. [1] https://source.android.com/devices/tech/debug/native_stack_dump Signed-off-by: Thiébaud Weksteen <tweek@google.com> Suggested-by: Joel Fernandes <joelaf@google.com> Reviewed-by: Peter Enderborg <peter.enderborg@sony.com> Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: ensure we cleanup the internal AVC counters on error in avc_update()Jaihind Yadav2019-12-211-1/+1
| | | | | | | | | | | | In AVC update we don't call avc_node_kill() when avc_xperms_populate() fails, resulting in the avc->avc_cache.active_nodes counter having a false value. In last patch this changes was missed , so correcting it. Fixes: fa1aa143ac4a ("selinux: extended permissions for ioctls") Signed-off-by: Jaihind Yadav <jaihindyadav@codeaurora.org> Signed-off-by: Ravi Kumar Siddojigari <rsiddoji@codeaurora.org> [PM: merge fuzz, minor description cleanup] Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: ensure we cleanup the internal AVC counters on error in avc_insert()Paul Moore2019-12-101-27/+24
| | | | | | | | | | | Fix avc_insert() to call avc_node_kill() if we've already allocated an AVC node and the code fails to insert the node in the cache. Fixes: fa1aa143ac4a ("selinux: extended permissions for ioctls") Reported-by: rsiddoji@codeaurora.org Suggested-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: fall back to ref-walk if audit is requiredStephen Smalley2019-12-091-19/+5
| | | | | | | | | | | | | | | | | commit bda0be7ad994 ("security: make inode_follow_link RCU-walk aware") passed down the rcu flag to the SELinux AVC, but failed to adjust the test in slow_avc_audit() to also return -ECHILD on LSM_AUDIT_DATA_DENTRY. Previously, we only returned -ECHILD if generating an audit record with LSM_AUDIT_DATA_INODE since this was only relevant from inode_permission. Move the handling of MAY_NOT_BLOCK to avc_audit() and its inlined equivalent in selinux_inode_permission() immediately after we determine that audit is required, and always fall back to ref-walk in this case. Fixes: bda0be7ad994 ("security: make inode_follow_link RCU-walk aware") Reported-by: Will Deacon <will@kernel.org> Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
* selinux: revert "stop passing MAY_NOT_BLOCK to the AVC upon follow_link"Stephen Smalley2019-12-091-2/+22
| | | | | | | | | | | | This reverts commit e46e01eebbbc ("selinux: stop passing MAY_NOT_BLOCK to the AVC upon follow_link"). The correct fix is to instead fall back to ref-walk if audit is required irrespective of the specific audit data type. This is done in the next commit. Fixes: e46e01eebbbc ("selinux: stop passing MAY_NOT_BLOCK to the AVC upon follow_link") Reported-by: Will Deacon <will@kernel.org> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner2019-06-191-4/+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>
* selinux: log raw contexts as untrusted stringsOndrej Mosnacek2019-06-111-2/+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>
* selinux: fix avc audit messagesStephen Smalley2019-02-051-3/+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>
* selinux: replace BUG_ONs with WARN_ONs in avc.cOndrej Mosnacek2019-01-281-2/+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>
* selinux: log invalid contexts in AVCsOndrej Mosnacek2019-01-251-0/+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>
* selinux: replace some BUG_ON()s with a WARN_ON()Ondrej Mosnacek2019-01-251-2/+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>
* selinux: inline some AVC functions used only onceOndrej Mosnacek2019-01-251-82/+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>
* selinux: stop passing MAY_NOT_BLOCK to the AVC upon follow_linkStephen Smalley2019-01-101-22/+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>
* selinux: avoid silent denials in permissive mode under RCU walkStephen Smalley2019-01-101-2/+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>
* selinux: Cleanup printk logging in avcpeter enderborg2018-06-191-1/+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>
* 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 Smalley2018-03-011-6/+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 Stoep2015-04-061-4/+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>