apparmor: switch SECURITY_APPARMOR_HASH from sha1 to sha256

sha1 is insecure and has colisions, thus it is not useful for even
lightweight policy hash checks. Switch to sha256, which on modern
hardware is fast enough.

Separately as per NIST Policy on Hash Functions, sha1 usage must be
withdrawn by 2030. This config option currently is one of many that
holds up sha1 usage.

Signed-off-by: Dimitri John Ledkov <dimitri.ledkov@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmorfs: don't duplicate kfree_link()

rawdata_link_cb() is identical to it

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

apparmor: Fix move_mount mediation by detecting if source is detached

Prevent move_mount from applying the attach_disconnected flag
to move_mount(). This prevents detached mounts from appearing
as / when applying mount mediation, which is not only incorrect
but could result in bad policy being generated.

Basic mount rules like
allow mount,
allow mount options=(move) -> /target/,

will allow detached mounts, allowing older policy to continue
to function. New policy gains the ability to specify `detached` as
a source option
allow mount detached -> /target/,

In addition make sure support of move_mount is advertised as
a feature to userspace so that applications that generate policy
can respond to the addition.

Note: this fixes mediation of move_mount when a detached mount is used,
it does not fix the broader regression of apparmor mediation of
mounts under the new mount api.

Link: https://lore.kernel.org/all/68c166b8-5b4d-4612-8042-1dee3334385b@leemhuis.info/T/#mb35fdde37f999f08f0b02d58dc1bf4e6b65b8da2
Fixes: 157a3537d6bc ("apparmor: Fix regression in mount mediation")
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add io_uring mediation

For now, the io_uring mediation is limited to sqpoll and
override_creds.

Signed-off-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add user namespace creation mediation

Unprivileged user namespace creation is often used as a first step
in privilege escalation attacks. Instead of disabling it at the
sysrq level, which blocks its legitimate use as for setting up a sandbox,
allow control on a per domain basis.

This allows an admin to quickly lock down a system while also still
allowing legitimate use.

Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: allow restricting unprivileged change_profile

unprivileged unconfined can use change_profile to alter the confinement
set by the mac admin.

Allow restricting unprivileged unconfined by still allowing change_profile
but stacking the change against unconfined. This allows unconfined to
still apply system policy but allows the task to enter the new confinement.

If unprivileged unconfined is required a sysctl is provided to switch
to the previous behavior.

Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: advertise disconnected.path is available

While disconnected.path has been available for a while it was never
properly advertised as a feature. Fix this so that userspace doesn't
need special casing to handle it.

Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: refcount the pdb

With the move to permission tables the dfa is no longer a stand
alone entity when used, needing a minimum of a permission table.
However it still could be shared among different pdbs each using
a different permission table.

Instead of duping the permission table when sharing a pdb, add a
refcount to the pdb so it can be easily shared.

Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: pass cred through to audit info.

The cred is needed to properly audit some messages, and will be needed
in the future for uid conditional mediation. So pass it through to
where the apparmor_audit_data struct gets defined.

Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: remove unneeded #ifdef in decompress_zstd()

The whole function is guarded by CONFIG_SECURITY_APPARMOR_EXPORT_BINARY,
so the #ifdef here is redundant, remove it.

Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: advertise availability of exended perms

Userspace won't load policy using extended perms unless it knows the
kernel can handle them. Advertise that extended perms are supported in
the feature set.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Jon Tourville <jontourville@me.com>

apparmor: convert to new timestamp accessors

Convert to using the new inode timestamp accessor functions.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20231004185347.80880-82-jlayton@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

apparmor: convert to ctime accessor functions

In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-87-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

apparmor: update ctime whenever the mtime changes on an inode

In general, when updating the mtime on an inode, one must also update
the ctime. Add the missing ctime updates.

Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-5-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: port ->mkdir() to pass mnt_idmap

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>

apparmor: Fix decompression of rawdata for read back to userspace

The rawdata readback has a few of problems. First if compression is
enabled when the data is read then the compressed data is read out
instead decompressing the data. Second if compression of the data
fails, the code does not handle holding onto the raw_data in
uncompressed form. Third if the compression is enabled/disabled after
the rawdata was loaded, the check against the global control of
whether to use compression does not reflect what was already done to
the data.

Fix these by always storing the compressed size, along with the
original data size even if compression fails or is not used. And use
this to detect whether the rawdata is actually compressed.

Fixes: 52ccc20c652b ("apparmor: use zstd compression for profile data")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Jon Tourville <jon.tourville@canonical.com>

apparmor: Fix undefined references to zstd_ symbols

Unfortunately the switch to using zstd compression did not properly
ifdef all the code that uses zstd_ symbols. So that if exporting of
binary policy is disabled in the config the compile will fail with the
following errors

security/apparmor/lsm.c:1545: undefined reference to `zstd_min_clevel'
aarch64-linux-ld: security/apparmor/lsm.c:1545: undefined reference to `zstd_max_clevel'

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 52ccc20c652b ("apparmor: use zstd compression for profile data")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Jon Tourville <jon.tourville@canonical.com>

apparmor: make sure the decompression ctx is promperly initialized

The decompress ctx was not properly initialized when reading raw
profile data back to userspace.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 52ccc20c652b ("apparmor: use zstd compression for profile data")
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: rework profile->rules to be a list

Convert profile->rules to a list as the next step towards supporting
multiple rulesets in a profile. For this step only support a single
list entry item. The logic for iterating the list will come as a
separate step.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: refactor profile rules and attachments

In preparation for moving from a single set of rules and a single
attachment to multiple rulesets and attachments separate from the
profile refactor attachment information and ruleset info into their
own structures.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: preparse for state being more than just an integer

Convert from an unsigned int to a state_t for state position. This is
a step in prepping for the state position carrying some additional
flags, and a limited form of backtracking to support variables.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: convert policy lookup to use accept as an index

Remap polidydb dfa accept table from embedded perms to an index, and
then move the perm lookup to use the accept entry as an index into the
perm table. This is done so that the perm table can be separated from
the dfa, allowing dfa accept to index to share expanded permission
sets.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: convert xmatch to using the new shared policydb struct

continue permission unification by converting xmatch to use the
policydb struct that is used by the other profile dfas.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: combine file_rules and aa_policydb into a single shared struct

file_rules and policydb are almost the same and will need the same
features in the future so combine them.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: compute policydb permission on profile load

Rather than computing policydb permissions for each access
permissions can be computed once on profile load and stored for lookup.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: compute file permissions on profile load

Rather than computing file permissions for each file access, file
permissions can be computed once on profile load and stored for lookup.

