This reverts commit 4da6daf4.

Unfortunately, the commit in question caused problems with Bluetooth
devices, specifically it caused them to get caught in the newly
created BUG_ON() check.  The AF_ALG problem still exists, but will be
addressed in a future patch.

Cc: stable@vger.kernel.org
Signed-off-by: NPaul Moore <pmoore@redhat.com>

In order to validate the contents of firmware being loaded, there must be
a hook to evaluate any loaded firmware that wasn't built into the kernel
itself. Without this, there is a risk that a root user could load malicious
firmware designed to mount an attack against kernel memory (e.g. via DMA).
Signed-off-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NTakashi Iwai <tiwai@suse.de>

The sock_graft() hook has special handling for AF_INET, AF_INET, and
AF_UNIX sockets as those address families have special hooks which
label the sock before it is attached its associated socket.
Unfortunately, the sock_graft() hook was missing a default approach
to labeling sockets which meant that any other address family which
made use of connections or the accept() syscall would find the
returned socket to be in an "unlabeled" state.  This was recently
demonstrated by the kcrypto/AF_ALG subsystem and the newly released
cryptsetup package (cryptsetup v1.6.5 and later).

This patch preserves the special handling in selinux_sock_graft(),
but adds a default behavior - setting the sock's label equal to the
associated socket - which resolves the problem with AF_ALG and
presumably any other address family which makes use of accept().

Cc: stable@vger.kernel.org
Signed-off-by: NPaul Moore <pmoore@redhat.com>
Tested-by: NMilan Broz <gmazyland@gmail.com>

Add flags to security_path_rename() and security_inode_rename() hooks.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Reviewed-by: NJ. Bruce Fields <bfields@redhat.com>

Move the flags representing required permission to linux/key.h as the perm
parameter of security_key_permission() is in terms of them - and not the
permissions mask flags used in key->perm.

Whilst we're at it:

 (1) Rename them to be KEY_NEED_xxx rather than KEY_xxx to avoid collisions
     with symbols in uapi/linux/input.h.

 (2) Don't use key_perm_t for a mask of required permissions, but rather limit
     it to the permissions mask attached to the key and arguments related
     directly to that.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Tested-by: NDmitry Kasatkin <d.kasatkin@samsung.com>

security_xfrm_policy_alloc can be called in atomic context so the
allocation should be done with GFP_ATOMIC. Add an argument to let the
callers choose the appropriate way. In order to do so a gfp argument
needs to be added to the method xfrm_policy_alloc_security in struct
security_operations and to the internal function
selinux_xfrm_alloc_user. After that switch to GFP_ATOMIC in the atomic
callers and leave GFP_KERNEL as before for the rest.
The path that needed the gfp argument addition is:
security_xfrm_policy_alloc -> security_ops.xfrm_policy_alloc_security ->
all users of xfrm_policy_alloc_security (e.g. selinux_xfrm_policy_alloc) ->
selinux_xfrm_alloc_user (here the allocation used to be GFP_KERNEL only)

Now adding a gfp argument to selinux_xfrm_alloc_user requires us to also
add it to security_context_to_sid which is used inside and prior to this
patch did only GFP_KERNEL allocation. So add gfp argument to
security_context_to_sid and adjust all of its callers as well.

CC: Paul Moore <paul@paul-moore.com>
CC: Dave Jones <davej@redhat.com>
CC: Steffen Klassert <steffen.klassert@secunet.com>
CC: Fan Du <fan.du@windriver.com>
CC: David S. Miller <davem@davemloft.net>
CC: LSM list <linux-security-module@vger.kernel.org>
CC: SELinux list <selinux@tycho.nsa.gov>
Signed-off-by: NNikolay Aleksandrov <nikolay@redhat.com>
Acked-by: NPaul Moore <paul@paul-moore.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

The xfrm_state_alloc_security() LSM hook implementation is really a
multiplexed hook with two different behaviors depending on the
arguments passed to it by the caller.  This patch splits the LSM hook
implementation into two new hook implementations, which match the
LSM hooks in the rest of the kernel:

 * xfrm_state_alloc
 * xfrm_state_alloc_acquire

Also included in this patch are the necessary changes to the SELinux
code; no other LSMs are affected.
Signed-off-by: NPaul Moore <pmoore@redhat.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

