Paul Moore [Thu, 9 Jun 2016 14:56:02 +0000 (10:56 -0400)]
netlabel: handle sparse category maps in netlbl_catmap_getlong()
In cases where the category bitmap is sparse enough that gaps exist
between netlbl_lsm_catmap structs, callers to netlbl_catmap_getlong()
could find themselves prematurely ending their search through the
category bitmap. Further, the methods used to calculate the 'idx'
and 'off' values were incorrect for bitmaps this large. This patch
changes the netlbl_catmap_getlong() behavior so that it always skips
over gaps and calculates the index and offset values correctly.
The existing ebitmap_netlbl_import() code didn't correctly handle the
case where the ebitmap_node was not aligned/sized to a power of two,
this patch fixes this (on x86_64 ebitmap_node contains six bitmaps
making a range of 0..383).
Paul Moore [Mon, 6 Jun 2016 19:17:20 +0000 (15:17 -0400)]
netlabel: add address family checks to netlbl_{sock,req}_delattr()
It seems risky to always rely on the caller to ensure the socket's
address family is correct before passing it to the NetLabel kAPI,
especially since we see at least one LSM which didn't. Add address
family checks to the *_delattr() functions to help prevent future
problems.
Cc: <stable@vger.kernel.org> Reported-by: Maninder Singh <maninder1.s@samsung.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
Stephen Smalley [Mon, 23 May 2016 14:54:11 +0000 (10:54 -0400)]
selinux: Only apply bounds checking to source types
The current bounds checking of both source and target types
requires allowing any domain that has access to the child
domain to also have the same permissions to the parent, which
is undesirable. Drop the target bounds checking.
KaiGai Kohei originally removed all use of target bounds in
commit 7d52a155e38d ("selinux: remove dead code in
type_attribute_bounds_av()") but this was reverted in
commit 2ae3ba39389b ("selinux: libsepol: remove dead code in
check_avtab_hierarchy_callback()") because it would have
required explicitly allowing the parent any permissions
to the child that the child is allowed to itself.
This change in contrast retains the logic for the case where both
source and target types are bounded, thereby allowing access
if the parent of the source is allowed the corresponding
permissions to the parent of the target. Further, this change
reworks the logic such that we only perform a single computation
for each case and there is no ambiguity as to how to resolve
a bounds violation.
Under the new logic, if the source type and target types are both
bounded, then the parent of the source type must be allowed the same
permissions to the parent of the target type. If only the source
type is bounded, then the parent of the source type must be allowed
the same permissions to the target type.
Examples of the new logic and comparisons with the old logic:
1. If we have:
typebounds A B;
then:
allow B self:process <permissions>;
will satisfy the bounds constraint iff:
allow A self:process <permissions>;
is also allowed in policy.
Under the old logic, the allow rule on B satisfies the
bounds constraint if any of the following three are allowed:
allow A B:process <permissions>; or
allow B A:process <permissions>; or
allow A self:process <permissions>;
However, either of the first two ultimately require the third to
satisfy the bounds constraint under the old logic, and therefore
this degenerates to the same result (but is more efficient - we only
need to perform one compute_av call).
2. If we have:
typebounds A B;
typebounds A_exec B_exec;
then:
allow B B_exec:file <permissions>;
will satisfy the bounds constraint iff:
allow A A_exec:file <permissions>;
is also allowed in policy.
This is essentially the same as #1; it is merely included as
an example of dealing with object types related to a bounded domain
in a manner that satisfies the bounds relationship. Note that
this approach is preferable to leaving B_exec unbounded and having:
allow A B_exec:file <permissions>;
in policy because that would allow B's entrypoints to be used to
enter A. Similarly for _tmp or other related types.
3. If we have:
typebounds A B;
and an unbounded type T, then:
allow B T:file <permissions>;
will satisfy the bounds constraint iff:
allow A T:file <permissions>;
is allowed in policy.
The old logic would have been identical for this example.
4. If we have:
typebounds A B;
and an unbounded domain D, then:
allow D B:unix_stream_socket <permissions>;
is not subject to any bounds constraints under the new logic
because D is not bounded. This is desirable so that we can
allow a domain to e.g. connectto a child domain without having
to allow it to do the same to its parent.
The old logic would have required:
allow D A:unix_stream_socket <permissions>;
to also be allowed in policy.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: re-wrapped description to appease checkpatch.pl] Signed-off-by: Paul Moore <paul@paul-moore.com>
Kees Cook [Tue, 17 May 2016 08:45:52 +0000 (01:45 -0700)]
LSM: LoadPin: provide enablement CONFIG
Instead of being enabled by default when SECURITY_LOADPIN is selected,
provide an additional (default off) config to determine the boot time
behavior. As before, the "loadpin.enabled=0/1" kernel parameter remains
available.
Suggested-by: James Morris <jmorris@namei.org> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.l.morris@oracle.com>
David Howells [Wed, 4 May 2016 16:20:20 +0000 (17:20 +0100)]
Merge branch 'keys-trust' into keys-next
Here's a set of patches that changes how certificates/keys are determined
to be trusted. That's currently a two-step process:
(1) Up until recently, when an X.509 certificate was parsed - no matter
the source - it was judged against the keys in .system_keyring,
assuming those keys to be trusted if they have KEY_FLAG_TRUSTED set
upon them.
This has just been changed such that any key in the .ima_mok keyring,
if configured, may also be used to judge the trustworthiness of a new
certificate, whether or not the .ima_mok keyring is meant to be
consulted for whatever process is being undertaken.