Signed-off-by: Mike Salvatore <mike.salvatore@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: expose compression level limits in sysfs

Create two new files in apparmor's sysfs:

/sys/kernel/security/apparmor/raw_data_compression_level_min
/sys/kernel/security/apparmor/raw_data_compression_level_max

These correspond to the minimum and maximum zstd compression levels
that can be assigned to the apparmor module parameter
raw_data_compression_level.

Signed-off-by: Jon Tourville <jon.tourville@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: use zstd compression for profile data

Change the algorithm used by apparmor to compress profile data from
zlib to zstd, using the new zstd API introduced in 5.16.

Zstd provides a larger range of compression levels than zlib and
significantly better performance at the default level (for a relatively
small increase in compressed size).

The apparmor module parameter raw_data_compression_level is now clamped
to the minimum and maximum compression levels reported by the zstd
library. A compression level of 0 retains the previous behavior of
disabling policy compression instead of using zstd's behavior, which is
to use the default compression level.

Signed-off-by: Jon Tourville <jon.tourville@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix a memleak in multi_transaction_new()

In multi_transaction_new(), the variable t is not freed or passed out
on the failure of copy_from_user(t->data, buf, size), which could lead
to a memleak.

Fix this bug by adding a put_multi_transaction(t) in the error path.

Fixes: 1dea3b41e84c5 ("apparmor: speed up transactional queries")
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: move ptrace mediation to more logical task.{h,c}

AppArmor split out task oriented controls to their own logical file
a while ago. Ptrace mediation is better grouped with task than
ipc, so move it.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: extend policydb permission set by making use of the xbits

The policydb permission set has left the xbits unused. Make them available
for mediation.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: Fix memleak in aa_simple_write_to_buffer()

When copy_from_user failed, the memory is freed by kvfree. however the
management struct and data blob are allocated independently, so only
kvfree(data) cause a memleak issue here. Use aa_put_loaddata(data) to
fix this issue.

Fixes: a6a52579e52b5 ("apparmor: split load data into management struct and data blob")
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: Fix undefined reference to `zlib_deflate_workspacesize'

IF CONFIG_SECURITY_APPARMOR_EXPORT_BINARY is disabled, there remains
some unneed references to zlib, and can result in undefined symbol
references if ZLIB_INFLATE or ZLIB_DEFLATE are not defined.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: abfb9c0725f2 ("apparmor: make export of raw binary profile to userspace optional")
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: Fix some kernel-doc comments

Don't use /** for non-kernel-doc comments and change function name
aa_mangle_name to mangle_name in kernel-doc comment to Remove some
warnings found by running scripts/kernel-doc, which is caused by
using 'make W=1'.

security/apparmor/apparmorfs.c:1503: warning: Cannot understand *
on line 1503 - I thought it was a doc line
security/apparmor/apparmorfs.c:1530: warning: Cannot understand *
on line 1530 - I thought it was a doc line
security/apparmor/apparmorfs.c:1892: warning: Cannot understand *
on line 1892 - I thought it was a doc line
security/apparmor/apparmorfs.c:108: warning: expecting prototype for
aa_mangle_name(). Prototype was for mangle_name() instead

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: don't create raw_sha1 symlink if sha1 hashing is disabled

Currently if sha1 hashing of policy is disabled a sha1 hash symlink
to the non-existent file is created. There is now reason to create
the symlink in this case so don't do it.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: make export of raw binary profile to userspace optional

Embedded systems have limited space and don't need the introspection
or checkpoint restore capability provided by exporting the raw
profile binary data so make it so make it a config option.

This will reduce run time memory use and also speed up policy loads.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: use per file locks for transactional queries

As made mention of in commit 1dea3b41e84c5 ("apparmor: speed up
transactional queries"), a single lock is currently used to synchronize
transactional queries. We can, use the lock allocated for each file by
VFS instead.

Signed-off-by: Hamza Mahfooz <someguy@effective-light.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix doc warning

Fix gcc W=1 warning:

security/apparmor/apparmorfs.c:2125: warning: Function parameter or member 'p' not described in '__next_profile'

Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: update policy capable checks to use a label

Previously the policy capable checks assumed they were using the
current task. Make them take the task label so the query can be
made against an arbitrary task.

Signed-off-by: John Johansen <john.johansen@canonical.com>

fs: make helpers idmap mount aware

Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.

As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.

Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

apparmor: remove duplicate macro list_entry_is_head()

Strangely I hadn't had noticed the existence of the list_entry_is_head()
in apparmor code when added the same one in the list.h. Luckily it's
fully identical and didn't break builds. In any case we don't need a
duplicate anymore, thus remove it from apparmor code.

Link: https://lkml.kernel.org/r/20201208100639.88182-1-andriy.shevchenko@linux.intel.com
Fixes: e130816164e244 ("include/linux/list.h: add a macro to test if entry is pointing to the head")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E . Hallyn " <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

apparmor: Fix aa_label refcnt leak in policy_update

policy_update() invokes begin_current_label_crit_section(), which
returns a reference of the updated aa_label object to "label" with
increased refcount.

When policy_update() returns, "label" becomes invalid, so the refcount
should be decreased to keep refcount balanced.

The reference counting issue happens in one exception handling path of
policy_update(). When aa_may_manage_policy() returns not NULL, the
refcnt increased by begin_current_label_crit_section() is not decreased,
causing a refcnt leak.

Fix this issue by jumping to "end_section" label when
aa_may_manage_policy() returns not NULL.

Fixes: 5ac8c355ae00 ("apparmor: allow introspecting the loaded policy pre internal transform")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: Replace zero-length array with flexible-array

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
int stuff;
struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add outofband transition and use it in xattr match

There are cases where the a special out of band transition that can
not be triggered by input is useful in separating match conditions
in the dfa encoding.

The null_transition is currently used as an out of band transition
for match conditions that can not contain a \0 in their input
but apparmor needs an out of band transition for cases where
the match condition is allowed to contain any input character.

