The 'encrypted' key type defines its own payload format which contains a
symmetric key randomly generated that cannot be used directly to mount
an eCryptfs filesystem, because it expects an authentication token
structure.

This patch introduces the new format 'ecryptfs' that allows to store an
authentication token structure inside the encrypted key payload containing
a randomly generated symmetric key, as the same for the format 'default'.

More details about the usage of encrypted keys with the eCryptfs
filesystem can be found in the file 'Documentation/keys-ecryptfs.txt'.
Signed-off-by: NRoberto Sassu <roberto.sassu@polito.it>
Acked-by: NGianluca Ramunno <ramunno@polito.it>
Acked-by: NTyler Hicks <tyhicks@linux.vnet.ibm.com>
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>

This patch introduces a new parameter, called 'format', that defines the
format of data stored by encrypted keys. The 'default' format identifies
encrypted keys containing only the symmetric key, while other formats can
be defined to support additional information. The 'format' parameter is
written in the datablob produced by commands 'keyctl print' or
'keyctl pipe' and is integrity protected by the HMAC.
Signed-off-by: NRoberto Sassu <roberto.sassu@polito.it>
Acked-by: NGianluca Ramunno <ramunno@polito.it>
Acked-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>

Some debug messages have been added in the function datablob_parse() in
order to better identify errors returned when dealing with 'encrypted'
keys.

Changelog from version v4:
- made the debug messages more understandable 
Signed-off-by: NRoberto Sassu <roberto.sassu@polito.it>
Acked-by: NGianluca Ramunno <ramunno@polito.it>
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>

Valid key type prefixes for the parameter 'key-type' are: 'trusted' and
'user'.
Signed-off-by: NRoberto Sassu <roberto.sassu@polito.it>
Acked-by: NGianluca Ramunno <ramunno@polito.it>
Acked-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>

Do not dump the master key if an error is encountered during the request.
Signed-off-by: NRoberto Sassu <roberto.sassu@polito.it>
Acked-by: NGianluca Ramunno <ramunno@polito.it>
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>

Don't return EAGAIN to keyctl_assume_authority() to indicate that a key could
not be found (ENOKEY is only returned if a negative key is found).  Instead
return ENOKEY in both cases.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NJames Morris <jmorris@namei.org>

This is a rather hot function that is called with a potentially NULL
"struct common_audit_data" pointer argument.  And in that case it has to
provide and initialize its own dummy common_audit_data structure.

However, all the _common_ cases already pass it a real audit-data
structure, so that uncommon NULL case not only creates a silly run-time
test, more importantly it causes that function to have a big stack frame
for the dummy variable that isn't even used in the common case!

So get rid of that stupid run-time behavior, and make the (few)
functions that currently call with a NULL pointer just call a new helper
function instead (naturally called inode_has_perm_noapd(), since it has
no adp argument).

This makes the run-time test be a static code generation issue instead,
and allows for a much denser stack since none of the common callers need
the dummy structure.  And a denser stack not only means less stack space
usage, it means better cache behavior.  So we have a win-win-win from
this simplification: less code executed, smaller stack footprint, and
better cache behavior.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When invalid parameters are passed to apparmor_setprocattr a NULL deref
oops occurs when it tries to record an audit message. This is because
it is passing NULL for the profile parameter for aa_audit. But aa_audit
now requires that the profile passed is not NULL.

Fix this by passing the current profile on the task that is trying to
setprocattr.
Signed-off-by: NKees Cook <kees@ubuntu.com>
Signed-off-by: NJohn Johansen <john.johansen@canonical.com>
Cc: stable@kernel.org
Signed-off-by: NJames Morris <jmorris@namei.org>

Right now security_get_user_sids() will pass in a NULL avd pointer to
avc_has_perm_noaudit(), which then forces that function to have a dummy
entry for that case and just generally test it.

Don't do it.  The normal callers all pass a real avd pointer, and this
helper function is incredibly hot.  So don't make avc_has_perm_noaudit()
do conditional stuff that isn't needed for the common case.

