aboutsummaryrefslogtreecommitdiff
path: root/security/selinux/include/objsec.h
AgeCommit message (Collapse)Author
2021-04-22LSM: Infrastructure management of the superblockCasey Schaufler
Move management of the superblock->sb_security blob out of the individual security modules and into the security infrastructure. Instead of allocating the blobs from within the modules, the modules tell the infrastructure how much space is required, and the space is allocated there. Cc: John Johansen <john.johansen@canonical.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com> Reviewed-by: Stephen Smalley <stephen.smalley.work@gmail.com> Acked-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210422154123.13086-6-mic@digikod.net Signed-off-by: James Morris <jamorris@linux.microsoft.com>
2020-11-12selinux: drop super_block backpointer from superblock_security_structOndrej Mosnacek
It appears to have been needed for selinux_complete_init() in the past, but today it's useless. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-12-18selinux: randomize layout of key structuresStephen Smalley
Randomize the layout of key selinux data structures. Initially this is applied to the selinux_state, selinux_ss, policydb, and task_security_struct data structures. NB To test/use this mechanism, one must install the necessary build-time dependencies, e.g. gcc-plugin-devel on Fedora, and enable CONFIG_GCC_PLUGIN_RANDSTRUCT in the kernel configuration. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Reviewed-by: Kees Cook <keescook@chromium.org> [PM: double semi-colon fixed] Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-10-17perf_event: Add support for LSM and SELinux checksJoel Fernandes (Google)
In current mainline, the degree of access to perf_event_open(2) system call depends on the perf_event_paranoid sysctl. This has a number of limitations: 1. The sysctl is only a single value. Many types of accesses are controlled based on the single value thus making the control very limited and coarse grained. 2. The sysctl is global, so if the sysctl is changed, then that means all processes get access to perf_event_open(2) opening the door to security issues. This patch adds LSM and SELinux access checking which will be used in Android to access perf_event_open(2) for the purposes of attaching BPF programs to tracepoints, perf profiling and other operations from userspace. These operations are intended for production systems. 5 new LSM hooks are added: 1. perf_event_open: This controls access during the perf_event_open(2) syscall itself. The hook is called from all the places that the perf_event_paranoid sysctl is checked to keep it consistent with the systctl. The hook gets passed a 'type' argument which controls CPU, kernel and tracepoint accesses (in this context, CPU, kernel and tracepoint have the same semantics as the perf_event_paranoid sysctl). Additionally, I added an 'open' type which is similar to perf_event_paranoid sysctl == 3 patch carried in Android and several other distros but was rejected in mainline [1] in 2016. 2. perf_event_alloc: This allocates a new security object for the event which stores the current SID within the event. It will be useful when the perf event's FD is passed through IPC to another process which may try to read the FD. Appropriate security checks will limit access. 3. perf_event_free: Called when the event is closed. 4. perf_event_read: Called from the read(2) and mmap(2) syscalls for the event. 5. perf_event_write: Called from the ioctl(2) syscalls for the event. [1] https://lwn.net/Articles/696240/ Since Peter had suggest LSM hooks in 2016 [1], I am adding his Suggested-by tag below. To use this patch, we set the perf_event_paranoid sysctl to -1 and then apply selinux checking as appropriate (default deny everything, and then add policy rules to give access to domains that need it). In the future we can remove the perf_event_paranoid sysctl altogether. Suggested-by: Peter Zijlstra <peterz@infradead.org> Co-developed-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: James Morris <jmorris@namei.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: rostedt@goodmis.org Cc: Yonghong Song <yhs@fb.com> Cc: Kees Cook <keescook@chromium.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: jeffv@google.com Cc: Jiri Olsa <jolsa@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: primiano@google.com Cc: Song Liu <songliubraving@fb.com> Cc: rsavitski@google.com Cc: Namhyung Kim <namhyung@kernel.org> Cc: Matthew Garrett <matthewgarrett@google.com> Link: https://lkml.kernel.org/r/20191014170308.70668-1-joel@joelfernandes.org