Achieve this by allowing for an explicit transition out of input
range that can only be triggered by code.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: remove useless aafs_create_symlink

commit 1180b4c757aa ("apparmor: fix dangling symlinks to policy
rawdata after replacement") reworked how the rawdata symlink is
handled but failedto remove aafs_create_symlink which was reduced to a
useles stub.

Fixes: 1180b4c757aa ("apparmor: fix dangling symlinks to policy rawdata after replacement")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix aa_xattrs_match() may sleep while holding a RCU lock

aa_xattrs_match() is unfortunately calling vfs_getxattr_alloc() from a
context protected by an rcu_read_lock. This can not be done as
vfs_getxattr_alloc() may sleep regardles of the gfp_t value being
passed to it.

Fix this by breaking the rcu_read_lock on the policy search when the
xattr match feature is requested and restarting the search if a policy
changes occur.

Fixes: 8e51f9087f40 ("apparmor: Add support for attaching profiles via xattr, presence and value")
Reported-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: John Johansen <john.johansen@canonical.com>

namei: allow nd_jump_link() to produce errors

In preparation for LOOKUP_NO_MAGICLINKS, it's necessary to add the
ability for nd_jump_link() to return an error which the corresponding
get_link() caller must propogate back up to the VFS.

Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

vfs: Convert apparmorfs to use the new mount API

Convert the apparmorfs filesystem to the new internal mount API as the old
one will be obsoleted and removed. This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: John Johansen <john.johansen@canonical.com>
cc: apparmor@lists.ubuntu.com
cc: linux-security-module@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2 of the license

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 315 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

apparmor: switch to ->free_inode()

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

apparmor: Initial implementation of raw policy blob compression

This adds an initial implementation of raw policy blob compression,
using deflate. Compression level can be controlled via a new sysctl,
"apparmor.rawdata_compression_level", which can be set to a value
between 0 (no compression) and 9 (highest compression).

Signed-off-by: Chris Coulson <chris.coulson@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmorfs: fix use-after-free on symlink traversal

symlink body shouldn't be freed without an RCU delay. Switch apparmorfs
to ->destroy_inode() and use of call_rcu(); free both the inode and symlink
body in the callback.

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

apparmor: delete the dentry in aafs_remove() to avoid a leak

Although the apparmorfs dentries are always dropped from the dentry cache
when the usage count drops to zero, there is no guarantee that this will
happen in aafs_remove(), as another thread might still be using it. In
this scenario, this means that the dentry will temporarily continue to
appear in the results of lookups, even after the call to aafs_remove().

In the case of removal of a profile - it also causes simple_rmdir()
on the profile directory to fail, as the directory won't be empty until
the usage counts of all child dentries have decreased to zero. This
results in the dentry for the profile directory leaking and appearing
empty in the file system tree forever.

Signed-off-by: Chris Coulson <chris.coulson@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

security: audit and remove any unnecessary uses of module.h

Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends. That changed
when we forked out support for the latter into the export.h file.
This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.

The advantage in removing such instances is that module.h itself
sources about 15 other headers; adding significantly to what we feed
cpp, and it can obscure what headers we are effectively using.

Since module.h might have been the implicit source for init.h
(for __init) and for export.h (for EXPORT_SYMBOL) we consider each
instance for the presence of either and replace as needed.

Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: linux-security-module@vger.kernel.org
Cc: linux-integrity@vger.kernel.org
Cc: keyrings@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: James Morris <james.morris@microsoft.com>

apparmor: clean an indentation issue, remove extraneous space

Trivial fix to clean up an indentation issue, remove space

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: Fully initialize aa_perms struct when answering userspace query

Fully initialize the aa_perms struct in profile_query_cb() to avoid the
potential of using an uninitialized struct member's value in a response
to a query from userspace.

Detected by CoverityScan CID#1415126 ("Uninitialized scalar variable")

Fixes: 4f3b3f2d79a4 ("apparmor: add profile permission query ability")
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix memory leak on buffer on error exit path

Currently on the error exit path the allocated buffer is not free'd
causing a memory leak. Fix this by kfree'ing it.

Detected by CoverityScan, CID#1466876 ("Resource leaks")

Fixes: 1180b4c757aa ("apparmor: fix dangling symlinks to policy rawdata after replacement")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix dangling symlinks to policy rawdata after replacement

When policy replacement occurs the symlinks in the profile directory
need to be updated to point to the new rawdata, otherwise once the
old rawdata is removed the symlink becomes broken.

Fix this by dynamically generating the symlink everytime it is read.
These links are used enough that their value needs to be cached and
this way we can avoid needing locking to read and update the link
value.

Fixes: a481f4d917835 ("apparmor: add custom apparmorfs that will be used by policy namespace files")
BugLink: http://bugs.launchpad.net/bugs/1755563
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: remove POLICY_MEDIATES_SAFE

The unpack code now makes sure every profile has a dfa so the safe
version of POLICY_MEDIATES is no longer needed.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add base infastructure for socket mediation

version 2 - Force an abi break. Network mediation will only be
available in v8 abi complaint policy.

Provide a basic mediation of sockets. This is not a full net mediation
but just whether a spcific family of socket can be used by an
application, along with setting up some basic infrastructure for
network mediation to follow.

the user space rule hav the basic form of
NETWORK RULE = [ QUALIFIERS ] 'network' [ DOMAIN ]
[ TYPE | PROTOCOL ]

DOMAIN = ( 'inet' | 'ax25' | 'ipx' | 'appletalk' | 'netrom' |
'bridge' | 'atmpvc' | 'x25' | 'inet6' | 'rose' |
'netbeui' | 'security' | 'key' | 'packet' | 'ash' |
'econet' | 'atmsvc' | 'sna' | 'irda' | 'pppox' |
'wanpipe' | 'bluetooth' | 'netlink' | 'unix' | 'rds' |
'llc' | 'can' | 'tipc' | 'iucv' | 'rxrpc' | 'isdn' |
'phonet' | 'ieee802154' | 'caif' | 'alg' | 'nfc' |
'vsock' | 'mpls' | 'ib' | 'kcm' ) ','

TYPE = ( 'stream' | 'dgram' | 'seqpacket' | 'rdm' | 'raw' |
'packet' )

PROTOCOL = ( 'tcp' | 'udp' | 'icmp' )

eg.
network,
network inet,

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

vfs: do bulk POLL* -> EPOLL* replacement

This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do. But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

apparmor: improve overlapping domain attachment resolution

Overlapping domain attachments using the current longest left exact
match fail in some simple cases, and with the fix to ensure consistent
behavior by failing unresolvable attachments it becomes important to
do a better job.

eg. under the current match the following are unresolvable where
the alternation is clearly a better match under the most specific
left match rule.
/**
/{bin/,}usr/

Use a counting match that detects when a loop in the state machine is
enter, and return the match count to provide a better specific left
match resolution.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: convert attaching profiles via xattrs to use dfa matching

This converts profile attachment based on xattrs to a fixed extended
conditional using dfa matching.