If a certificate is determined to be trustworthy, KEY_FLAG_TRUSTED
will be set upon a key it is loaded into (if it is loaded into one),
no matter what the key is going to be loaded for.
(2) If an X.509 certificate is loaded into a key, then that key - if
KEY_FLAG_TRUSTED gets set upon it - can be linked into any keyring
with KEY_FLAG_TRUSTED_ONLY set upon it. This was meant to be the
system keyring only, but has been extended to various IMA keyrings.
A user can at will link any key marked KEY_FLAG_TRUSTED into any
keyring marked KEY_FLAG_TRUSTED_ONLY if the relevant permissions masks
permit it.
These patches change that:
(1) Trust becomes a matter of consulting the ring of trusted keys supplied
when the trust is evaluated only.
(2) Every keyring can be supplied with its own manager function to
restrict what may be added to that keyring. This is called whenever a
key is to be linked into the keyring to guard against a key being
created in one keyring and then linked across.
This function is supplied with the keyring and the key type and
payload[*] of the key being linked in for use in its evaluation. It
is permitted to use other data also, such as the contents of other
keyrings such as the system keyrings.
[*] The type and payload are supplied instead of a key because as an
optimisation this function may be called whilst creating a key and
so may reject the proposed key between preparse and allocation.
(3) A default manager function is provided that permits keys to be
restricted to only asymmetric keys that are vouched for by the
contents of the system keyring.
A second manager function is provided that just rejects with EPERM.
(4) A key allocation flag, KEY_ALLOC_BYPASS_RESTRICTION, is made available
so that the kernel can initialise keyrings with keys that form the
root of the trust relationship.
(5) KEY_FLAG_TRUSTED and KEY_FLAG_TRUSTED_ONLY are removed, along with
key_preparsed_payload::trusted.
This change also makes it possible in future for userspace to create a private
set of trusted keys and then to have it sealed by setting a manager function
where the private set is wholly independent of the kernel's trust
relationships.
Further changes in the set involve extracting certain IMA special keyrings
and making them generally global:
(*) .system_keyring is renamed to .builtin_trusted_keys and remains read
only. It carries only keys built in to the kernel. It may be where
UEFI keys should be loaded - though that could better be the new
secondary keyring (see below) or a separate UEFI keyring.
(*) An optional secondary system keyring (called .secondary_trusted_keys)
is added to replace the IMA MOK keyring.
(*) Keys can be added to the secondary keyring by root if the keys can
be vouched for by either ring of system keys.
(*) Module signing and kexec only use .builtin_trusted_keys and do not use
the new secondary keyring.
(*) Config option SYSTEM_TRUSTED_KEYS now depends on ASYMMETRIC_KEY_TYPE as
that's the only type currently permitted on the system keyrings.
(*) A new config option, IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY,
is provided to allow keys to be added to IMA keyrings, subject to the
restriction that such keys are validly signed by a key already in the
system keyrings.
If this option is enabled, but secondary keyrings aren't, additions to
the IMA keyrings will be restricted to signatures verifiable by keys in
the builtin system keyring only.
Signed-off-by: David Howells <dhowells@redhat.com>
Mimi Zohar [Tue, 1 Mar 2016 00:52:05 +0000 (19:52 -0500)]
ima: add support for creating files using the mknodat syscall
Commit 3034a14 "ima: pass 'opened' flag to identify newly created files"
stopped identifying empty files as new files. However new empty files
can be created using the mknodat syscall. On systems with IMA-appraisal
enabled, these empty files are not labeled with security.ima extended
attributes properly, preventing them from subsequently being opened in
order to write the file data contents. This patch defines a new hook
named ima_post_path_mknod() to mark these empty files, created using
mknodat, as new in order to allow the file data contents to be written.
In addition, files with security.ima xattrs containing a file signature
are considered "immutable" and can not be modified. The file contents
need to be written, before signing the file. This patch relaxes this
requirement for new files, allowing the file signature to be written
before the file contents.
Changelog:
- defer identifying files with signatures stored as security.ima
(based on Dmitry Rozhkov's comments)
- removing tests (eg. dentry, dentry->d_inode, inode->i_size == 0)
(based on Al's review)
Mimi Zohar [Mon, 29 Feb 2016 13:30:12 +0000 (08:30 -0500)]
ima: fix ima_inode_post_setattr
Changing file metadata (eg. uid, guid) could result in having to
re-appraise a file's integrity, but does not change the "new file"
status nor the security.ima xattr. The IMA_PERMIT_DIRECTIO and
IMA_DIGSIG_REQUIRED flags are policy rule specific. This patch
only resets these flags, not the IMA_NEW_FILE or IMA_DIGSIG flags.
With this patch, changing the file timestamp will not remove the
file signature on new files.
Dmitry Kasatkin [Sun, 26 Oct 2014 10:42:07 +0000 (12:42 +0200)]
vfs: forbid write access when reading a file into memory
This patch is based on top of the "vfs: support for a common kernel file
loader" patch set. In general when the kernel is reading a file into
memory it does not want anything else writing to it.
The kernel currently only forbids write access to a file being executed.
This patch extends this locking to files being read by the kernel.
