Commit Graph

34 Commits

Author SHA1 Message Date
Michal Hocko a7c3e901a4 mm: introduce kv[mz]alloc helpers
Patch series "kvmalloc", v5.

There are many open coded kmalloc with vmalloc fallback instances in the
tree.  Most of them are not careful enough or simply do not care about
the underlying semantic of the kmalloc/page allocator which means that
a) some vmalloc fallbacks are basically unreachable because the kmalloc
part will keep retrying until it succeeds b) the page allocator can
invoke a really disruptive steps like the OOM killer to move forward
which doesn't sound appropriate when we consider that the vmalloc
fallback is available.

As it can be seen implementing kvmalloc requires quite an intimate
knowledge if the page allocator and the memory reclaim internals which
strongly suggests that a helper should be implemented in the memory
subsystem proper.

Most callers, I could find, have been converted to use the helper
instead.  This is patch 6.  There are some more relying on __GFP_REPEAT
in the networking stack which I have converted as well and Eric Dumazet
was not opposed [2] to convert them as well.

[1] http://lkml.kernel.org/r/20170130094940.13546-1-mhocko@kernel.org
[2] http://lkml.kernel.org/r/1485273626.16328.301.camel@edumazet-glaptop3.roam.corp.google.com

This patch (of 9):

Using kmalloc with the vmalloc fallback for larger allocations is a
common pattern in the kernel code.  Yet we do not have any common helper
for that and so users have invented their own helpers.  Some of them are
really creative when doing so.  Let's just add kv[mz]alloc and make sure
it is implemented properly.  This implementation makes sure to not make
a large memory pressure for > PAGE_SZE requests (__GFP_NORETRY) and also
to not warn about allocation failures.  This also rules out the OOM
killer as the vmalloc is a more approapriate fallback than a disruptive
user visible action.

This patch also changes some existing users and removes helpers which
are specific for them.  In some cases this is not possible (e.g.
ext4_kvmalloc, libcfs_kvzalloc) because those seems to be broken and
require GFP_NO{FS,IO} context which is not vmalloc compatible in general
(note that the page table allocation is GFP_KERNEL).  Those need to be
fixed separately.

While we are at it, document that __vmalloc{_node} about unsupported gfp
mask because there seems to be a lot of confusion out there.
kvmalloc_node will warn about GFP_KERNEL incompatible (which are not
superset) flags to catch new abusers.  Existing ones would have to die
slowly.

[sfr@canb.auug.org.au: f2fs fixup]
  Link: http://lkml.kernel.org/r/20170320163735.332e64b7@canb.auug.org.au
Link: http://lkml.kernel.org/r/20170306103032.2540-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>	[ext4 part]
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:12 -07:00
John Johansen 2c17cd3681 apparmor: fix restricted endian type warnings for policy unpack
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:55 -08:00
William Hua e025be0f26 apparmor: support querying extended trusted helper extra data
Allow a profile to carry extra data that can be queried via userspace.
This provides a means to store extra data in a profile that a trusted
helper can extract and use from live policy.

Signed-off-by: William Hua <william.hua@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:51 -08:00
John Johansen 31f75bfecd apparmor: make computing policy hashes conditional on kernel parameter
Allow turning off the computation of the policy hashes via the
apparmor.hash_policy kernel parameter.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:50 -08:00
John Johansen ef88a7ac55 apparmor: change aad apparmor_audit_data macro to a fn macro
The aad macro can replace aad strings when it is not intended to. Switch
to a fn macro so it is only applied when intended.

Also at the same time cleanup audit_data initialization by putting
common boiler plate behind a macro, and dropping the gfp_t parameter
which will become useless.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:47 -08:00
John Johansen 04dc715e24 apparmor: audit policy ns specified in policy load
Verify that profiles in a load set specify the same policy ns and
audit the name of the policy ns that policy is being loaded for.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:43 -08:00
John Johansen 5ac8c355ae apparmor: allow introspecting the loaded policy pre internal transform
Store loaded policy and allow introspecting it through apparmorfs. This
has several uses from debugging, policy validation, and policy checkpoint
and restore for containers.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:42 -08:00
John Johansen 11c236b89d apparmor: add a default null dfa
Instead of testing whether a given dfa exists in every code path, have
a default null dfa that is used when loaded policy doesn't provide a
dfa.

This will let us get rid of special casing and avoid dereference bugs
when special casing is missed.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:34 -08:00
John Johansen 6604d4c1c1 apparmor: allow policydb to be used as the file dfa
Newer policy will combine the file and policydb dfas, allowing for
better optimizations. However to support older policy we need to
keep the ability to address the "file" dfa separately. So dup
the policydb as if it is the file dfa and set the appropriate start
state.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:33 -08:00
John Johansen 474d6b7510 apparmor: prepare to support newer versions of policy
Newer policy encodes more than just version in the version tag,
so add masking to make sure the comparison remains correct.

Note: this is fully compatible with older policy as it will never set
the bits being masked out.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:32 -08:00
John Johansen 5ebfb12822 apparmor: add support for force complain flag to support learning mode
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:31 -08:00
John Johansen abbf873403 apparmor: remove paranoid load switch
Policy should always under go a full paranoid verification.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:30 -08:00
John Johansen 30b026a8d1 apparmor: pass gfp_t parameter into profile allocation
Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-01-16 01:18:29 -08:00
Arnd Bergmann 7616ac70d1 apparmor: fix SECURITY_APPARMOR_HASH_DEFAULT parameter handling
The newly added Kconfig option could never work and just causes a build error
when disabled:

security/apparmor/lsm.c:675:25: error: 'CONFIG_SECURITY_APPARMOR_HASH_DEFAULT' undeclared here (not in a function)
 bool aa_g_hash_policy = CONFIG_SECURITY_APPARMOR_HASH_DEFAULT;

The problem is that the macro undefined in this case, and we need to use the IS_ENABLED()
helper to turn it into a boolean constant.