This has a couple of advantages
- pattern matching can be used for the xattr match

- xattrs can be optional for an attachment or marked as required

- the xattr attachment conditional will be able to be combined with
other extended conditionals when the flexible extended conditional
work lands.

The xattr fixed extended conditional is appended to the xmatch
conditional. If an xattr attachment is specified the profile xmatch
will be generated regardless of whether there is a pattern match on
the executable name.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

apparmor: cleanup: simplify code to get ns symlink name

ns_get_name() is called in only one place and can be folded in.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: cleanup create_aafs() error path

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: update domain transitions that are subsets of confinement at nnp

Domain transition so far have been largely blocked by no new privs,
unless the transition has been provably a subset of the previous
confinement. There was a couple problems with the previous
implementations,

- transitions that weren't explicitly a stack but resulted in a subset
of confinement were disallowed

- confinement subsets were only calculated from the previous
confinement instead of the confinement being enforced at the time of
no new privs, so transitions would have to get progressively
tighter.

Fix this by detecting and storing a reference to the task's
confinement at the "time" no new privs is set. This reference is then
used to determine whether a transition is a subsystem of the
confinement at the time no new privs was set.

Unfortunately the implementation is less than ideal in that we have to
detect no new privs after the fact when a task attempts a domain
transition. This is adequate for the currently but will not work in a
stacking situation where no new privs could be conceivably be set in
both the "host" and in the container.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: move context.h to cred.h

Now that file contexts have been moved into file, and task context
fns() and data have been split from the context, only the cred context
remains in context.h so rename to cred.h to better reflect what it
deals with.

Signed-off-by: John Johansen <john.johansen@canonical.com>

security: apparmor: remove duplicate includes

These duplicate includes have been found with scripts/checkincludes.pl but
they have been removed manually to avoid removing false positives.

Signed-off-by: Pravin Shedge <pravin.shedge4linux@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix display of .ns_name for containers

The .ns_name should not be virtualized by the current ns view. It
needs to report the ns base name as that is being used during startup
as part of determining apparmor policy namespace support.

BugLink: http://bugs.launchpad.net/bugs/1746463
Fixes: d9f02d9c237aa ("apparmor: fix display of ns name")
Cc: Stable <stable@vger.kernel.org>
Reported-by: Serge Hallyn <serge@hallyn.com>
Tested-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: annotate ->poll() instances

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

Rename superblock flags (MS_xyz -> SB_xyz)

This is a pure automated search-and-replace of the internal kernel
superblock flags.

The s_flags are now called SB_*, with the names and the values for the
moment mirroring the MS_* flags that they're equivalent to.

Note how the MS_xyz flags are the ones passed to the mount system call,
while the SB_xyz flags are what we then use in sb->s_flags.

The script to do this was:

# places to look in; re security/*: it generally should *not* be
# touched (that stuff parses mount(2) arguments directly), but
# there are two places where we really deal with superblock flags.
FILES="drivers/mtd drivers/staging/lustre fs ipc mm \
include/linux/fs.h include/uapi/linux/bfs_fs.h \
security/apparmor/apparmorfs.c security/apparmor/include/lib.h"
# the list of MS_... constants
SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \
DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \
POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \
I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \
ACTIVE NOUSER"

SED_PROG=
for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done

# we want files that contain at least one of MS_...,
# with fs/namespace.c and fs/pnode.c excluded.
L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c')

for f in $L; do sed -i $f $SED_PROG; done

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

apparmor: fix possible recursive lock warning in __aa_create_ns

Use mutex_lock_nested to provide lockdep the parent child lock ordering of
the tree.

This fixes the lockdep Warning
[ 305.275177] ============================================
[ 305.275178] WARNING: possible recursive locking detected
[ 305.275179] 4.14.0-rc7+ #320 Not tainted
[ 305.275180] --------------------------------------------
[ 305.275181] apparmor_parser/1339 is trying to acquire lock:
[ 305.275182] (&ns->lock){+.+.}, at: [<ffffffff970544dd>] __aa_create_ns+0x6d/0x1e0
[ 305.275187]
but task is already holding lock:
[ 305.275187] (&ns->lock){+.+.}, at: [<ffffffff97054b5d>] aa_prepare_ns+0x3d/0xd0
[ 305.275190]
other info that might help us debug this:
[ 305.275191] Possible unsafe locking scenario:

[ 305.275192] CPU0
[ 305.275193] ----
[ 305.275193] lock(&ns->lock);
[ 305.275194] lock(&ns->lock);
[ 305.275195]
*** DEADLOCK ***