Changelog:
- moved function to kernel_read_file() - Mimi
- updated patch description - Mimi
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Reviewed-by: Luis R. Rodriguez <mcgrof@kernel.org> Acked-by: Kees Cook <keescook@chromium.org>
When I was fixing up const recommendations from checkpatch.pl, I went
overboard. This fixes the warning (during a W=1 build):
include/linux/fs.h:2627:74: warning: type qualifiers ignored on function return type [-Wignored-qualifiers]
static inline const char * const kernel_read_file_id_str(enum kernel_read_file_id id)
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.l.morris@oracle.com>
Stephen Smalley [Fri, 8 Apr 2016 17:55:03 +0000 (13:55 -0400)]
selinux: apply execstack check on thread stacks
The execstack check was only being applied on the main
process stack. Thread stacks allocated via mmap were
only subject to the execmem permission check. Augment
the check to apply to the current thread stack as well.
Note that this does NOT prevent making a different thread's
stack executable.
Suggested-by: Nick Kralevich <nnk@google.com> Acked-by: Nick Kralevich <nnk@google.com> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
Stephen Smalley [Fri, 8 Apr 2016 17:52:00 +0000 (13:52 -0400)]
selinux: distinguish non-init user namespace capability checks
Distinguish capability checks against a target associated
with the init user namespace versus capability checks against
a target associated with a non-init user namespace by defining
and using separate security classes for the latter.
This is needed to support e.g. Chrome usage of user namespaces
for the Chrome sandbox without needing to allow Chrome to also
exercise capabilities on targets in the init user namespace.
Suggested-by: Dan Walsh <dwalsh@redhat.com> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
This LSM enforces that kernel-loaded files (modules, firmware, etc)
must all come from the same filesystem, with the expectation that
such a filesystem is backed by a read-only device such as dm-verity
or CDROM. This allows systems that have a verified and/or unchangeable
filesystem to enforce module and firmware loading restrictions without
needing to sign the files individually.
fs: define a string representation of the kernel_read_file_id enumeration
A string representation of the kernel_read_file_id enumeration is
needed for displaying messages (eg. pr_info, auditing) that can be
used by multiple LSMs and the integrity subsystem. To simplify
keeping the list of strings up to date with the enumeration, this
patch defines two new preprocessing macros named __fid_enumify and
__fid_stringify to create the enumeration and an array of strings.
kernel_read_file_id_str() returns a string based on the enumeration.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
[kees: removed removal of my old version, constified pointer values] Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.l.morris@oracle.com>
security_get_bool_value(int bool) argument "bool" conflicts with
in-kernel macros such as BUILD_BUG(). This patch changes this to
index which isn't a type.
Cc: Paul Moore <paul@paul-moore.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Eric Paris <eparis@parisplace.org> Cc: James Morris <james.l.morris@oracle.com> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Andrew Perepechko <anserper@ya.ru> Cc: Jeff Vander Stoep <jeffv@google.com> Cc: selinux@tycho.nsa.gov Cc: Eric Paris <eparis@redhat.com> Cc: Paul Moore <pmoore@redhat.com> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Prarit Bhargava <prarit@redhat.com> Acked-by: David Howells <dhowells@redhat.com>
[PM: wrapped description for checkpatch.pl, use "selinux:..." as subj] Signed-off-by: Paul Moore <paul@paul-moore.com>
David Howells [Tue, 12 Apr 2016 19:10:19 +0000 (20:10 +0100)]
Merge branch 'keys-sig' into keys-next
These commits do the following:
(1) Retain a signature in an asymmetric-type key and associate with it the
identifiers that will match a key that can be used to verify it.
(2) Differentiate an X.509 cert that cannot be used versus one that cannot
be verified due to unavailable crypto. This is noted in the
structures involved.
(3) Determination of the self-signedness of an X.509 cert is improved to
include checks on the subject/issuer names and the key
algorithm/signature algorithm types.
(4) Self-signed X.509 certificates are consistency checked early on if the
appropriate crypto is available.
Signed-off-by: David Howells <dhowells@redhat.com>
Mat Martineau [Tue, 12 Apr 2016 18:54:58 +0000 (19:54 +0100)]
KEYS: Add KEYCTL_DH_COMPUTE command
This adds userspace access to Diffie-Hellman computations through a
new keyctl() syscall command to calculate shared secrets or public
keys using input parameters stored in the keyring.
Input key ids are provided in a struct due to the current 5-arg limit
for the keyctl syscall. Only user keys are supported in order to avoid
exposing the content of logon or encrypted keys.
The output is written to the provided buffer, based on the assumption
that the values are only needed in userspace.
Future support for other types of key derivation would involve a new
command, like KEYCTL_ECDH_COMPUTE.
Once Diffie-Hellman support is included in the crypto API, this code
can be converted to use the crypto API to take advantage of possible
hardware acceleration and reduce redundant code.
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Tue, 12 Apr 2016 18:54:58 +0000 (19:54 +0100)]
KEYS: user_update should use copy of payload made during preparsing
The payload preparsing routine for user keys makes a copy of the payload
provided by the caller and stashes it in the key_preparsed_payload struct for
->instantiate() or ->update() to use. However, ->update() takes another copy
of this to attach to the keyring. ->update() should be using this directly
and clearing the pointer in the preparse data.
Signed-off-by: David Howells <dhowells@redhat.com>
Andreas Ziegler [Tue, 12 Apr 2016 18:54:58 +0000 (19:54 +0100)]
security: integrity: Remove select to deleted option PUBLIC_KEY_ALGO_RSA
Commit d43de6c780a8 ("akcipher: Move the RSA DER encoding check to
the crypto layer") removed the Kconfig option PUBLIC_KEY_ALGO_RSA,
but forgot to remove a 'select' to this option in the definition of
INTEGRITY_ASYMMETRIC_KEYS.