This also avoids some duplicated stack space.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add cgroup subsystem callbacks for per-thread attachment in atomic contexts

Add can_attach_task(), pre_attach(), and attach_task() as new callbacks
for cgroups's subsystem interface.  Unlike can_attach and attach, these
are for per-thread operations, to be called potentially many times when
attaching an entire threadgroup.

Also, the old "bool threadgroup" interface is removed, as replaced by
this.  All subsystems are modified for the new interface - of note is
cpuset, which requires from/to nodemasks for attach to be globally scoped
(though per-cpuset would work too) to persist from its pre_attach to
attach_task and attach.

This is a pre-patch for cgroup-procs-writable.patch.
Signed-off-by: NBen Blum <bblum@andrew.cmu.edu>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Reviewed-by: NPaul Menage <menage@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since this cred was not created with copy_creds(), it needs to get
initialized.  Otherwise use of syscall(__NR_keyctl, KEYCTL_SESSION_TO_PARENT);
can lead to a NULL deref.  Thanks to Robert for finding this.

But introduced by commit 47a150ed ("Cache user_ns in struct cred").
Signed-off-by: NSerge E. Hallyn <serge.hallyn@canonical.com>
Reported-by: NRobert Święcki <robert@swiecki.net>
Cc: David Howells <dhowells@redhat.com>
Cc: stable@kernel.org (2.6.39)
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There is no point in counting hits - we can calculate it from the number
of lookups and misses.

This makes the avc statistics a bit smaller, and makes the code
generation better too.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

You can turn off the avc cache stats, but distributions seem to not do
that (perhaps because several performance tuning how-to's talk about the
avc cache statistics).

Which is sad, because the code it generates is truly horrendous, with
the statistics update being sandwitched between get_cpu/put_cpu which in
turn causes preemption disables etc.  We're talking ten+ instructions
just to increment a per-cpu variable in some pretty hot code.

Fix the craziness by just using 'this_cpu_inc()' instead.  Suddenly we
only need a single 'inc' instruction to increment the statistics.  This
is quite noticeable in the incredibly hot avc_has_perm_noaudit()
function (which triggers all the statistics by virtue of doing an
avc_lookup() call).
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

move LSM-, credentials-, and keys-related files from Documentation/
  to Documentation/security/,
add Documentation/security/00-INDEX, and
update all occurrences of Documentation/<moved_file>
  to Documentation/security/<moved_file>.

The filename_trans rule processing has some printk(KERN_ERR ) messages
which were intended as debug aids in creating the code but weren't removed
before it was submitted.  Remove them.
Reported-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NEric Paris <eparis@redhat.com>

In tomoyo_correct_domain() since 2.6.36, TOMOYO was by error validating
"<kernel>" + "/foo/\" + "/bar" when "<kernel> /foo/\* /bar" was given.
As a result, legal domainnames like "<kernel> /foo/\* /bar" are rejected.
Reported-by: NHayama Yossihiro <yossi@yedo.src.co.jp>
Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: NJames Morris <jmorris@namei.org>

In the interest of keeping userspace from having to create new root
filesystems all the time, let's follow the lead of the other in-kernel
filesystems and provide a proper mount point for it in sysfs.

For selinuxfs, this mount point should be in /sys/fs/selinux/

Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Lennart Poettering <mzerqung@0pointer.de>
Cc: Daniel J Walsh <dwalsh@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
[include kobject.h - Eric Paris]
[use selinuxfs_obj throughout - Eric Paris]
Signed-off-by: NEric Paris <eparis@redhat.com>

The rcu callback sel_netif_free() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(sel_netif_free).
Signed-off-by: NLai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

The rcu callback user_update_rcu_disposal() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(user_update_rcu_disposal).
Signed-off-by: NLai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