[ 305.275196] May be due to missing lock nesting notation

[ 305.275198] 2 locks held by apparmor_parser/1339:
[ 305.275198] #0: (sb_writers#10){.+.+}, at: [<ffffffff96e9c6b7>] vfs_write+0x1a7/0x1d0
[ 305.275202] #1: (&ns->lock){+.+.}, at: [<ffffffff97054b5d>] aa_prepare_ns+0x3d/0xd0
[ 305.275205]
stack backtrace:
[ 305.275207] CPU: 1 PID: 1339 Comm: apparmor_parser Not tainted 4.14.0-rc7+ #320
[ 305.275208] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1ubuntu1 04/01/2014
[ 305.275209] Call Trace:
[ 305.275212] dump_stack+0x85/0xcb
[ 305.275214] __lock_acquire+0x141c/0x1460
[ 305.275216] ? __aa_create_ns+0x6d/0x1e0
[ 305.275218] ? ___slab_alloc+0x183/0x540
[ 305.275219] ? ___slab_alloc+0x183/0x540
[ 305.275221] lock_acquire+0xed/0x1e0
[ 305.275223] ? lock_acquire+0xed/0x1e0
[ 305.275224] ? __aa_create_ns+0x6d/0x1e0
[ 305.275227] __mutex_lock+0x89/0x920
[ 305.275228] ? __aa_create_ns+0x6d/0x1e0
[ 305.275230] ? trace_hardirqs_on_caller+0x11f/0x190
[ 305.275231] ? __aa_create_ns+0x6d/0x1e0
[ 305.275233] ? __lockdep_init_map+0x57/0x1d0
[ 305.275234] ? lockdep_init_map+0x9/0x10
[ 305.275236] ? __rwlock_init+0x32/0x60
[ 305.275238] mutex_lock_nested+0x1b/0x20
[ 305.275240] ? mutex_lock_nested+0x1b/0x20
[ 305.275241] __aa_create_ns+0x6d/0x1e0
[ 305.275243] aa_prepare_ns+0xc2/0xd0
[ 305.275245] aa_replace_profiles+0x168/0xf30
[ 305.275247] ? __might_fault+0x85/0x90
[ 305.275250] policy_update+0xb9/0x380
[ 305.275252] profile_load+0x7e/0x90
[ 305.275254] __vfs_write+0x28/0x150
[ 305.275256] ? rcu_read_lock_sched_held+0x72/0x80
[ 305.275257] ? rcu_sync_lockdep_assert+0x2f/0x60
[ 305.275259] ? __sb_start_write+0xdc/0x1c0
[ 305.275261] ? vfs_write+0x1a7/0x1d0
[ 305.275262] vfs_write+0xca/0x1d0
[ 305.275264] ? trace_hardirqs_on_caller+0x11f/0x190
[ 305.275266] SyS_write+0x49/0xa0
[ 305.275268] entry_SYSCALL_64_fastpath+0x23/0xc2
[ 305.275271] RIP: 0033:0x7fa6b22e8c74
[ 305.275272] RSP: 002b:00007ffeaaee6288 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 305.275273] RAX: ffffffffffffffda RBX: 00007ffeaaee62a4 RCX: 00007fa6b22e8c74
[ 305.275274] RDX: 0000000000000a51 RSI: 00005566a8198c10 RDI: 0000000000000004
[ 305.275275] RBP: 0000000000000a39 R08: 0000000000000a51 R09: 0000000000000000
[ 305.275276] R10: 0000000000000000 R11: 0000000000000246 R12: 00005566a8198c10
[ 305.275277] R13: 0000000000000004 R14: 00005566a72ecb88 R15: 00005566a72ec3a8

Fixes: 73688d1ed0b8 ("apparmor: refactor prepare_ns() and make usable from different views")
Signed-off-by: John Johansen <john.johansen@canonical.com>

Revert "apparmor: add base infastructure for socket mediation"

This reverts commit 651e28c5537abb39076d3949fb7618536f1d242e.

This caused a regression:
"The specific problem is that dnsmasq refuses to start on openSUSE Leap
42.2. The specific cause is that and attempt to open a PF_LOCAL socket
gets EACCES. This means that networking doesn't function on a system
with a 4.14-rc2 system."

Sadly, the developers involved seemed to be in denial for several weeks
about this, delaying the revert. This has not been a good release for
the security subsystem, and this area needs to change development
practices.

Reported-and-bisected-by: James Bottomley <James.Bottomley@hansenpartnership.com>
Tracked-by: Thorsten Leemhuis <regressions@leemhuis.info>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Seth Arnold <seth.arnold@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

apparmor: fix apparmorfs DAC access permissions

The DAC access permissions for several apparmorfs files are wrong.

.access - needs to be writable by all tasks to perform queries
the others in the set only provide a read fn so should be read only.

With policy namespace virtualization all apparmor needs to control
the permission and visibility checks directly which means DAC
access has to be allowed for all user, group, and other.

BugLink: http://bugs.launchpad.net/bugs/1713103
Fixes: c97204baf840b ("apparmor: rename apparmor file fns and data to indicate use")
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add base infastructure for socket mediation

Provide a basic mediation of sockets. This is not a full net mediation
but just whether a spcific family of socket can be used by an
application, along with setting up some basic infrastructure for
network mediation to follow.

the user space rule hav the basic form of
NETWORK RULE = [ QUALIFIERS ] 'network' [ DOMAIN ]
[ TYPE | PROTOCOL ]

DOMAIN = ( 'inet' | 'ax25' | 'ipx' | 'appletalk' | 'netrom' |
'bridge' | 'atmpvc' | 'x25' | 'inet6' | 'rose' |
'netbeui' | 'security' | 'key' | 'packet' | 'ash' |
'econet' | 'atmsvc' | 'sna' | 'irda' | 'pppox' |
'wanpipe' | 'bluetooth' | 'netlink' | 'unix' | 'rds' |
'llc' | 'can' | 'tipc' | 'iucv' | 'rxrpc' | 'isdn' |
'phonet' | 'ieee802154' | 'caif' | 'alg' | 'nfc' |
'vsock' | 'mpls' | 'ib' | 'kcm' ) ','

TYPE = ( 'stream' | 'dgram' | 'seqpacket' | 'rdm' | 'raw' |
'packet' )

PROTOCOL = ( 'tcp' | 'udp' | 'icmp' )

eg.
network,
network inet,

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

apparmor: add more debug asserts to apparmorfs

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

apparmor: add mount mediation

Add basic mount mediation. That allows controlling based on basic
mount parameters. It does not include special mount parameters for
apparmor, super block labeling, or any triggers for apparmor namespace
parameter modifications on pivot root.

default userspace policy rules have the form of
MOUNT RULE = ( MOUNT | REMOUNT | UMOUNT )

MOUNT = [ QUALIFIERS ] 'mount' [ MOUNT CONDITIONS ] [ SOURCE FILEGLOB ]
[ '->' MOUNTPOINT FILEGLOB ]

REMOUNT = [ QUALIFIERS ] 'remount' [ MOUNT CONDITIONS ]
MOUNTPOINT FILEGLOB

UMOUNT = [ QUALIFIERS ] 'umount' [ MOUNT CONDITIONS ] MOUNTPOINT FILEGLOB

MOUNT CONDITIONS = [ ( 'fstype' | 'vfstype' ) ( '=' | 'in' )
MOUNT FSTYPE EXPRESSION ]
[ 'options' ( '=' | 'in' ) MOUNT FLAGS EXPRESSION ]

MOUNT FSTYPE EXPRESSION = ( MOUNT FSTYPE LIST | MOUNT EXPRESSION )

MOUNT FSTYPE LIST = Comma separated list of valid filesystem and
virtual filesystem types (eg ext4, debugfs, etc)

MOUNT FLAGS EXPRESSION = ( MOUNT FLAGS LIST | MOUNT EXPRESSION )

MOUNT FLAGS LIST = Comma separated list of MOUNT FLAGS.