Let's remove the select, as it's ineffective now.
Signed-off-by: Andreas Ziegler <andreas.ziegler@fau.de> Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Thu, 7 Apr 2016 08:45:23 +0000 (09:45 +0100)]
IMA: Use the the system trusted keyrings instead of .ima_mok
Add a config option (IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY)
that, when enabled, allows keys to be added to the IMA keyrings by
userspace - with the restriction that each must be signed by a key in the
system trusted keyrings.
EPERM will be returned if this option is disabled, ENOKEY will be returned if
no authoritative key can be found and EKEYREJECTED will be returned if the
signature doesn't match. Other errors such as ENOPKG may also be returned.
If this new option is enabled, the builtin system keyring is searched, as is
the secondary system keyring if that is also enabled. Intermediate keys
between the builtin system keyring and the key being added can be added to
the secondary keyring (which replaces .ima_mok) to form a trust chain -
provided they are also validly signed by a key in one of the trusted keyrings.
The .ima_mok keyring is then removed and the IMA blacklist keyring gets its
own config option (IMA_BLACKLIST_KEYRING).
Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
David Howells [Wed, 6 Apr 2016 15:14:27 +0000 (16:14 +0100)]
certs: Add a secondary system keyring that can be added to dynamically
Add a secondary system keyring that can be added to by root whilst the
system is running - provided the key being added is vouched for by a key
built into the kernel or already added to the secondary keyring.
Rename .system_keyring to .builtin_trusted_keys to distinguish it more
obviously from the new keyring (called .secondary_trusted_keys).
The new keyring needs to be enabled with CONFIG_SECONDARY_TRUSTED_KEYRING.
If the secondary keyring is enabled, a link is created from that to
.builtin_trusted_keys so that the the latter will automatically be searched
too if the secondary keyring is searched.
Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Wed, 6 Apr 2016 15:14:26 +0000 (16:14 +0100)]
KEYS: Move the point of trust determination to __key_link()
Move the point at which a key is determined to be trustworthy to
__key_link() so that we use the contents of the keyring being linked in to
to determine whether the key being linked in is trusted or not.
What is 'trusted' then becomes a matter of what's in the keyring.
Currently, the test is done when the key is parsed, but given that at that
point we can only sensibly refer to the contents of the system trusted
keyring, we can only use that as the basis for working out the
trustworthiness of a new key.
With this change, a trusted keyring is a set of keys that once the
trusted-only flag is set cannot be added to except by verification through
one of the contained keys.
Further, adding a key into a trusted keyring, whilst it might grant
trustworthiness in the context of that keyring, does not automatically
grant trustworthiness in the context of a second keyring to which it could
be secondarily linked.
To accomplish this, the authentication data associated with the key source
must now be retained. For an X.509 cert, this means the contents of the
AuthorityKeyIdentifier and the signature data.
If system keyrings are disabled then restrict_link_by_builtin_trusted()
resolves to restrict_link_reject(). The integrity digital signature code
still works correctly with this as it was previously using
KEY_FLAG_TRUSTED_ONLY, which doesn't permit anything to be added if there
is no system keyring against which trust can be determined.
Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Wed, 6 Apr 2016 15:14:26 +0000 (16:14 +0100)]
KEYS: Make the system trusted keyring depend on the asymmetric key type
Make the system trusted keyring depend on the asymmetric key type as
there's not a lot of point having it if you can't then load asymmetric keys
onto it.
This requires the ASYMMETRIC_KEY_TYPE to be made a bool, not a tristate, as
the Kconfig language doesn't then correctly force ASYMMETRIC_KEY_TYPE to
'y' rather than 'm' if SYSTEM_TRUSTED_KEYRING is 'y'.
Making SYSTEM_TRUSTED_KEYRING *select* ASYMMETRIC_KEY_TYPE instead doesn't
work as the Kconfig interpreter then wrongly complains about dependency
loops.
Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Wed, 6 Apr 2016 15:14:25 +0000 (16:14 +0100)]
X.509: Use verify_signature() if we have a struct key * to use
We should call verify_signature() rather than directly calling
public_key_verify_signature() if we have a struct key to use as we
shouldn't be poking around in the private data of the key struct as that's
subtype dependent.
Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Wed, 6 Apr 2016 15:14:25 +0000 (16:14 +0100)]
KEYS: Generalise x509_request_asymmetric_key()
Generalise x509_request_asymmetric_key(). It doesn't really have any
dependencies on X.509 features as it uses generalised IDs and the
public_key structs that contain data extracted from X.509.
Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Wed, 6 Apr 2016 15:14:24 +0000 (16:14 +0100)]
KEYS: Add a facility to restrict new links into a keyring
Add a facility whereby proposed new links to be added to a keyring can be
vetted, permitting them to be rejected if necessary. This can be used to
block public keys from which the signature cannot be verified or for which
the signature verification fails. It could also be used to provide
blacklisting.
This affects operations like add_key(), KEYCTL_LINK and KEYCTL_INSTANTIATE.
To this end:
(1) A function pointer is added to the key struct that, if set, points to
the vetting function. This is called as:
int (*restrict_link)(struct key *keyring,
const struct key_type *key_type,
unsigned long key_flags,
const union key_payload *key_payload),
where 'keyring' will be the keyring being added to, key_type and
key_payload will describe the key being added and key_flags[*] can be
AND'ed with KEY_FLAG_TRUSTED.