Change flex_array_prealloc to take the number of elements for which space
should be allocated instead of the last (inclusive) element. Users
and documentation are updated accordingly.  flex_arrays got introduced before
they had users.  When folks started using it, they ended up needing a
different API than was coded up originally.  This swaps over to the API that
folks apparently need.
Based-on-patch-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NEric Paris <eparis@redhat.com>
Tested-by: NChris Richards <gizmo@giz-works.com>
Acked-by: NDave Hansen <dave@linux.vnet.ibm.com>
Cc: stable@kernel.org [2.6.38+]

New inodes are created in a two stage process.  We first will compute the
label on a new inode in security_inode_create() and check if the
operation is allowed.  We will then actually re-compute that same label and
apply it in security_inode_init_security().  The change to do new label
calculations based in part on the last component of the path name only
passed the path component information all the way down the
security_inode_init_security hook.  Down the security_inode_create hook the
path information did not make it past may_create.  Thus the two calculations
came up differently and the permissions check might not actually be against
the label that is created.  Pass and use the same information in both places
to harmonize the calculations and checks.
Reported-by: NDominick Grift <domg472@gmail.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

We currently have inode_has_perm and dentry_has_perm.  dentry_has_perm just
calls inode_has_perm with additional audit data.  But dentry_has_perm can
take either a dentry or a path.  Split those to make the code obvious and
to fix the previous problem where I thought dentry_has_perm always had a
valid dentry and mnt.
Signed-off-by: NEric Paris <eparis@redhat.com>

Change flex_array_prealloc to take the number of elements for which space
should be allocated instead of the last (inclusive) element. Users
and documentation are updated accordingly.  flex_arrays got introduced before
they had users.  When folks started using it, they ended up needing a
different API than was coded up originally.  This swaps over to the API that
folks apparently need.
Based-on-patch-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NEric Paris <eparis@redhat.com>
Tested-by: NChris Richards <gizmo@giz-works.com>
Acked-by: NDave Hansen <dave@linux.vnet.ibm.com>
Cc: stable@kernel.org [2.6.38+]

New inodes are created in a two stage process.  We first will compute the
label on a new inode in security_inode_create() and check if the
operation is allowed.  We will then actually re-compute that same label and
apply it in security_inode_init_security().  The change to do new label
calculations based in part on the last component of the path name only
passed the path component information all the way down the
security_inode_init_security hook.  Down the security_inode_create hook the
path information did not make it past may_create.  Thus the two calculations
came up differently and the permissions check might not actually be against
the label that is created.  Pass and use the same information in both places
to harmonize the calculations and checks.
Reported-by: NDominick Grift <domg472@gmail.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

To shorten the list we need to run if filename trans rules exist for the type
of the given parent directory I put them in a hashtable.  Given the policy we
are expecting to use in Fedora this takes the worst case list run from about
5,000 entries to 17.
Signed-off-by: NEric Paris <eparis@redhat.com>
Reviewed-by: NJames Morris <jmorris@namei.org>

Instead of a hashtab entry counter function only useful for range
transition rules make a function generic for any hashtable to use.
Signed-off-by: NEric Paris <eparis@redhat.com>
Reviewed-by: NJames Morris <jmorris@namei.org>

We have custom debug functions like rangetr_hash_eval and symtab_hash_eval
which do the same thing.  Just create a generic function that takes the name
of the hash table as an argument instead of having custom functions.
Signed-off-by: NEric Paris <eparis@redhat.com>
Reviewed-by: NJames Morris <jmorris@namei.org>

Right now we walk to filename trans rule list for every inode that is
created.  First passes at policy using this facility creates around 5000
filename trans rules.  Running a list of 5000 entries every time is a bad
idea.  This patch adds a new ebitmap to policy which has a bit set for each
ttype that has at least 1 filename trans rule.  Thus when an inode is
created we can quickly determine if any rules exist for this parent
directory type and can skip the list if we know there is definitely no
relevant entry.
Signed-off-by: NEric Paris <eparis@redhat.com>
Reviewed-by: NJames Morris <jmorris@namei.org>

filename_compute_type() takes as arguments the numeric value of the type of
the subject and target.  It does not take a context.  Thus the names are
misleading.  Fix the argument names.
Signed-off-by: NEric Paris <eparis@redhat.com>
Reviewed-by: NJames Morris <jmorris@namei.org>

filename_compute_type used to take a qstr, but it now takes just a name.
Fix the comments to indicate it is an objname, not a qstr.
Signed-off-by: NEric Paris <eparis@redhat.com>