2019-09-23Merge tag 'selinux-pr-20190917' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: - Add LSM hooks, and SELinux access control hooks, for dnotify, fanotify, and inotify watches. This has been discussed with both the LSM and fs/notify folks and everybody is good with these new hooks. - The LSM stacking changes missed a few calls to current_security() in the SELinux code; we fix those and remove current_security() for good. - Improve our network object labeling cache so that we always return the object's label, even when under memory pressure. Previously we would return an error if we couldn't allocate a new cache entry, now we always return the label even if we can't create a new cache entry for it. - Convert the sidtab atomic_t counter to a normal u32 with READ/WRITE_ONCE() and memory barrier protection. - A few patches to policydb.c to clean things up (remove forward declarations, long lines, bad variable names, etc) * tag 'selinux-pr-20190917' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: lsm: remove current_security() selinux: fix residual uses of current_security() for the SELinux blob selinux: avoid atomic_t usage in sidtab fanotify, inotify, dnotify, security: add security hook for fs notifications selinux: always return a secid from the network caches if we find one selinux: policydb - rename type_val_to_struct_array selinux: policydb - fix some checkpatch.pl warnings selinux: shuffle around policydb.c to get rid of forward declarations
2019-09-04selinux: fix residual uses of current_security() for the SELinux blobStephen Smalley
We need to use selinux_cred() to fetch the SELinux cred blob instead of directly using current->security or current_security(). There were a couple of lingering uses of current_security() in the SELinux code that were apparently missed during the earlier conversions. IIUC, this would only manifest as a bug if multiple security modules including SELinux are enabled and SELinux is not first in the lsm order. After this change, there appear to be no other users of current_security() in-tree; perhaps we should remove it altogether. Fixes: bbd3662a8348 ("Infrastructure management of the cred security blob") Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner
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>
2019-01-08LSM: Infrastructure management of the ipc security blobCasey Schaufler
Move management of the kern_ipc_perm->security and msg_msg->security blobs out of the individual security modules and into the security infrastructure. Instead of allocating the blobs from within the modules the modules tell the infrastructure how much space is required, and the space is allocated there. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> [kees: adjusted for ordered init series] Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-08SELinux: Abstract use of ipc security blobsCasey Schaufler
Don't use the ipc->security pointer directly. Don't use the msg_msg->security pointer directly. Provide helper functions that provides the security blob pointers. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-08LSM: Infrastructure management of the inode securityCasey Schaufler
Move management of the inode->i_security blob out of the individual security modules and into the security infrastructure. Instead of allocating the blobs from within the modules the modules tell the infrastructure how much space is required, and the space is allocated there. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> [kees: adjusted for ordered init series] Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-08SELinux: Abstract use of inode security blobCasey Schaufler
Don't use the inode->i_security pointer directly. Provide a helper function that provides the security blob pointer. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-08LSM: Infrastructure management of the file securityCasey Schaufler
Move management of the file->f_security blob out of the individual security modules and into the infrastructure. The modules no longer allocate or free the data, instead they tell the infrastructure how much space they require. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> [kees: adjusted for ordered init series] Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-08SELinux: Abstract use of file security blobCasey Schaufler
Don't use the file->f_security pointer directly. Provide a helper function that provides the security blob pointer. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-08Infrastructure management of the cred security blobCasey Schaufler