[*] This parameter will be removed in a later patch when
KEY_FLAG_TRUSTED is removed.
The function should return 0 to allow the link to take place or an
error (typically -ENOKEY, -ENOPKG or -EKEYREJECTED) to reject the
link.
The pointer should not be set directly, but rather should be set
through keyring_alloc().
Note that if called during add_key(), preparse is called before this
method, but a key isn't actually allocated until after this function
is called.
(2) KEY_ALLOC_BYPASS_RESTRICTION is added. This can be passed to
key_create_or_update() or key_instantiate_and_link() to bypass the
restriction check.
(3) KEY_FLAG_TRUSTED_ONLY is removed. The entire contents of a keyring
with this restriction emplaced can be considered 'trustworthy' by
virtue of being in the keyring when that keyring is consulted.
(4) key_alloc() and keyring_alloc() take an extra argument that will be
used to set restrict_link in the new key. This ensures that the
pointer is set before the key is published, thus preventing a window
of unrestrictedness. Normally this argument will be NULL.
(5) As a temporary affair, keyring_restrict_trusted_only() is added. It
should be passed to keyring_alloc() as the extra argument instead of
setting KEY_FLAG_TRUSTED_ONLY on a keyring. This will be replaced in
a later patch with functions that look in the appropriate places for
authoritative keys.
Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Paolo Abeni [Fri, 8 Apr 2016 10:20:30 +0000 (12:20 +0200)]
security: drop the unused hook skb_owned_by
The skb_owned_by hook was added with the commit ca10b9e9a8ca
("selinux: add a skb_owned_by() hook") and later removed
when said commit was reverted.
Later on, when switching to list of hooks, a field named
'skb_owned_by' was included into the security_hook_head struct,
but without any users nor caller.
This commit removes the said left-over field.
Fixes: b1d9e6b0646d ("LSM: Switch to lists of hooks") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: Paul Moore <pmoore@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
David Howells [Wed, 6 Apr 2016 15:14:24 +0000 (16:14 +0100)]
PKCS#7: Make trust determination dependent on contents of trust keyring
Make the determination of the trustworthiness of a key dependent on whether
a key that can verify it is present in the supplied ring of trusted keys
rather than whether or not the verifying key has KEY_FLAG_TRUSTED set.
verify_pkcs7_signature() will return -ENOKEY if the PKCS#7 message trust
chain cannot be verified.
Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Wed, 6 Apr 2016 15:14:24 +0000 (16:14 +0100)]
KEYS: Generalise system_verify_data() to provide access to internal content
Generalise system_verify_data() to provide access to internal content
through a callback. This allows all the PKCS#7 stuff to be hidden inside
this function and removed from the PE file parser and the PKCS#7 test key.
If external content is not required, NULL should be passed as data to the
function. If the callback is not required, that can be set to NULL.
The function is now called verify_pkcs7_signature() to contrast with
verify_pefile_signature() and the definitions of both have been moved into
linux/verification.h along with the key_being_used_for enum.
Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Wed, 6 Apr 2016 15:13:34 +0000 (16:13 +0100)]
X.509: Fix self-signed determination
There's a bug in the code determining whether a certificate is self-signed
or not: if they have neither AKID nor SKID then we just assume that the
cert is self-signed, which may not be true.
Fix this by checking that the raw subject name matches the raw issuer name
and that the public key algorithm for the key and signature are both the
same in addition to requiring that the AKID bits match.
Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Wed, 6 Apr 2016 15:13:34 +0000 (16:13 +0100)]
X.509: Extract signature digest and make self-signed cert checks earlier
Extract the signature digest for an X.509 certificate earlier, at the end
of x509_cert_parse() rather than leaving it to the callers thereof since it
has to be called anyway.
Further, immediately after that, check the signature on self-signed
certificates, also rather in the callers of x509_cert_parse().
We note in the x509_certificate struct the following bits of information:
(1) Whether the signature is self-signed (even if we can't check the
signature due to missing crypto).
(2) Whether the key held in the certificate needs unsupported crypto to be
used. We may get a PKCS#7 message with X.509 certs that we can't make
use of - we just ignore them and give ENOPKG at the end it we couldn't
verify anything if at least one of these unusable certs are in the
chain of trust.
(3) Whether the signature held in the certificate needs unsupported crypto
to be checked. We can still use the key held in this certificate,
even if we can't check the signature on it - if it is held in the
system trusted keyring, for instance. We just can't add it to a ring
of trusted keys or follow it further up the chain of trust.
Making these checks earlier allows x509_check_signature() to be removed and
replaced with direct calls to public_key_verify_signature().
Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Wed, 6 Apr 2016 15:13:33 +0000 (16:13 +0100)]
PKCS#7: Make the signature a pointer rather than embedding it
Point to the public_key_signature struct from the pkcs7_signed_info struct
rather than embedding it. This makes the code consistent with the X.509
signature handling and makes it possible to have a common cleanup function.
We also save a copy of the digest in the signature without sharing the
memory with the crypto layer metadata.
Signed-off-by: David Howells <dhowells@redhat.com>
David Howells [Wed, 6 Apr 2016 15:13:33 +0000 (16:13 +0100)]
KEYS: Add identifier pointers to public_key_signature struct
Add key identifier pointers to public_key_signature struct so that they can
be used to retain the identifier of the key to be used to verify the
signature in both PKCS#7 and X.509.