Now that the security modules can decide whether they support the
dcache RCU walk or not it's possible to make selinux a bit more
RCU friendly.  The SELinux AVC and security server access decision
code is RCU safe.  A specific piece of the LSM audit code may not
be RCU safe.

This patch makes the VFS RCU walk retry if it would hit the non RCU
safe chunk of code.  It will normally just work under RCU.  This is
done simply by passing the VFS RCU state as a flag down into the
avc_audit() code and returning ECHILD there if it would have an issue.
Based-on-patch-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

smack_file_lock has a struct path, so use that instead of only the
dentry.
Signed-off-by: NEric Paris <eparis@redhat.com>
Acked-by: NCasey Schaufler <casey@schaufler-ca.com>

This patch separates and audit message that only contains a dentry from
one that contains a full path.  This allows us to make it harder to
misuse the interfaces or for the interfaces to be implemented wrong.
Signed-off-by: NEric Paris <eparis@redhat.com>
Acked-by: NCasey Schaufler <casey@schaufler-ca.com>

The lsm common audit code has wacky contortions making sure which pieces
of information are set based on if it was given a path, dentry, or
inode.  Split this into path and inode to get rid of some of the code
complexity.
Signed-off-by: NEric Paris <eparis@redhat.com>
Acked-by: NCasey Schaufler <casey@schaufler-ca.com>

Now that the security modules can decide whether they support the
dcache RCU walk or not it's possible to make selinux a bit more
RCU friendly.  The SELinux AVC and security server access decision
code is RCU safe.  A specific piece of the LSM audit code may not
be RCU safe.

This patch makes the VFS RCU walk retry if it would hit the non RCU
safe chunk of code.  It will normally just work under RCU.  This is
done simply by passing the VFS RCU state as a flag down into the
avc_audit() code and returning ECHILD there if it would have an issue.
Based-on-patch-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

Right now all RCU walks fall back to reference walk when CONFIG_SECURITY
is enabled, even though just the standard capability module is active.
This is because security_inode_exec_permission unconditionally fails
RCU walks.

Move this decision to the low level security module. This requires
passing the RCU flags down the security hook. This way at least
the capability module and a few easy cases in selinux/smack work
with RCU walks with CONFIG_SECURITY=y
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NEric Paris <eparis@redhat.com>

The len should be an size_t but is a ssize_t.  Easy enough fix to silence
build warnings.  We have no need for signed-ness.
Signed-off-by: NEric Paris <eparis@redhat.com>
Reviewed-by: NJames Morris <jmorris@namei.org>

If one builds a kernel without CONFIG_BUG there are a number of 'may be
used uninitialized' warnings.  Silence these by returning after the BUG().
Signed-off-by: NEric Paris <eparis@redhat.com>
Reviewed-by: NJames Morris <jmorris@namei.org>

Right now all RCU walks fall back to reference walk when CONFIG_SECURITY
is enabled, even though just the standard capability module is active.
This is because security_inode_exec_permission unconditionally fails
RCU walks.

Move this decision to the low level security module. This requires
passing the RCU flags down the security hook. This way at least
the capability module and a few easy cases in selinux/smack work
with RCU walks with CONFIG_SECURITY=y
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Acked-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The filename_trans rule processing has some printk(KERN_ERR ) messages
which were intended as debug aids in creating the code but weren't removed
before it was submitted.  Remove them.
Signed-off-by: NEric Paris <eparis@redhat.com>