Move management of the cred security blob out of the security modules and into the security infrastructre. Instead of allocating and freeing space the security modules tell the infrastructure how much space they require. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> [kees: adjusted for ordered init series] Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-08SELinux: Abstract use of cred security blobCasey Schaufler
Don't use the cred->security pointer directly. Provide a helper function that provides the security blob pointer. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> [kees: adjusted for ordered init series] Signed-off-by: Kees Cook <keescook@chromium.org>
2018-03-01selinux: wrap global selinux stateStephen Smalley
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>
2018-02-26selinux: Add SCTP supportRichard Haines
The SELinux SCTP implementation is explained in: Documentation/security/SELinux-sctp.rst Signed-off-by: Richard Haines <richard_c_haines@btinternet.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-10-20selinux: bpf: Add selinux check for eBPF syscall operationsChenbo Feng
Implement the actual checks introduced to eBPF related syscalls. This implementation use the security field inside bpf object to store a sid that identify the bpf object. And when processes try to access the object, selinux will check if processes have the right privileges. The creation of eBPF object are also checked at the general bpf check hook and new cmd introduced to eBPF domain can also be checked there. Signed-off-by: Chenbo Feng <fengc@google.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-17selinux: update my email addressStephen Smalley
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>
2017-05-23selinux: Add a cache for quicker retreival of PKey SIDsDaniel Jurgens
It is likely that the SID for the same PKey will be requested many times. To reduce the time to modify QPs and process MADs use a cache to store PKey SIDs. This code is heavily based on the "netif" and "netport" concept originally developed by James Morris <jmorris@redhat.com> and Paul Moore <paul@paul-moore.com> (see security/selinux/netif.c and security/selinux/netport.c for more information) Signed-off-by: Daniel Jurgens <danielj@mellanox.com> Acked-by: Doug Ledford <dledford@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-05-23selinux: Allocate and free infiniband security hooksDaniel Jurgens
Implement and attach hooks to allocate and free Infiniband object security structures. Signed-off-by: Daniel Jurgens <danielj@mellanox.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Acked-by: Doug Ledford <dledford@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-01-09selinux: clean up cred usage and simplifyStephen Smalley
SELinux was sometimes using the task "objective" credentials when it could/should use the "subjective" credentials. This was sometimes hidden by the fact that we were unnecessarily passing around pointers to the current task, making it appear as if the task could be something other than current, so eliminate all such passing of current. Inline various permission checking helper functions that can be reduced to a single avc_has_perm() call. Since the credentials infrastructure only allows a task to alter its own credentials, we can always assume that current must be the same as the target task in selinux_setprocattr after the check. We likely should move this check from selinux_setprocattr() to proc_pid_attr_write() and drop the task argument to the security hook altogether; it can only serve to confuse things. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-11-22selinux: Convert isec->lock into a spinlockAndreas Gruenbacher
Convert isec->lock from a mutex into a spinlock. Instead of holding the lock while sleeping in inode_doinit_with_dentry, set isec->initialized to LABEL_PENDING and release the lock. Then, when the sid has been determined, re-acquire the lock. If isec->initialized is still set to LABEL_PENDING, set isec->sid; otherwise, the sid has been set by another task (LABEL_INITIALIZED) or invalidated (LABEL_INVALID) in the meantime. This fixes a deadlock on gfs2 where * one task is in inode_doinit_with_dentry -> gfs2_getxattr, holds isec->lock, and tries to acquire the inode's glock, and * another task is in do_xmote -> inode_go_inval -> selinux_inode_invalidate_secctx, holds the inode's glock, and tries to acquire isec->lock. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> [PM: minor tweaks to keep checkpatch.pl happy] Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-04-05selinux: simply inode label states to INVALID and INITIALIZEDPaul Moore
There really is no need for LABEL_MISSING as we really only care if the inode's label is INVALID or INITIALIZED. Also adjust the revalidate code to reload the label whenever the label is not INITIALIZED so we are less sensitive to label state in the future. Signed-off-by: Paul Moore <paul@paul-moore.com>
