Commit Graph

697 Commits

Author SHA1 Message Date
John Johansen
a2f31df06b 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>
2022-10-03 14:49:04 -07:00
John Johansen
70f24a9f90 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>
2022-10-03 14:49:04 -07:00
John Johansen
14d37a7f14 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>
2022-10-03 14:49:04 -07:00
John Johansen
73c7e91c8b apparmor: Remove unnecessary size check when unpacking trans_table
The index into the trans_table has a max size of 2^24 bits which the
code was testing but this is unnecessary as unpack_array can only
unpack a table of 2^16 bits in size so the table unpacked will never
be larger than what can be indexed, and any test here is redundant.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:04 -07:00
John Johansen
1ddece8cd0 apparmor: Fix doc comment for compute_fperms
When compute_fperms was moved to policy_compat and made static it
was renamed from aa_compute_fperms to just compute_fperms to help
indicate it is only available statically. Unfortunately the doc
comment did not also get updated to reflect the change.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:04 -07:00
Xiu Jianfeng
65f7f666f2 apparmor: make __aa_path_perm() static
Make __aa_path_perm() static as it's only used inside apparmor/file.c.

Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:04 -07:00
Gaosheng Cui
adaa9a3f72 apparmor: Simplify obtain the newest label on a cred
In aa_get_task_label(), aa_get_newest_cred_label(__task_cred(task))
can do the same things as aa_get_newest_label(__aa_task_raw_label(task)),
so we can replace it and remove __aa_task_raw_label() to simplify the code.

Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:04 -07:00
John Johansen
1f939c6bd1 apparmor: Fix regression in stacking due to label flags
The unconfined label flag is not being computed correctly. It
should only be set if all the profiles in the vector are set, which
is different than what is required for the debug and stale flag
that are set if any on the profile flags are set.

Fixes: c1ed5da197 ("apparmor: allow label to carry debug flags")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:04 -07:00
John Johansen
961f3e3de1 apparmor: fix aa_class_names[] to match reserved classes
The class name map did not have the reserved names added. Fix this

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:04 -07:00
John Johansen
1ad22fcc4d 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>
2022-10-03 14:49:04 -07:00
John Johansen
217af7e2f4 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>
2022-10-03 14:49:04 -07:00
John Johansen
3bf3d728a5 apparmor: verify loaded permission bits masks don't overlap
Add an additional verification that loaded permission sets don't
overlap in ways that are not intended. This will help ensure that
permission accumulation can't result in an invalid permission set.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:04 -07:00
John Johansen
3dfd16ab69 apparmor: cleanup: move perm accumulation into perms.h
Perm accumulation is going to be used much more frequently so let
the compiler figure out if it can be optimized when used.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:04 -07:00
John Johansen
0bece4fa97 apparmor: make sure perm indexes are accumulated
accumulate permission indexes on a first encountered basis. This
favors original rulesets so that new ones can not override without
profile replacement.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:04 -07:00
John Johansen
670f31774a apparmor: verify permission table indexes
While the dfa xindex's are verified, the indexes in the permission
table are not currently verified. Fix this.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
fd1b2b95a2 apparmor: add the ability for policy to specify a permission table
Currently permissions are encoded in the dfa accept entries that are
then mapped to an internal permission structure. This limits the
permissions that userspace can specify, so allow userspace to directly
specify the permission table.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
371e50a0b1 apparmor: make unpack_array return a trianary value
currently unpack_array() does not return an error nor whether the
array is not present. The ability to detect an error or the array
not being present is needed so rework the unpack_array() to return
the needed information.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
ad596ea74e apparmor: group dfa policydb unpacking
There are currently three policydb rule groupings (xmatch, file,
policydb) that each do their own slightly different thing. Group them
into a single routine and unify.

This extends/unifies dfa features by
- all dfas are allowed having an optional start field
- all dfas are allowed having a string/transition table

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
a0792e2ced apparmor: make transition table unpack generic so it can be reused
Currently the transition table is tied to the file dfa. Make it so
we can unpack a transition table against any dfa.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
22fac8a051 apparmor: add user mode flag
Allow the profile to contain a user mode prompt flag. This works similar
to complain mode but will try to send messages to a userspace daemon.
If the daemon is not present or timesout regular informent will occur.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
8c4b785a86 apparmor: add mediation class information to auditing
Audit messages currently don't contain the mediation class which can
make them less clear than they should be in some circumstances. With
newer mediation classes coming this potential confusion will become
worse.

Fix this by adding the mediatin class to the messages.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
90917d5b68 apparmor: extend permissions to support a label and tag string
add indexes for label and tag entries. Rename the domain table to the
str_table as its a shared string table with label and tags.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
caa9f579ca apparmor: isolate policy backwards compatibility to its own file
The details of mapping old policy into newer policy formats clutters
up the unpack code and makes it possible to accidentally use old
mappings in code, so isolate the mapping code into its own file.

This will become more important when the dfa remapping code lands,
as it will greatly expand the compat code base.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
ae6d35ed0a apparmor: extend xindex size
Allow the xindex to have 2^24 entries.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
b06a62ebf5 apparmor: move dfa perm macros into policy_unpack
Now that the permission remapping macros aren't needed anywhere except
during profile unpack, move them.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
3c076531c5 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.