Since everybody sets kstrdup()ed constant string to "struct xattr"->name but
nobody modifies "struct xattr"->name , we can omit kstrdup() and its failure
checking by constifying ->name member of "struct xattr".
Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Joel Becker <jlbec@evilplan.org> [ocfs2]
Acked-by: NSerge E. Hallyn <serge.hallyn@ubuntu.com>
Acked-by: NCasey Schaufler <casey@schaufler-ca.com>
Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
Reviewed-by: NPaul Moore <paul@paul-moore.com>
Tested-by: NPaul Moore <paul@paul-moore.com>
Acked-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

There currently doesn't exist a labeling type that is adequate for use with
labeled NFS. Since NFS doesn't really support xattrs we can't use the use xattr
labeling behavior. For this we developed a new labeling type. The native
labeling type is used solely by NFS to ensure NFS inodes are labeled at runtime
by the NFS code instead of relying on the SELinux security server on the client
end.
Acked-by: NEric Paris <eparis@redhat.com>
Acked-by: NJames Morris <james.l.morris@oracle.com>
Signed-off-by: NMatthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: NMiguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: NPhua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: NKhin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

There is no way to differentiate if a text mount option is passed from user
space or the kernel. A flags field is being added to the
security_sb_set_mnt_opts hook to allow for in kernel security flags to be sent
to the LSM for processing in addition to the text options received from mount.
This patch also updated existing code to fix compilation errors.
Acked-by: NEric Paris <eparis@redhat.com>
Acked-by: NJames Morris <james.l.morris@oracle.com>
Signed-off-by: NDavid P. Quigley <dpquigl@tycho.nsa.gov>
Signed-off-by: NMiguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: NPhua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: NKhin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The interface to request security labels from user space is the xattr
interface. When requesting the security label from an NFS server it is
important to make sure the requested xattr actually is a MAC label. This allows
us to make sure that we get the desired semantics from the attribute instead of
something else such as capabilities or a time based LSM.
Acked-by: NEric Paris <eparis@redhat.com>
Acked-by: NJames Morris <james.l.morris@oracle.com>
Signed-off-by: NMatthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: NMiguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: NPhua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: NKhin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

There is a time where we need to calculate a context without the
inode having been created yet. To do this we take the negative dentry and
calculate a context based on the process and the parent directory contexts.
Acked-by: NEric Paris <eparis@redhat.com>
Acked-by: NJames Morris <james.l.morris@oracle.com>
Signed-off-by: NMatthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: NMiguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: NPhua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: NKhin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: NSteve Dickson <steved@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Make it clear that cap_inode_getsecctx shouldn't return success without
filling in the context data.
Acked-by: NSerge E. Hallyn <serge.hallyn@ubuntu.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

Unfortunately we didn't catch the missing comments earlier when the
patch was merged.
Signed-off-by: NPaul Moore <pmoore@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 90ba9b19 (tcp: tcp_make_synack() can use alloc_skb())
broke certain SELinux/NetLabel configurations by no longer correctly
assigning the sock to the outgoing SYNACK packet.

Cost of atomic operations on the LISTEN socket is quite big,
and we would like it to happen only if really needed.

This patch introduces a new security_ops->skb_owned_by() method,
that is a void operation unless selinux is active.
Reported-by: NMiroslav Vadkerti <mvadkert@redhat.com>
Diagnosed-by: NPaul Moore <pmoore@redhat.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-security-module@vger.kernel.org
Acked-by: NJames Morris <james.l.morris@oracle.com>
Tested-by: NPaul Moore <pmoore@redhat.com>
Acked-by: NPaul Moore <pmoore@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I had the following problem reported a while back. If you mount the
same filesystem twice using NFSv4 with different contexts, then the
second context= option is ignored. For instance:

    # mount server:/export /mnt/test1
    # mount server:/export /mnt/test2 -o context=system_u:object_r:tmp_t:s0
    # ls -dZ /mnt/test1
    drwxrwxrwt. root root system_u:object_r:nfs_t:s0       /mnt/test1
    # ls -dZ /mnt/test2
    drwxrwxrwt. root root system_u:object_r:nfs_t:s0       /mnt/test2

When we call into SELinux to set the context of a "cloned" superblock,
it will currently just bail out when it notices that we're reusing an
existing superblock. Since the existing superblock is already set up and
presumably in use, we can't go overwriting its context with the one from
the "original" sb. Because of this, the second context= option in this
case cannot take effect.