2015-12-24security: Add hook to invalidate inode security labelsAndreas Gruenbacher
Add a hook to invalidate an inode's security label when the cached information becomes invalid. Add the new hook in selinux: set a flag when a security label becomes invalid. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <pmoore@redhat.com>
2014-09-10selinux: make the netif cache namespace awarePaul Moore
While SELinux largely ignores namespaces, for good reason, there are some places where it needs to at least be aware of namespaces in order to function correctly. Network namespaces are one example. Basic awareness of network namespaces are necessary in order to match a network interface's index number to an actual network device. This patch corrects a problem with network interfaces added to a non-init namespace, and can be reproduced with the following commands: [NOTE: the NetLabel configuration is here only to active the dynamic networking controls ] # netlabelctl unlbl add default address:0.0.0.0/0 \ label:system_u:object_r:unlabeled_t:s0 # netlabelctl unlbl add default address:::/0 \ label:system_u:object_r:unlabeled_t:s0 # netlabelctl cipsov4 add pass doi:100 tags:1 # netlabelctl map add domain:lspp_test_netlabel_t \ protocol:cipsov4,100 # ip link add type veth # ip netns add myns # ip link set veth1 netns myns # ip a add dev veth0 10.250.13.100/24 # ip netns exec myns ip a add dev veth1 10.250.13.101/24 # ip l set veth0 up # ip netns exec myns ip l set veth1 up # ping -c 1 10.250.13.101 # ip netns exec myns ping -c 1 10.250.13.100 Reported-by: Jiri Jaburek <jjaburek@redhat.com> Signed-off-by: Paul Moore <pmoore@redhat.com>
2014-01-12SELinux: Fix possible NULL pointer dereference in selinux_inode_permission()Steven Rostedt
While running stress tests on adding and deleting ftrace instances I hit this bug: BUG: unable to handle kernel NULL pointer dereference at 0000000000000020 IP: selinux_inode_permission+0x85/0x160 PGD 63681067 PUD 7ddbe067 PMD 0 Oops: 0000 [#1] PREEMPT CPU: 0 PID: 5634 Comm: ftrace-test-mki Not tainted 3.13.0-rc4-test-00033-gd2a6dde-dirty #20 Hardware name: /DG965MQ, BIOS MQ96510J.86A.0372.2006.0605.1717 06/05/2006 task: ffff880078375800 ti: ffff88007ddb0000 task.ti: ffff88007ddb0000 RIP: 0010:[<ffffffff812d8bc5>] [<ffffffff812d8bc5>] selinux_inode_permission+0x85/0x160 RSP: 0018:ffff88007ddb1c48 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000800000 RCX: ffff88006dd43840 RDX: 0000000000000001 RSI: 0000000000000081 RDI: ffff88006ee46000 RBP: ffff88007ddb1c88 R08: 0000000000000000 R09: ffff88007ddb1c54 R10: 6e6576652f6f6f66 R11: 0000000000000003 R12: 0000000000000000 R13: 0000000000000081 R14: ffff88006ee46000 R15: 0000000000000000 FS: 00007f217b5b6700(0000) GS:ffffffff81e21000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033^M CR2: 0000000000000020 CR3: 000000006a0fe000 CR4: 00000000000007f0 Call Trace: security_inode_permission+0x1c/0x30 __inode_permission+0x41/0xa0 inode_permission+0x18/0x50 link_path_walk+0x66/0x920 path_openat+0xa6/0x6c0 do_filp_open+0x43/0xa0 do_sys_open+0x146/0x240 SyS_open+0x1e/0x20 system_call_fastpath+0x16/0x1b Code: 84 a1 00 00 00 81 e3 00 20 00 00 89 d8 83 c8 02 40 f6 c6 04 0f 45 d8 40 f6 c6 08 74 71 80 cf 02 49 8b 46 38 4c 8d 4d cc 45 31 c0 <0f> b7 50 20 8b 70 1c 48 8b 41 70 89 d9 8b 78 04 e8 36 cf ff ff RIP selinux_inode_permission+0x85/0x160 CR2: 0000000000000020 Investigating, I found that the inode->i_security was NULL, and the dereference of it caused the oops. in selinux_inode_permission(): isec = inode->i_security; rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); Note, the crash came from stressing the deletion and reading of debugfs files. I was not able to recreate this via normal files. But I'm not sure they are safe. It may just be that the race window is much harder to hit. What seems to have happened (and what I have traced), is the file is being opened at the same time the file or directory is being deleted. As the dentry and inode locks are not held during the path walk, nor is the inodes ref counts being incremented, there is nothing saving these structures from being discarded except for an rcu_read_lock(). The rcu_read_lock() protects against freeing of the inode, but it does not protect freeing of the inode_security_struct. Now if the freeing of the i_security happens with a call_rcu(), and the i_security field of the inode is not changed (it gets freed as the inode gets freed) then there will be no issue here. (Linus Torvalds suggested not setting the field to NULL such that we do not need to check if it is NULL in the permission check). Note, this is a hack, but it fixes the problem at hand. A real fix is to restructure the destroy_inode() to call all the destructor handlers from the RCU callback. But that is a major job to do, and requires a lot of work. For now, we just band-aid this bug with this fix (it works), and work on a more maintainable solution in the future. Link: http://lkml.kernel.org/r/20140109101932.0508dec7@gandalf.local.home Link: http://lkml.kernel.org/r/20140109182756.17abaaa8@gandalf.local.home Cc: stable@vger.kernel.org Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-25SELinux: change sbsec->behavior to shortEric Paris