Signed-off-by: David Howells <dhowells@redhat.com>
Utilize existing kernel_read_file hook on kernel module load.
Add module_load permission to the system class.
Enforces restrictions on kernel module origin when calling the
finit_module syscall. The hook checks that source type has
permission module_load for the target type.
Example for finit_module:
allow foo bar_file:system module_load;
Similarly restrictions are enforced on kernel module loading when
calling the init_module syscall. The hook checks that source
type has permission module_load with itself as the target object
because the kernel module is sourced from the calling process.
Example for init_module:
allow foo foo:system module_load;
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
[PM: fixed return value of selinux_kernel_read_file()] Signed-off-by: Paul Moore <paul@paul-moore.com>
Paul Moore [Mon, 28 Mar 2016 19:16:53 +0000 (15:16 -0400)]
selinux: simply inode label states to INVALID and INITIALIZED
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.
Janak Desai [Mon, 28 Mar 2016 15:09:46 +0000 (11:09 -0400)]
netlabel: fix a problem with netlbl_secattr_catmap_setrng()
We try to be clever and set large chunks of the bitmap at once, when
possible; unfortunately we weren't very clever when we wrote the code
and messed up the if-conditional. Fix this bug and restore proper
operation.
Signed-off-by: Janak Desai <Janak.Desai@gtri.gatech.edu> Signed-off-by: Paul Moore <paul@paul-moore.com>
Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core kernel fixes from Ingo Molnar:
"This contains the nohz/atomic cleanup/fix for the fetch_or() ugliness
you noted during the original nohz pull request, plus there's also
misc fixes:
- fix liblockdep build bug
- fix uapi header build bug
- print more lockdep hash collision info to help debug recent reports
of hash collisions
- update MAINTAINERS email address"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
MAINTAINERS: Update my email address
locking/lockdep: Print chain_key collision information
uapi/linux/stddef.h: Provide __always_inline to userspace headers
tools/lib/lockdep: Fix unsupported 'basename -s' in run_tests.sh
locking/atomic, sched: Unexport fetch_or()
timers/nohz: Convert tick dependency mask to atomic_t
locking/atomic: Introduce atomic_fetch_or()
Commit 840f5b0572ea ("media: au0828 disable tuner to demod link in
au0828_media_device_register()") removed all uses of the 'dtv_demod',
but left the variable itself around.
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
"This lot contains:
- Some fixups for the fallout of the topology consolidation which
unearthed AMD/Intel inconsistencies
- Documentation for the x86 topology management
- Support for AMD advanced power management bits
- Two simple cleanups removing duplicated code"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Add advanced power management bits
x86/thread_info: Merge two !__ASSEMBLY__ sections
x86/cpufreq: Remove duplicated TDP MSR macro definitions
x86/Documentation: Start documenting x86 topology
x86/cpu: Get rid of compute_unit_id
perf/x86/amd: Cleanup Fam10h NB event constraints
x86/topology: Fix AMD core count
Merge tag 'rproc-v4.6-rc1' of git://github.com/andersson/remoteproc
Pull remoteproc fix from Bjorn Andersson:
"Fix incorrect error check in the ST remoteproc driver and advertise
the newly created linux-remoteproc mailing list"
* tag 'rproc-v4.6-rc1' of git://github.com/andersson/remoteproc:
MAINTAINERS: Add mailing list for remote processor subsystems
remoteproc: st: fix check of syscon_regmap_lookup_by_phandle() return value
Pull SCSI target fixes from Nicholas Bellinger:
"This includes fixes from HCH for -rc1 configfs default_groups
conversion changes that ended up breaking some iscsi-target
default_groups, along with Sagi's ib_drain_qp() conversion for
iser-target to use the common caller now available to RDMA kernel
consumers in v4.6+ code"
* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
target: add a new add_wwn_groups fabrics method
target: initialize the nacl base CIT begfore init_nodeacl
target: remove ->fabric_cleanup_nodeacl
iser-target: Use ib_drain_qp
Convert straggling drivers to new six-argument get_user_pages()
Commit d4edcf0d5695 ("mm/gup: Switch all callers of get_user_pages() to
not pass tsk/mm") switched get_user_pages() callers to the simpler model
where they no longer pass in the thread and mm pointer. But since then
we've merged changes to a few drivers that re-introduce use of the old
interface. Let's fix them up.
They continued to work fine (thanks to the truly disgusting macros
introduced in commit cde70140fed8: "mm/gup: Overload get_user_pages()
functions"), but cause unnecessary build noise.