This patch fixes this by turning security_sb_clone_mnt_opts into an int
return operation. When it finds that the "new" superblock that it has
been handed is already set up, it checks to see whether the contexts on
the old superblock match it. If it does, then it will just return
success, otherwise it'll return -EBUSY and emit a printk to tell the
admin why the second mount failed.

Note that this patch may cause casualties. The NFSv4 code relies on
being able to walk down to an export from the pseudoroot. If you mount
filesystems that are nested within one another with different contexts,
then this patch will make those mounts fail in new and "exciting" ways.

For instance, suppose that /export is a separate filesystem on the
server:

    # mount server:/ /mnt/test1
    # mount salusa:/export /mnt/test2 -o context=system_u:object_r:tmp_t:s0
    mount.nfs: an incorrect mount option was specified

...with the printk in the ring buffer. Because we *might* eventually
walk down to /mnt/test1/export, the mount is denied due to this patch.
The second mount needs the pseudoroot superblock, but that's already
present with the wrong context.

OTOH, if we mount these in the reverse order, then both mounts work,
because the pseudoroot superblock created when mounting /export is
discarded once that mount is done. If we then however try to walk into
that directory, the automount fails for the similar reasons:

    # cd /mnt/test1/scratch/
    -bash: cd: /mnt/test1/scratch: Device or resource busy

The story I've gotten from the SELinux folks that I've talked to is that
this is desirable behavior. In SELinux-land, mounting the same data
under different contexts is wrong -- there can be only one.

Cc: Steve Dickson <steved@redhat.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Acked-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

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: NPaul Moore <pmoore@redhat.com>
Acked-by: NEric Paris <eparis@parisplace.org>
Tested-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that kernel module origins can be reasoned about, provide a hook to
the LSMs to make policy decisions about the module file. This will let
Chrome OS enforce that loadable kernel modules can only come from its
read-only hash-verified root filesystem. Other LSMs can, for example,
read extended attributes for signatures, etc.
Signed-off-by: NKees Cook <keescook@chromium.org>
Acked-by: NSerge E. Hallyn <serge.hallyn@canonical.com>
Acked-by: NEric Paris <eparis@redhat.com>
Acked-by: NMimi Zohar <zohar@us.ibm.com>
Acked-by: NJames Morris <james.l.morris@oracle.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Commit 1ad75b9e ("c/r: prctl: add minimal address test to
PR_SET_MM") added some address checking to prctl_set_mm() used by
checkpoint-restore.  This causes a build error for no-MMU systems:

   kernel/sys.c: In function 'prctl_set_mm':
   kernel/sys.c:1868:34: error: 'mmap_min_addr' undeclared (first use in this function)

The test for mmap_min_addr doesn't make a lot of sense for no-MMU code
as noted in commit 6e141546 ("NOMMU: Optimise away the
{dac_,}mmap_min_addr tests").

This patch defines mmap_min_addr as 0UL in the no-MMU case so that the
compiler will optimize away tests for "addr < mmap_min_addr".
Signed-off-by: NMark Salter <msalter@redhat.com>
Reviewed-by: NCyrill Gorcunov <gorcunov@openvz.org>
Cc: <stable@vger.kernel.org>	[3.6.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Don't make the security modules deal with raw user space uid and
gids instead pass in a kuid_t and a kgid_t so that security modules
only have to deal with internal kernel uids and gids.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: James Morris <james.l.morris@oracle.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: NSerge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

Unconditionally call Yama when CONFIG_SECURITY_YAMA_STACKED is selected,
no matter what LSM module is primary.

Ubuntu and Chrome OS already carry patches to do this, and Fedora
has voiced interest in doing this as well. Instead of having multiple
distributions (or LSM authors) carrying these patches, just allow Yama
to be called unconditionally when selected by the new CONFIG.
Signed-off-by: NKees Cook <keescook@chromium.org>
Acked-by: NSerge E. Hallyn <serge.hallyn@canonical.com>
Acked-by: NEric Paris <eparis@redhat.com>
Acked-by: NJohn Johansen <john.johansen@canonical.com>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

The higher ptrace restriction levels should be blocking even
PTRACE_TRACEME requests. The comments in the LSM documentation are
misleading about when the checks happen (the parent does not go through
security_ptrace_access_check() on a PTRACE_TRACEME call).
Signed-off-by: NKees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org # 3.5.x and later
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... i.e. file-dependent and address-dependent checks.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... switch callers.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

With this change, calling
  prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)
disables privilege granting operations at execve-time.  For example, a
process will not be able to execute a setuid binary to change their uid
or gid if this bit is set.  The same is true for file capabilities.