We only have 6 options, so char is good enough, but use a short as that packs nicely. This shrinks the superblock_security_struct just a little bit. Signed-off-by: Eric Paris <eparis@redhat.com>
2013-07-25SELinux: renumber the superblock optionsEric Paris
Just to make it clear that we have mount time options and flags, separate them. Since I decided to move the non-mount options above above 0x10, we need a short instead of a char. (x86 padding says this takes up no additional space as we have a 3byte whole in the structure) Signed-off-by: Eric Paris <eparis@redhat.com>
2013-01-14tun: fix LSM/SELinux labeling of tun/tap devicesPaul Moore
This patch corrects some problems with LSM/SELinux that were introduced with the multiqueue patchset. The problem stems from the fact that the multiqueue work changed the relationship between the tun device and its associated socket; before the socket persisted for the life of the device, however after the multiqueue changes the socket only persisted for the life of the userspace connection (fd open). For non-persistent devices this is not an issue, but for persistent devices this can cause the tun device to lose its SELinux label. We correct this problem by adding an opaque LSM security blob to the tun device struct which allows us to have the LSM security state, e.g. SELinux labeling information, persist for the lifetime of the tun device. In the process we tweak the LSM hooks to work with this new approach to TUN device/socket labeling and introduce a new LSM hook, security_tun_dev_attach_queue(), to approve requests to attach to a TUN queue via TUNSETQUEUE. The SELinux code has been adjusted to match the new LSM hooks, the other LSMs do not make use of the LSM TUN controls. This patch makes use of the recently added "tun_socket:attach_queue" permission to restrict access to the TUNSETQUEUE operation. On older SELinux policies which do not define the "tun_socket:attach_queue" permission the access control decision for TUNSETQUEUE will be handled according to the SELinux policy's unknown permission setting. Signed-off-by: Paul Moore <pmoore@redhat.com> Acked-by: Eric Paris <eparis@parisplace.org> Tested-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-21switch selinux delayed superblock handling to iterate_supers()Al Viro
... kill their private list, while we are at it Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-19SELinux: Condense super block security structure flags and cleanup necessary ↵David P. Quigley
code. The super block security structure currently has three fields for what are essentially flags. The flags field is used for mount options while two other char fields are used for initialization and proc flags. These latter two fields are essentially bit fields since the only used values are 0 and 1. These fields have been collapsed into the flags field and new bit masks have been added for them. The code is also fixed to work with these new flags. Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@macbook.localdomain>
2008-11-14CRED: Make execve() take advantage of copy-on-write credentialsDavid Howells
Make execve() take advantage of copy-on-write credentials, allowing it to set up the credentials in advance, and then commit the whole lot after the point of no return. This patch and the preceding patches have been tested with the LTP SELinux testsuite. This patch makes several logical sets of alteration: (1) execve(). The credential bits from struct linux_binprm are, for the most part, replaced with a single credentials pointer (bprm->cred). This means that all the creds can be calculated in advance and then applied at the point of no return with no possibility of failure. I would like to replace bprm->cap_effective with: cap_isclear(bprm->cap_effective) but this seems impossible due to special behaviour for processes of pid 1 (they always retain their parent's capability masks where normally they'd be changed - see cap_bprm_set_creds()). The following sequence of events now happens: (a) At the start of do_execve, the current task's cred_exec_mutex is locked to prevent