MOUNT FLAGS = ( 'ro' | 'rw' | 'nosuid' | 'suid' | 'nodev' | 'dev' |
'noexec' | 'exec' | 'sync' | 'async' | 'remount' |
'mand' | 'nomand' | 'dirsync' | 'noatime' | 'atime' |
'nodiratime' | 'diratime' | 'bind' | 'rbind' | 'move' |
'verbose' | 'silent' | 'loud' | 'acl' | 'noacl' |
'unbindable' | 'runbindable' | 'private' | 'rprivate' |
'slave' | 'rslave' | 'shared' | 'rshared' |
'relatime' | 'norelatime' | 'iversion' | 'noiversion' |
'strictatime' | 'nouser' | 'user' )

MOUNT EXPRESSION = ( ALPHANUMERIC | AARE ) ...

PIVOT ROOT RULE = [ QUALIFIERS ] pivot_root [ oldroot=OLD PUT FILEGLOB ]
[ NEW ROOT FILEGLOB ]

SOURCE FILEGLOB = FILEGLOB

MOUNTPOINT FILEGLOB = FILEGLOB

eg.
mount,
mount /dev/foo,
mount options=ro /dev/foo -> /mnt/,
mount options in (ro,atime) /dev/foo -> /mnt/,
mount options=ro options=atime,

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

apparmor: add the ability to mediate signals

Add signal mediation where the signal can be mediated based on the
signal, direction, or the label or the peer/target. The signal perms
are verified on a cross check to ensure policy consistency in the case
of incremental policy load/replacement.

The optimization of skipping the cross check when policy is guaranteed
to be consistent (single compile unit) remains to be done.

policy rules have the form of
SIGNAL_RULE = [ QUALIFIERS ] 'signal' [ SIGNAL ACCESS PERMISSIONS ]
[ SIGNAL SET ] [ SIGNAL PEER ]

SIGNAL ACCESS PERMISSIONS = SIGNAL ACCESS | SIGNAL ACCESS LIST

SIGNAL ACCESS LIST = '(' Comma or space separated list of SIGNAL
ACCESS ')'

SIGNAL ACCESS = ( 'r' | 'w' | 'rw' | 'read' | 'write' | 'send' |
'receive' )

SIGNAL SET = 'set' '=' '(' SIGNAL LIST ')'

SIGNAL LIST = Comma or space separated list of SIGNALS

SIGNALS = ( 'hup' | 'int' | 'quit' | 'ill' | 'trap' | 'abrt' |
'bus' | 'fpe' | 'kill' | 'usr1' | 'segv' | 'usr2' |
'pipe' | 'alrm' | 'term' | 'stkflt' | 'chld' | 'cont' |
'stop' | 'stp' | 'ttin' | 'ttou' | 'urg' | 'xcpu' |
'xfsz' | 'vtalrm' | 'prof' | 'winch' | 'io' | 'pwr' |
'sys' | 'emt' | 'exists' | 'rtmin+0' ... 'rtmin+32'
)

SIGNAL PEER = 'peer' '=' AARE

eg.
signal, # allow all signals
signal send set=(hup, kill) peer=foo,

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

apparmor: Fix an error code in aafs_create()

We accidentally forgot to set the error code on this path. It means we
return NULL instead of an error pointer. I looked through a bunch of
callers and I don't think it really causes a big issue, but the
documentation says we're supposed to return error pointers here.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: export that basic profile namespaces are supported

Allow userspace to detect that basic profile policy namespaces are
available.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add stacked domain labels interface

Update the user interface to support the stacked change_profile transition.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add domain label stacking info to apparmorfs

Now that the domain label transition is complete advertise it to
userspace.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: support v7 transition format compatible with label_parse

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: allow ptrace checks to be finer grained than just capability

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: update query interface to support label queries

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: switch from profiles to using labels on contexts

Begin the actual switch to using domain labels by storing them on
the context and converting the label to a singular profile where
possible.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: convert to profile block critical sections

There are still a few places where profile replacement fails to update
and a stale profile is used for mediation. Fix this by moving to
accessing the current label through a critical section that will
always ensure mediation is using the current label regardless of
whether the tasks cred has been updated or not.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix display of ns name

The ns name being displayed should go through an ns view lookup.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix apparmor_query data

The data being queried isn't always the current profile and a lookup
relative to the current profile should be done.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix policy load/remove semantics

The namespace being passed into the replace/remove profiles fns() is
not the view, but the namespace specified by the inode from the
file hook (if present) or the loading tasks ns, if accessing the
top level virtualized load/replace file interface.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add profile permission query ability

Allow userspace to query a profile about permissions, through the
transaction interface that is already used to allow userspace to
query about key,value data.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: speed up transactional queries

The simple_transaction interface is slow. It requires 4 syscalls
(open, write, read, close) per query and shares a single lock for each
queries.

So replace its use with a compatible in multi_transaction interface.
It allows for a faster 2 syscall pattern per query. After an initial
open, an arbitrary number of writes and reads can be issued. Each
write will reset the query with new data that can be read. Reads do
not clear the data, and can be issued multiple times, and used with
seek, until a new write is performed which will reset the data
available and the seek position.

Note: this keeps the single lock design, if needed moving to a per
file lock will have to come later.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add label data availability to the feature set

gsettings mediation needs to be able to determine if apparmor supports
label data queries. A label data query can be done to test for support
but its failure is indistinguishable from other failures, making it an
unreliable indicator.

Fix by making support of label data queries available as a flag in the
apparmorfs features dir tree.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add mkdir/rmdir interface to manage policy namespaces

When setting up namespaces for containers its easier for them to use
an fs interface to create the namespace for the containers
policy. Allow mkdir/rmdir under the policy/namespaces/ dir to be used
to create and remove namespaces.