Additionally, LSM_UNSAFE_NO_NEW_PRIVS is defined to ensure that
LSMs respect the requested behavior.

To determine if the NO_NEW_PRIVS bit is set, a task may call
  prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
It returns 1 if set and 0 if it is not set. If any of the arguments are
non-zero, it will return -1 and set errno to -EINVAL.
(PR_SET_NO_NEW_PRIVS behaves similarly.)

This functionality is desired for the proposed seccomp filter patch
series.  By using PR_SET_NO_NEW_PRIVS, it allows a task to modify the
system call behavior for itself and its child tasks without being
able to impact the behavior of a more privileged task.

Another potential use is making certain privileged operations
unprivileged.  For example, chroot may be considered "safe" if it cannot
affect privileged tasks.

Note, this patch causes execve to fail when PR_SET_NO_NEW_PRIVS is
set and AppArmor is in use.  It is fixed in a subsequent patch.
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Signed-off-by: NWill Drewry <wad@chromium.org>
Acked-by: NEric Paris <eparis@redhat.com>
Acked-by: NKees Cook <keescook@chromium.org>

v18: updated change desc
v17: using new define values as per 3.4
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

dentry_open takes a file, rename it to file_open
Signed-off-by: NEric Paris <eparis@redhat.com>

unix_may_send hook has the prototype:

int (*unix_may_send) (struct socket *sock, struct socket *other)

so the documentation is wrongly referring to the second argument as @sock.
Signed-off-by: NJavier Martinez Canillas <javier@dowhile0.org>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Trim security.h
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NJames Morris <jmorris@namei.org>

Collapse security_vm_enough_memory() variants into a single function.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NJames Morris <jmorris@namei.org>

The current LSM interface to cred_free is not sufficient for allowing
an LSM to track the life and death of a task. This patch adds the
task_free hook so that an LSM can clean up resources on task death.
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NJames Morris <jmorris@namei.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Once upon a time netlink was not sync and we had to get the effective
capabilities from the skb that was being received.  Today we instead get
the capabilities from the current task.  This has rendered the entire
purpose of the hook moot as it is now functionally equivalent to the
capable() call.
Signed-off-by: NEric Paris <eparis@redhat.com>

The name security_real_capable and security_real_capable_noaudit just don't
make much sense to me.  Convert them to use security_capable and
security_capable_noaudit.
Signed-off-by: NEric Paris <eparis@redhat.com>
Acked-by: NSerge E. Hallyn <serge.hallyn@canonical.com>

Exactly like security_capable except don't audit any denials.  This is for
places where the kernel may make decisions about what to do if a task has a
given capability, but which failing that capability is not a sign of a
security policy violation.  An example is checking if a task has
CAP_SYS_ADMIN to lower it's likelyhood of being killed by the oom killer.
This check is not a security violation if it is denied.
Signed-off-by: NEric Paris <eparis@redhat.com>
Acked-by: NSerge E. Hallyn <serge.hallyn@canonical.com>

security_capable takes ns, cred, cap.  But the LSM capable() hook takes
cred, ns, cap.  The capability helper functions also take cred, ns, cap.
Rather than flip argument order just to flip it back, leave them alone.
Heck, this should be a little faster since argument will be in the right
place!
Signed-off-by: NEric Paris <eparis@redhat.com>

The capabilities framework is based around credentials, not necessarily the
current task.  Yet we still passed the current task down into LSMs from the
security_capable() LSM hook as if it was a meaningful portion of the security
decision.  This patch removes the 'generic' passing of current and instead
forces individual LSMs to use current explicitly if they think it is
appropriate.  In our case those LSMs are SELinux and AppArmor.

I believe the AppArmor use of current is incorrect, but that is wholely
unrelated to this patch.  This patch does not change what AppArmor does, it
just makes it clear in the AppArmor code that it is doing it.

The SELinux code still uses current in it's audit message, which may also be
wrong and needs further investigation.  Again this is NOT a change, it may
have always been wrong, this patch just makes it clear what is happening.
Signed-off-by: NEric Paris <eparis@redhat.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>