PTRACE_ATTACH from obsoleting the calculation of creds that we make. (a) prepare_exec_creds() is then called to make a copy of the current task's credentials and prepare it. This copy is then assigned to bprm->cred. This renders security_bprm_alloc() and security_bprm_free() unnecessary, and so they've been removed. (b) The determination of unsafe execution is now performed immediately after (a) rather than later on in the code. The result is stored in bprm->unsafe for future reference. (c) prepare_binprm() is called, possibly multiple times. (i) This applies the result of set[ug]id binaries to the new creds attached to bprm->cred. Personality bit clearance is recorded, but now deferred on the basis that the exec procedure may yet fail. (ii) This then calls the new security_bprm_set_creds(). This should calculate the new LSM and capability credentials into *bprm->cred. This folds together security_bprm_set() and parts of security_bprm_apply_creds() (these two have been removed). Anything that might fail must be done at this point. (iii) bprm->cred_prepared is set to 1. bprm->cred_prepared is 0 on the first pass of the security calculations, and 1 on all subsequent passes. This allows SELinux in (ii) to base its calculations only on the initial script and not on the interpreter. (d) flush_old_exec() is called to commit the task to execution. This performs the following steps with regard to credentials: (i) Clear pdeath_signal and set dumpable on certain circumstances that may not be covered by commit_creds(). (ii) Clear any bits in current->personality that were deferred from (c.i). (e) install_exec_creds() [compute_creds() as was] is called to install the new credentials. This performs the following steps with regard to credentials: (i) Calls security_bprm_committing_creds() to apply any security requirements, such as flushing unauthorised files in SELinux, that must be done before the credentials are changed. This is made up of bits of security_bprm_apply_creds() and security_bprm_post_apply_creds(), both of which have been removed. This function is not allowed to fail; anything that might fail must have been done in (c.ii). (ii) Calls commit_creds() to apply the new credentials in a single assignment (more or less). Possibly pdeath_signal and dumpable should be part of struct creds. (iii) Unlocks the task's cred_replace_mutex, thus allowing PTRACE_ATTACH to take place. (iv) Clears The bprm->cred pointer as the credentials it was holding are now immutable. (v) Calls security_bprm_committed_creds() to apply any security alterations that must be done after the creds have been changed. SELinux uses this to flush signals and signal handlers. (f) If an error occurs before (d.i), bprm_free() will call abort_creds() to destroy the proposed new credentials and will then unlock cred_replace_mutex. No changes to the credentials will have been made. (2) LSM interface. A number of functions have been changed, added or removed: (*) security_bprm_alloc(), ->bprm_alloc_security() (*) security_bprm_free(), ->bprm_free_security() Removed in favour of preparing new credentials and modifying those. (*) security_bprm_apply_creds(), ->bprm_apply_creds() (*) security_bprm_post_apply_creds(), ->bprm_post_apply_creds() Removed; split between security_bprm_set_creds(), security_bprm_committing_creds() and security_bprm_committed_creds(). (*) security_bprm_set(), ->bprm_set_security() Removed; folded into security_bprm_set_creds(). (*) security_bprm_set_creds(), ->bprm_set_creds() New. The new credentials in bprm->creds should be checked and set up as appropriate. bprm->cred_prepared is 0 on the first call, 1 on the second and subsequent calls. (*) security_bprm_committing_creds(), ->bprm_committing_creds() (*) security_bprm_committed_creds(), ->bprm_committed_creds() New. Apply the security effects of the new credentials. This includes closing unauthorised files in SELinux. This function may not fail. When the former is called, the creds haven't yet been applied to the process; when the latter is called, they have. The former may access bprm->cred, the latter may not. (3) SELinux. SELinux has a number of changes, in addition to those to support the LSM interface changes mentioned above: (a) The bprm_security_struct struct has been removed in favour of using the credentials-under-construction approach. (c) flush_unauthorized_files() now takes a cred pointer and passes it on to inode_has_perm(), file_has_perm() and dentry_open(). Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2008-10-10selinux: Cache NetLabel secattrs in the socket's security structPaul Moore