Merge tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
Pull clk fixes from Stephen Boyd:
"A handful of const updates for reset ops and a couple fixes to the
newly introduced IPQ4019 clock driver"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: qcom: ipq4019: add some fixed clocks for ddrppl and fepll
clk: qcom: ipq4019: switch remaining defines to enums
clk: qcom: Make reset_control_ops const
clk: tegra: Make reset_control_ops const
clk: sunxi: Make reset_control_ops const
clk: atlas7: Make reset_control_ops const
clk: rockchip: Make reset_control_ops const
clk: mmp: Make reset_control_ops const
clk: mediatek: Make reset_control_ops const
Merge tag 'pm+acpi-4.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management and ACPI fix from Rafael J. Wysocki:
"Just one fix for a nasty boot failure on some systems based on Intel
Skylake that shipped with broken firmware where enabling
hardware-coordinated P-states management (HWP) causes a faulty
interrupt handler in SMM to be invoked and crash the system (Srinivas
Pandruvada)"
* tag 'pm+acpi-4.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / processor: Request native thermal interrupt handling via _OSC
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
.mailmap: add Christophe Ricard
Make CONFIG_FHANDLE default y
mm/page_isolation.c: fix the function comments
oom, oom_reaper: do not enqueue task if it is on the oom_reaper_list head
mm/page_isolation: fix tracepoint to mirror check function behavior
mm/rmap: batched invalidations should use existing api
x86/mm: TLB_REMOTE_SEND_IPI should count pages
mm: fix invalid node in alloc_migrate_target()
include/linux/huge_mm.h: return NULL instead of false for pmd_trans_huge_lock()
mm, kasan: fix compilation for CONFIG_SLAB
MAINTAINERS: orangefs mailing list is subscribers-only
Merge branch 'for-linus-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
"This has a few fixes Dave Sterba had queued up. These are all pretty
small, but since they were tested I decided against waiting for more"
* 'for-linus-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: transaction_kthread() is not freezable
btrfs: cleaner_kthread() doesn't need explicit freeze
btrfs: do not write corrupted metadata blocks to disk
btrfs: csum_tree_block: return proper errno value
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
- fix oops when patching in alternative sequences on big-endian CPUs
- reconcile asm/perf_event.h after merge window fallout with KVM ARM
- defconfig updates
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: defconfig: updates for 4.6
arm64: perf: Move PMU register related defines to asm/perf_event.h
arm64: opcodes.h: Add arm big-endian config options before including arm header
Merge tag 'sound-4.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"A collection of small fixes:
- a fix in ALSA timer core to avoid possible BUG() trigger
- a fix in ALSA timer core 32bit compat layer
- a few HD-audio quirks for ASUS and HP machines
- AMD HD-audio HDMI controller quirks
- fixes of USB-audio double-free at some error paths
- a fix for memory leak in DICE driver at hotunplug"
* tag 'sound-4.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: timer: Use mod_timer() for rearming the system timer
ALSA: hda - fix front mic problem for a HP desktop
ALSA: usb-audio: Fix double-free in error paths after snd_usb_add_audio_stream() call
ALSA: hda: add AMD Polaris-10/11 AZ PCI IDs with proper driver caps
ALSA: dice: fix memory leak when unplugging
ALSA: hda - Apply fix for white noise on Asus N550JV, too
ALSA: hda - Fix white noise on Asus N750JV headphone
ALSA: hda - Asus N750JV external subwoofer fixup
ALSA: timer: fix gparams ioctl compatibility for different architectures
Newer Fedora and OpenSUSE didn't boot with my standard configuration.
It took me some time to figure out why, in fact I had to write a script
to try different config options systematically.
The problem is that something (systemd) in dracut depends on
CONFIG_FHANDLE, which adds open by file handle syscalls.
While it is set in defconfigs it is very easy to miss when updating
older configs because it is not default y.
Make it default y and also depend on EXPERT, as dracut use is likely
widespread.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Richard Weinberger <richard.weinberger@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Neil Zhang [Fri, 1 Apr 2016 21:31:37 +0000 (14:31 -0700)]
mm/page_isolation.c: fix the function comments
Commit fea85cff11de ("mm/page_isolation.c: return last tested pfn rather
than failure indicator") changed the meaning of the return value. Let's
change the function comments as well.
Signed-off-by: Neil Zhang <neilzhang1123@hotmail.com> Cc: Joonsoo Kim <js1304@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Fri, 1 Apr 2016 21:31:34 +0000 (14:31 -0700)]
oom, oom_reaper: do not enqueue task if it is on the oom_reaper_list head
Commit bb29902a7515 ("oom, oom_reaper: protect oom_reaper_list using
simpler way") has simplified the check for tasks already enqueued for
the oom reaper by checking tsk->oom_reaper_list != NULL. This check is
not sufficient because the tsk might be the head of the queue without
any other tasks queued and then we would simply lockup looping on the
same task. Fix the condition by checking for the head as well.
Fixes: bb29902a7515 ("oom, oom_reaper: protect oom_reaper_list using simpler way") Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lucas Stach [Fri, 1 Apr 2016 21:31:32 +0000 (14:31 -0700)]
mm/page_isolation: fix tracepoint to mirror check function behavior
Page isolation has not failed if the fin pfn extends beyond the end pfn
and test_pages_isolated checks this correctly. Fix the tracepoint to
report the same result as the actual check function.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Joonsoo Kim <js1304@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nadav Amit [Fri, 1 Apr 2016 21:31:26 +0000 (14:31 -0700)]
mm/rmap: batched invalidations should use existing api
The recently introduced batched invalidations mechanism uses its own
mechanism for shootdown. However, it does wrong accounting of
interrupts (e.g., inc_irq_stat is called for local invalidations),
trace-points (e.g., TLB_REMOTE_SHOOTDOWN for local invalidations) and
may break some platforms as it bypasses the invalidation mechanisms of
Xen and SGI UV.
This patch reuses the existing TLB flushing mechnaisms instead. We use
NULL as mm to indicate a global invalidation is required.
Fixes 72b252aed506b8 ("mm: send one IPI per CPU to TLB flush all entries after unmapping pages") Signed-off-by: Nadav Amit <namit@vmware.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nadav Amit [Fri, 1 Apr 2016 21:31:23 +0000 (14:31 -0700)]
x86/mm: TLB_REMOTE_SEND_IPI should count pages
TLB_REMOTE_SEND_IPI was recently introduced, but it counts bytes instead
of pages. In addition, it does not report correctly the case in which
flush_tlb_page flushes a page. Fix it to be consistent with other TLB
counters.