BugLink: http://bugs.launchpad.net/bugs/1611078

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add policy revision file interface

Add a policy revision file to find the current revision of a ns's policy.
There is a revision file per ns, as well as a virtualized global revision
file in the base apparmor fs directory. The global revision file when
opened will provide the revision of the opening task namespace.

The revision file can be waited on via select/poll to detect apparmor
policy changes from the last read revision of the opened file. This
means that the revision file must be read after the select/poll other
wise update data will remain ready for reading.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: provide finer control over policy management

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: convert from securityfs to apparmorfs for policy ns files

Virtualize the apparmor policy/ directory so that the current
namespace affects what part of policy is seen. To do this convert to
using apparmorfs for policy namespace files and setup a magic symlink
in the securityfs apparmor dir to access those files.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>

apparmor: allow specifying an already created dir to create ns entries in

Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>

apparmor: rename apparmor file fns and data to indicate use

prefixes are used for fns/data that are not static to apparmorfs.c
with the prefixes being
aafs - special magic apparmorfs for policy namespace data
aa_sfs - for fns/data that go into securityfs
aa_fs - for fns/data that may be used in the either of aafs or
securityfs

Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>

apparmor: add custom apparmorfs that will be used by policy namespace files

AppArmor policy needs to be able to be resolved based on the policy
namespace a task is confined by. Add a base apparmorfs filesystem that
(like nsfs) will exist as a kern mount and be accessed via jump_link
through a securityfs file.

Setup the base apparmorfs fns and data, but don't use it yet.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>

apparmor: use macro template to simplify namespace seq_files

Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>

apparmor: use macro template to simplify profile seq_files

Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>

apparmor: move to per loaddata files, instead of replicating in profiles

The loaddata sets cover more than just a single profile and should
be tracked at the ns level. Move the load data files under the namespace
and reference the files from the profiles via a symlink.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>

apparmor: Fix error cod in __aa_fs_profile_mkdir()

We can either return PTR_ERR(NULL) or a PTR_ERR(a valid pointer) here.
Returning NULL is probably not good, but since this happens at boot
then we are probably already toasted if we were to hit this bug in real
life. In other words, it seems like a very low severity bug to me.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmorfs: Use seq_putc() in two functions

Two single characters (line breaks) should be put into a sequence.
Thus use the corresponding function "seq_putc".

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmorfs: Combine two function calls into one in aa_fs_seq_raw_abi_show()

A bit of data was put into a sequence by two separate function calls.
Print the same data by a single function call instead.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmorfs: replace CURRENT_TIME with current_time()

CURRENT_TIME macro is not y2038 safe on 32 bit systems.

The patch replaces all the uses of CURRENT_TIME by current_time().

This is also in preparation for the patch that transitions vfs
timestamps to use 64 bit time and hence make them y2038 safe.
current_time() is also planned to be transitioned to y2038 safe behavior
along with this change.

CURRENT_TIME macro will be deleted before merging the aforementioned
change.

Link: http://lkml.kernel.org/r/1491613030-11599-11-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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>

apparmor: replace remaining BUG_ON() asserts with AA_BUG()

AA_BUG() uses WARN and won't break the kernel like BUG_ON().

Signed-off-by: John Johansen <john.johansen@canonical.com>

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>

apparmor: convert change_profile to use fqname later to give better control

Moving the use of fqname to later allows learning profiles to be based
on the fqname request instead of just the hname. It also allows cleaning
up some of the name parsing and lookup by allowing the use of
the fqlookupn_profile() lib fn.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: remove unused op parameter from simple_write_to_buffer()

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: change op from int to const char *

Having ops be an integer that is an index into an op name table is
awkward and brittle. Every op change requires an edit for both the
op constant and a string in the table. Instead switch to using const
strings directly, eliminating the need for the table that needs to
be kept in sync.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add per policy ns .load, .replace, .remove interface files

Having per policy ns interface files helps with containers restoring
policy.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: pass the subject profile into profile replace/remove

This is just setup for new ns specific .load, .replace, .remove interface
files.

Signed-off-by: John Johansen <john.johansen@canonical.com>

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>

apparmor: add profile and ns params to aa_may_manage_policy()

Policy management will be expanded beyond traditional unconfined root.
This will require knowning the profile of the task doing the management
and the ns view.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: allow introspecting the policy namespace name

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: Make aa_remove_profile() callable from a different view

This is prep work for fs operations being able to remove namespaces.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add special .null file used to "close" fds at exec

Borrow the special null device file from selinux to "close" fds that
don't have sufficient permissions at exec time.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: provide userspace flag indicating binfmt_elf_mmap change

Commit 9f834ec18def ("binfmt_elf: switch to new creds when switching to new mm")
changed when the creds are installed by the binfmt_elf handler. This
affects which creds are used to mmap the executable into the address
space. Which can have an affect on apparmor policy.

Add a flag to apparmor at
/sys/kernel/security/apparmor/features/domain/fix_binfmt_elf_mmap

to make it possible to detect this semantic change so that the userspace
tools and the regression test suite can correctly deal with the change.

BugLink: http://bugs.launchpad.net/bugs/1630069
Signed-off-by: John Johansen <john.johansen@canonical.com>

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>

apparmor: refactor prepare_ns() and make usable from different views

prepare_ns() will need to be called from alternate views, and namespaces
will need to be created via different interfaces. So refactor and
allow specifying the view ns.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: constify policy name and hname

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: allow ns visibility question to consider subnses

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: rename replacedby to proxy

Proxy is shorter and a better fit than replaceby, so rename it.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: rename namespace to ns to improve code line lengths

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: split apparmor policy namespaces code into its own file

Policy namespaces will be diverging from profile management and
expanding so put it in its own file.

Signed-off-by: John Johansen <john.johansen@canonical.com>

fs: Replace CURRENT_TIME with current_time() for inode timestamps

CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_time() instead.

CURRENT_TIME is also not y2038 safe.

This is also in preparation for the patch that transitions
vfs timestamps to use 64 bit time and hence make them
y2038 safe. As part of the effort current_time() will be
extended to do range checks. Hence, it is necessary for all
file system timestamps to use current_time(). Also,
current_time() will be transitioned along with vfs to be
y2038 safe.