Previous work enabled the use of address based NetLabel selectors, which while highly useful, brought the potential for additional per-packet overhead when used. This patch attempts to mitigate some of that overhead by caching the NetLabel security attribute struct within the SELinux socket security structure. This should help eliminate the need to recreate the NetLabel secattr structure for each packet resulting in less overhead. Signed-off-by: Paul Moore <paul.moore@hp.com> Acked-by: James Morris <jmorris@namei.org>
2008-10-10selinux: Set socket NetLabel based on connection endpointPaul Moore
Previous work enabled the use of address based NetLabel selectors, which while highly useful, brought the potential for additional per-packet overhead when used. This patch attempts to solve that by applying NetLabel socket labels when sockets are connect()'d. This should alleviate the per-packet NetLabel labeling for all connected sockets (yes, it even works for connected DGRAM sockets). Signed-off-by: Paul Moore <paul.moore@hp.com> Reviewed-by: James Morris <jmorris@namei.org>
2008-10-10netlabel: Add functionality to set the security attributes of a packetPaul Moore
This patch builds upon the new NetLabel address selector functionality by providing the NetLabel KAPI and CIPSO engine support needed to enable the new packet-based labeling. The only new addition to the NetLabel KAPI at this point is shown below: * int netlbl_skbuff_setattr(skb, family, secattr) ... and is designed to be called from a Netfilter hook after the packet's IP header has been populated such as in the FORWARD or LOCAL_OUT hooks. This patch also provides the necessary SELinux hooks to support this new functionality. Smack support is not currently included due to uncertainty regarding the permissions needed to expand the Smack network access controls. Signed-off-by: Paul Moore <paul.moore@hp.com> Reviewed-by: James Morris <jmorris@namei.org>
2008-07-14SELinux: remove inherit field from inode_security_structJames Morris
Remove inherit field from inode_security_struct, per Stephen Smalley: "Let's just drop inherit altogether - dead field." Signed-off-by: James Morris <jmorris@namei.org>
2008-07-14SELinux: reorder inode_security_struct to increase objs/slab on 64bitRichard Kennedy
reorder inode_security_struct to remove padding on 64 bit builds size reduced from 72 to 64 bytes increasing objects per slab to 64. Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> Signed-off-by: James Morris <jmorris@namei.org>
2008-04-28SELinux: objsec.h whitespace, syntax, and other cleanupsEric Paris
This patch changes objsec.h to fix whitespace and syntax issues. Things that are fixed may include (does not not have to include) whitespace at end of lines spaces followed by tabs spaces used instead of tabs spacing around parenthesis location of { around structs and else clauses location of * in pointer declarations removal of initialization of static data to keep it in the right section useless {} in if statemetns useless checking for NULL before kfree fixing of the indentation depth of switch statements no assignments in if statements and any number of other things I forgot to mention Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2008-04-18SELinux: Add network port SID cachePaul Moore
Much like we added a network node cache, this patch adds a network port cache. The design is taken almost completely from the network node cache which in turn was taken from the network interface cache. The basic idea is to cache entries in a hash table based on protocol/port information. The hash function only takes the port number into account since the number of different protocols in use at any one time is expected to be relatively small. Signed-off-by: Paul Moore <paul.moore@hp.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2008-04-18selinux: remove ptrace_sidRoland McGrath
This changes checks related to ptrace to get rid of the ptrace_sid tracking. It's good to disentangle the security model from the ptrace implementation internals. It's sufficient to check against the SID of the ptracer at the time a tracee attempts a transition. Signed-off-by: Roland McGrath <roland@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2008-04-18SELinux: remove unused backpointers from security objectsJames Morris
Remove unused backpoiters from security objects. Signed-off-by: James Morris <jmorris@namei.org>
2008-04-18SELinux: Correct the NetLabel locking for the sk_security_structPaul Moore
The RCU/spinlock locking approach for the nlbl_state in the sk_security_struct was almost certainly overkill. This patch removes both the RCU and spinlock locking, relying on the existing socket locks to handle the case of multiple writers. This change also makes several code reductions possible. Less locking, less code - it's a Good Thing. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