Fixes: 5b74283ab251b9d ("x86, mm: trace when an IPI is about to be sent") Signed-off-by: Nadav Amit <namit@vmware.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It is incorrect to use next_node to find a target node, it will return
MAX_NUMNODES or invalid node. This will lead to crash in buddy system
allocation.
Marcin Wojtas [Fri, 1 Apr 2016 13:21:18 +0000 (15:21 +0200)]
net: mvneta: fix changing MTU when using per-cpu processing
After enabling per-cpu processing it appeared that under heavy load
changing MTU can result in blocking all port's interrupts and
transmitting data is not possible after the change.
This commit fixes above issue by disabling percpu interrupts for the
time, when TXQs and RXQs are reconfigured.
Signed-off-by: Marcin Wojtas <mw@semihalf.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Initially the phy_bus_name was added to manipulate the
driver name but it was recently just used to manage the
fixed-link and then to take some decision at run-time.
So the patch uses the is_pseudo_fixed_link and removes
the phy_bus_name variable not necessary anymore.
The driver can manage the mdio registration by using phy-handle,
dwmac-mdio and own parameter e.g. snps,phy-addr.
This patch takes care about all these possible configurations
and fixes the mdio registration in case of there is a real
transceiver or a switch (that needs to be managed by using
fixed-link).
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com> Reviewed-by: Andreas Färber <afaerber@suse.de> Tested-by: Frank Schäfer <fschaefer.oss@googlemail.com> Cc: Gabriel Fernandez <gabriel.fernandez@linaro.org> Cc: Dinh Nguyen <dinh.linux@gmail.com> Cc: David S. Miller <davem@davemloft.net> Cc: Phil Reid <preid@electromag.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Revert "stmmac: Fix 'eth0: No PHY found' regression"
This reverts commit 88f8b1bb41c6208f81b6a480244533ded7b59493.
due to problems on GeekBox and Banana Pi M1 board when
connected to a real transceiver instead of a switch via
fixed-link.
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com> Cc: Gabriel Fernandez <gabriel.fernandez@linaro.org> Cc: Andreas Färber <afaerber@suse.de> Cc: Frank Schäfer <fschaefer.oss@googlemail.com> Cc: Dinh Nguyen <dinh.linux@gmail.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixs a regression raised when test on chips that use
the normal descriptor layout. In fact, no len bits were set for
the TDES1 and no OWN bit inside the TDES0.
Signed-off-by: Giuseppe CAVALLARO <peppe.cavallaro@st.com> Tested-by: Andreas Färber <afaerber@suse.de> Cc: Fabrice Gasnier <fabrice.gasnier@st.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Same can be triggered with PROVE_RCU (+ PROVE_RCU_REPEATEDLY) enabled
from tun_attach_filter() when user space calls ioctl(tun_fd, TUN{ATTACH,
DETACH}FILTER, ...) for adding/removing a BPF filter on tap devices.
Since the fix in f91ff5b9ff52 ("net: sk_{detach|attach}_filter() rcu
fixes") sk_attach_filter()/sk_detach_filter() now dereferences the
filter with rcu_dereference_protected(), checking whether socket lock
is held in control path.
Since its introduction in 994051625981 ("tun: socket filter support"),
tap filters are managed under RTNL lock from __tun_chr_ioctl(). Thus the
sock_owned_by_user(sk) doesn't apply in this specific case and therefore
triggers the false positive.
Extend the BPF API with __sk_attach_filter()/__sk_detach_filter() pair
that is used by tap filters and pass in lockdep_rtnl_is_held() for the
rcu_dereference_protected() checks instead.
Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"Nothing too crazy in here: a bunch of AMD fixes/quirks, two msm fixes,
some rockchip fixes, and a udl warning fix, along with one locking fix
for displayport that seems to fix some dodgy monitors"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/udl: Use unlocked gem unreferencing
drm/dp: move hw_mutex up the call stack
drm/amdgpu: Don't move pinned BOs
drm/radeon: Don't move pinned BOs
drm/radeon: add a dpm quirk for all R7 370 parts
drm/radeon: add another R7 370 quirk
drm/rockchip: dw_hdmi: Don't call platform_set_drvdata()
drm/rockchip: vop: Fix vop crtc cleanup
drm/rockchip: dw_hdmi: Call drm_encoder_cleanup() in error path
drm/rockchip: vop: Disable planes when disabling CRTC
drm/rockchip: vop: Don't reject empty modesets
drm/rockchip: cancel pending vblanks on close
drm/rockchip: vop: fix crtc size in plane check
drm/radeon: add a dpm quirk for sapphire Dual-X R7 370 2G D5
drm/amd: Beef up ACP Kconfig menu text
drm/msm: fix typo in the !COMMON_CLK case
drm/msm: fix bug after preclose removal
Merge tag 'powerpc-4.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
- Fixup preempt underflow with huge pages from Sebastian Siewior
- Fix altivec SPR not being saved from Oliver O'Halloran
- Correct used_vsr comment from Simon Guo
* tag 'powerpc-4.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc: Correct used_vsr comment
powerpc/process: Fix altivec SPR not being saved
powerpc/mm: Fixup preempt underflow with huge pages