Another minor problem with the original patch is that the option is even offered
in sysfs when SECURITY_APPARMOR_HASH is not enabled, so this also hides the option
in that case.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 6059f71f1e ("apparmor: add parameter to control whether policy hashing is used")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2016-07-27 17:39:26 +10:00
John Johansen 5f20fdfed1 apparmor: fix oops in profile_unpack() when policy_db is not present
BugLink: http://bugs.launchpad.net/bugs/1592547

If unpack_dfa() returns NULL due to the dfa not being present,
profile_unpack() is not checking if the dfa is not present (NULL).

Signed-off-by: John Johansen <john.johansen@canonical.com>
2016-07-12 08:43:10 -07:00
John Johansen 23ca7b640b apparmor: check that xindex is in trans_table bounds
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2016-07-12 08:43:10 -07:00
John Johansen 6059f71f1e apparmor: add parameter to control whether policy hashing is used
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2016-07-12 08:43:10 -07:00
John Johansen f8eb8a1324 apparmor: add the ability to report a sha1 hash of loaded policy
Provide userspace the ability to introspect a sha1 hash value for each
profile currently loaded.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2013-08-14 11:42:08 -07:00
John Johansen 556d0be74b apparmor: add an optional profile attachment string for profiles
Add the ability to take in and report a human readable profile attachment
string for profiles so that attachment specifications can be easily
inspected.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2013-08-14 11:42:07 -07:00
John Johansen 038165070a apparmor: allow setting any profile into the unconfined state
Allow emulating the default profile behavior from boot, by allowing
loading of a profile in the unconfined state into a new NS.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2013-08-14 11:42:07 -07:00
John Johansen 8651e1d657 apparmor: make free_profile available outside of policy.c
Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-08-14 11:42:06 -07:00
John Johansen dd51c84857 apparmor: provide base for multiple profiles to be replaced at once
previously profiles had to be loaded one at a time, which could result
in cases where a replacement of a set would partially succeed, and then fail
resulting in inconsistent policy.

Allow multiple profiles to replaced "atomically" so that the replacement
either succeeds or fails for the entire set of profiles.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2013-08-14 11:42:06 -07:00
John Johansen a4987857d2 apparmor: remove sid from profiles
The sid is not going to be a direct property of a profile anymore, instead
it will be directly related to the label, and the profile will pickup
a label back reference.

For null-profiles replace the use of sid with a per namespace unique
id.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
2013-04-28 00:37:13 -07:00
John Johansen 180a6f5965 apparmor: move perm defines into policy_unpack
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Steve Beattie <sbeattie@ubuntu.com>
2013-04-28 00:37:04 -07:00
Eric Paris 50c205f5e5 LSM: do not initialize common_audit_data to 0
It isn't needed.  If you don't set the type of the data associated with
that type it is a pretty obvious programming bug.  So why waste the cycles?

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:04 -04:00
Eric Paris bd5e50f9c1 LSM: remove the COMMON_AUDIT_DATA_INIT type expansion
Just open code it so grep on the source code works better.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:01 -04:00
Eric Paris 3b3b0e4fc1 LSM: shrink sizeof LSM specific portion of common_audit_data
Linus found that the gigantic size of the common audit data caused a big
perf hit on something as simple as running stat() in a loop.  This patch
requires LSMs to declare the LSM specific portion separately rather than
doing it in a union.  Thus each LSM can be responsible for shrinking their
portion and don't have to pay a penalty just because other LSMs have a
bigger space requirement.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-03 09:48:40 -07:00
John Johansen ad5ff3db53 AppArmor: Add ability to load extended policy
Add the base support for the new policy extensions. This does not bring
any additional functionality, or change current semantics.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
2012-03-14 19:09:03 -07:00
John Johansen b1b4bc2ed9 AppArmor: Fix oops in policy unpack auditing
Post unpacking of policy a verification pass is made on x transition
indexes.  When this fails a call to audit_iface is made resulting in an
oops, because audit_iface is expecting a valid buffer position but
since the failure comes from post unpack verification there is none.

Make the position argument optional so that audit_iface can be called
from post unpack verification.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2012-03-14 06:15:02 -07:00
John Johansen cdbd2884df AppArmor: Add mising end of structure test to caps unpacking
The unpacking of struct capsx is missing a check for the end of the
caps structure.  This can lead to unpack failures depending on what else
is packed into the policy file being unpacked.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
2012-02-27 11:38:20 -08:00
James Morris 7ee95850ba apparmor: sparse fix: rename shadowed variables in policy_unpack.c
Fix the following warnings:

security/apparmor/policy_unpack.c:384:35: warning: symbol 'size' shadows an earlier one
security/apparmor/policy_unpack.c:370:24: originally declared here
security/apparmor/policy_unpack.c:443:29: warning: symbol 'tmp' shadows an earlier one
security/apparmor/policy_unpack.c:434:21: originally declared here

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: John Johansen <john.johansen@canonical.com>
2011-09-09 16:56:28 -07:00
Randy Dunlap d410fa4ef9 Create Documentation/security/,
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>.
2011-05-19 15:59:38 -07:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
John Johansen 736ec752d9 AppArmor: policy routines for loading and unpacking policy
AppArmor policy is loaded in a platform independent flattened binary
stream.  Verify and unpack the data converting it to the internal
format needed for enforcement.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02 15:38:36 +10:00