2008-01-30SELinux: Better integration between peer labeling subsystemsPaul Moore
Rework the handling of network peer labels so that the different peer labeling subsystems work better together. This includes moving both subsystems to a single "peer" object class which involves not only changes to the permission checks but an improved method of consolidating multiple packet peer labels. As part of this work the inbound packet permission check code has been heavily modified to handle both the old and new behavior in as sane a fashion as possible. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
2008-01-30SELinux: Add a network node caching mechanism similar to the sel_netif_*() ↵Paul Moore
functions This patch adds a SELinux IP address/node SID caching mechanism similar to the sel_netif_*() functions. The node SID queries in the SELinux hooks files are also modified to take advantage of this new functionality. In addition, remove the address length information from the sk_buff parsing routines as it is redundant since we already have the address family. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
2008-01-30SELinux: Convert the netif code to use ifindex valuesPaul Moore
The current SELinux netif code requires the caller have a valid net_device struct pointer to lookup network interface information. However, we don't always have a valid net_device pointer so convert the netif code to use the ifindex values we always have as part of the sk_buff. This patch also removes the default message SID from the network interface record, it is not being used and therefore is "dead code". Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
2008-01-25Security: add get, set, and cloning of superblock security informationEric Paris
Adds security_get_sb_mnt_opts, security_set_sb_mnt_opts, and security_clont_sb_mnt_opts to the LSM and to SELinux. This will allow filesystems to directly own and control all of their mount options if they so choose. This interface deals only with option identifiers and strings so it should generic enough for any LSM which may come in the future. Filesystems which pass text mount data around in the kernel (almost all of them) need not currently make use of this interface when dealing with SELinux since it will still parse those strings as it always has. I assume future LSM's would do the same. NFS is the primary FS which does not use text mount data and thus must make use of this interface. An LSM would need to implement these functions only if they had mount time options, such as selinux has context= or fscontext=. If the LSM has no mount time options they could simply not implement and let the dummy ops take care of things. An LSM other than SELinux would need to define new option numbers in security.h and any FS which decides to own there own security options would need to be patched to use this new interface for every possible LSM. This is because it was stated to me very clearly that LSM's should not attempt to understand FS mount data and the burdon to understand security should be in the FS which owns the options. 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>
2007-10-17SELinux: Improve read/write performanceYuichi Nakamura
It reduces the selinux overhead on read/write by only revalidating permissions in selinux_file_permission if the task or inode labels have changed or the policy has changed since the open-time check. A new LSM hook, security_dentry_open, is added to capture the necessary state at open time to allow this optimization. (see http://marc.info/?l=selinux&m=118972995207740&w=2) Signed-off-by: Yuichi Nakamura<ynakam@hitachisoft.jp> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2006-12-02NetLabel: SELinux cleanupsPaul Moore
This patch does a lot of cleanup in the SELinux NetLabel support code. A summary of the changes include: * Use RCU locking for the NetLabel state variable in the skk_security_struct instead of using the inode_security_struct mutex. * Remove unnecessary parameters in selinux_netlbl_socket_post_create(). * Rename selinux_netlbl_sk_clone_security() to selinux_netlbl_sk_security_clone() to better fit the other NetLabel sk_security functions. * Improvements to selinux_netlbl_inode_permission() to help reduce the cost of the common case. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
2006-09-26[PATCH] SELinux: convert sbsec semaphore to a mutexEric Paris
This patch converts the semaphore in the superblock security struct to a mutex. No locking changes or other code changes are done. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>