Note that whenever a single call to current_time() is used
to change timestamps in different inodes, it is because they
share the same time granularity.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Felipe Balbi <balbi@kernel.org>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

apparmor: use list_next_entry instead of list_entry_next

list_next_entry has been defined in list.h, so I replace list_entry_next
with it.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix ref count leak when profile sha1 hash is read

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

apparmor: fix update the mtime of the profile file on replacement

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

VFS: security/: d_inode() annotations

... except where that code acts as a filesystem driver, rather than
working with dentries given to it.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

apparmor: fix bad lock balance when introspecting policy

BugLink: http://bugs.launchpad.net/bugs/1235977

The profile introspection seq file has a locking bug when policy is viewed
from a virtual root (task in a policy namespace), introspection from the
real root is not affected.

The test for root
while (parent) {
is correct for the real root, but incorrect for tasks in a policy namespace.
This allows the task to walk backup the policy tree past its virtual root
causing it to be unlocked before the virtual root should be in the p_stop
fn.

This results in the following lockdep back trace:
[ 78.479744] [ BUG: bad unlock balance detected! ]
[ 78.479792] 3.11.0-11-generic #17 Not tainted
[ 78.479838] -------------------------------------
[ 78.479885] grep/2223 is trying to release lock (&ns->lock) at:
[ 78.479952] [<ffffffff817bf3be>] mutex_unlock+0xe/0x10
[ 78.480002] but there are no more locks to release!
[ 78.480037]
[ 78.480037] other info that might help us debug this:
[ 78.480037] 1 lock held by grep/2223:
[ 78.480037] #0: (&p->lock){+.+.+.}, at: [<ffffffff812111bd>] seq_read+0x3d/0x3d0
[ 78.480037]
[ 78.480037] stack backtrace:
[ 78.480037] CPU: 0 PID: 2223 Comm: grep Not tainted 3.11.0-11-generic #17
[ 78.480037] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 78.480037] ffffffff817bf3be ffff880007763d60 ffffffff817b97ef ffff8800189d2190
[ 78.480037] ffff880007763d88 ffffffff810e1c6e ffff88001f044730 ffff8800189d2190
[ 78.480037] ffffffff817bf3be ffff880007763e00 ffffffff810e5bd6 0000000724fe56b7
[ 78.480037] Call Trace:
[ 78.480037] [<ffffffff817bf3be>] ? mutex_unlock+0xe/0x10
[ 78.480037] [<ffffffff817b97ef>] dump_stack+0x54/0x74
[ 78.480037] [<ffffffff810e1c6e>] print_unlock_imbalance_bug+0xee/0x100
[ 78.480037] [<ffffffff817bf3be>] ? mutex_unlock+0xe/0x10
[ 78.480037] [<ffffffff810e5bd6>] lock_release_non_nested+0x226/0x300
[ 78.480037] [<ffffffff817bf2fe>] ? __mutex_unlock_slowpath+0xce/0x180
[ 78.480037] [<ffffffff817bf3be>] ? mutex_unlock+0xe/0x10
[ 78.480037] [<ffffffff810e5d5c>] lock_release+0xac/0x310
[ 78.480037] [<ffffffff817bf2b3>] __mutex_unlock_slowpath+0x83/0x180
[ 78.480037] [<ffffffff817bf3be>] mutex_unlock+0xe/0x10
[ 78.480037] [<ffffffff81376c91>] p_stop+0x51/0x90
[ 78.480037] [<ffffffff81211408>] seq_read+0x288/0x3d0
[ 78.480037] [<ffffffff811e9d9e>] vfs_read+0x9e/0x170
[ 78.480037] [<ffffffff811ea8cc>] SyS_read+0x4c/0xa0
[ 78.480037] [<ffffffff817ccc9d>] system_call_fastpath+0x1a/0x1f

Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

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>

apparmor: export set of capabilities supported by the apparmor module

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

apparmor: add the profile introspection file to interface

Add the dynamic namespace relative profiles file to the interace, to allow
introspection of loaded profiles and their modes.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>

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>

apparmor: add interface files for profiles and namespaces

Add basic interface files to access namespace and profile information.
The interface files are created when a profile is loaded and removed
when the profile or namespace is removed.

Signed-off-by: John Johansen <john.johansen@canonical.com>

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>

apparmor: add a features/policy dir to interface

Add a policy directory to features to contain features that can affect
policy compilation but do not affect mediation. Eg of such features would
be types of dfa compression supported, etc.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>

AppArmor: export known rlimit names/value mappings in securityfs

Since the parser needs to know which rlimits are known to the kernel,
export the list via a mask file in the "rlimit" subdirectory in the
securityfs "features" directory.

Signed-off-by: Kees Cook <kees@ubuntu.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

AppArmor: add "file" details to securityfs

Create the "file" directory in the securityfs for tracking features
related to files.

Signed-off-by: Kees Cook <kees@ubuntu.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

AppArmor: add initial "features" directory to securityfs

This adds the "features" subdirectory to the AppArmor securityfs
to display boolean features flags and the known capability mask.

Signed-off-by: Kees Cook <kees@ubuntu.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

AppArmor: refactor securityfs to use structures

Use a file tree structure to represent the AppArmor securityfs.

Signed-off-by: Kees Cook <kees@ubuntu.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

switch securityfs_create_file() to umode_t

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

apparmor: sparse fix: make aa_create_aafs static

Sparse fix: make aa_create_aafs static.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: John Johansen <john.johansen@canonical.com>

AppArmor: Ensure the size of the copy is < the buffer allocated to hold it

Actually I think in this case the appropriate thing to do is to BUG as there
is currently a case (remove) where the alloc_size needs to be larger than
the copy_size, and if copy_size is ever greater than alloc_size there is
a mistake in the caller code.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees.cook@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>

llseek: automatically add .llseek fop

All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.

The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.

New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.

The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.

Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.

Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.

===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}

@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}

@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}

@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}

@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}

@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}

@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};

@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};

@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};

@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};

@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};

// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};

@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};

// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};

// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};

// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};

@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};

// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////

@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};

@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};

@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};

@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>

AppArmor: userspace interfaces

The /proc/<pid>/attr/* interface is used for process introspection and
commands. While the apparmorfs interface is used for global introspection
and loading and removing policy.

The interface currently only contains the files necessary for loading
policy, and will be extended in the future to include sysfs style
single per file introspection inteface.

The old AppArmor 2.4 interface files have been removed into a compatibility
patch, that distros can use to maintain backwards compatibility.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>