Note: that this does not bring full auditing control of the
permissions as there are not enough bits. The quieting of denials is
provided as that is used more than forced auditing of allowed
permissions.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
1cf26c3d2c apparmor: fix apparmor mediating locking non-fs unix sockets
the v8 and earlier policy does not encode the locking permission for
no-fs unix sockets. However the kernel is enforcing mediation.

Add the AA_MAY_LOCK perm to v8 and earlier computed perm mask which will
grant permission for all current abi profiles, but still allow specifying
auditing of the operation if needed.

Link: http://bugs.launchpad.net/bugs/1780227
Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
1b5a6198f5 apparmor: Fix abi check to include v8 abi
The v8 abi is supported by the kernel but the userspace supported
version check does not allow for it. This was missed when v8 was added
due to a bug in the userspace compiler which was setting an older abi
version for v8 encoding (which is forward compatible except on the
network encoding). However it is possible to detect the network
encoding by checking the policydb network support which the code
does. The end result was that missing the abi flag worked until
userspace was fixed and began correctly checking for the v8 abi
version.

Fixes: 56974a6fcf ("apparmor: add base infastructure for socket mediation")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
33fc95d829 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>
2022-10-03 14:49:03 -07:00
John Johansen
e844fe9b51 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>
2022-10-03 14:49:03 -07:00
John Johansen
bf690f59d0 apparmor: cleanup shared permission struct
The shared permissions struct has the stop field which is unneeded
and the "reserved" subtree field commented which is needed. Also
reorganize so that the entries are logically grouped.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
2d63dd43ae apparmor: convert xmatch lookup to use accept as an index
Remap xmatch dfa accept table from embedded perms to an index and then
move xmatch lookup to use accept entry to index into the xmatch table.

This is step towards unifying permission lookup and reducing the
size of permissions tables.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
7572fea31e apparmor: convert fperm lookup to use accept as an index
Remap file dfa accept table from embedded perms to index and then move
fperm lookup to use the accept entry as an index into the fperm table.

This is a step toward unifying permission lookup.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:03 -07:00
John Johansen
048d495444 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>
2022-10-03 14:49:03 -07:00
John Johansen
53bdc46f4b 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>
2022-10-03 14:49:03 -07:00
John Johansen
e2967ede22 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>
2022-10-03 14:49:03 -07:00
John Johansen
e48ffd24c1 apparmor: convert xmatch to use aa_perms structure
Convert xmatch from using perms encoded in the accept entry of the
dfa to the common external aa_perms in a table.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:02 -07:00
John Johansen
0310f093ba apparmor: rework and cleanup fperm computation
shorten the name of some of the mapping functions which shortens line
lengths.

change the mapping so it returns the perm table instead of operating
directly on the file struct.

Handle potential memory allocation failure.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:02 -07:00
John Johansen
754f209b81 apparmor: move fperm computation into policy_unpack
fperm computation is only needed during policy_unpack so move the
code there to isolate it fromt the run time code.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:02 -07:00
Mike Salvatore
b5b5799350 apparmor: compute xmatch permissions on profile load
Rather than computing xmatch permissions each time access is requested,
these 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>
2022-10-03 14:49:02 -07:00
Mike Salvatore
408d53e923 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>
2022-10-03 14:49:02 -07:00
Jon Tourville
2218d08123 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>
2022-10-03 14:49:02 -07:00
Jon Tourville
f4d6b94b40 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>
2022-10-03 14:49:02 -07:00
John Johansen
f47acc4b7c apparmor: reserve mediation classes
Reserve mediation classes that exist in out of tree development
branches or are used by userspace mediation helpers.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:02 -07:00
John Johansen
9c4557efc5 apparmor: fix lockdep warning when removing a namespace
Fix the following lockdep warning

[ 1119.158984] ============================================
[ 1119.158988] WARNING: possible recursive locking detected
[ 1119.158996] 6.0.0-rc1+ #257 Tainted: G            E    N
[ 1119.158999] --------------------------------------------
[ 1119.159001] bash/80100 is trying to acquire lock:
[ 1119.159007] ffff88803e79b4a0 (&ns->lock/1){+.+.}-{4:4}, at: destroy_ns.part.0+0x43/0x140
[ 1119.159028]
               but task is already holding lock:
[ 1119.159030] ffff8881009764a0 (&ns->lock/1){+.+.}-{4:4}, at: aa_remove_profiles+0x3f0/0x640
[ 1119.159040]
               other info that might help us debug this:
[ 1119.159042]  Possible unsafe locking scenario:

[ 1119.159043]        CPU0
[ 1119.159045]        ----
[ 1119.159047]   lock(&ns->lock/1);
[ 1119.159051]   lock(&ns->lock/1);
[ 1119.159055]
                *** DEADLOCK ***

Which is caused by an incorrect lockdep nesting notation

Fixes: feb3c766a3 ("apparmor: fix possible recursive lock warning in __aa_create_ns")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:49:02 -07:00
Gaosheng Cui
c73275cf68 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: 1dea3b41e8 ("apparmor: speed up transactional queries")
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-10-03 14:48:54 -07:00
Lukas Bulwahn
79eb2711c9 apparmor: correct config reference to intended one
Commit 5bfcbd22ee ("apparmor: Enable tuning of policy paranoid load for
embedded systems") introduces the config SECURITY_APPARMOR_PARANOID_LOAD,
but then refers in the code to SECURITY_PARANOID_LOAD; note the missing
APPARMOR in the middle.

Correct this to the introduced and intended config option.

Fixes: 5bfcbd22ee ("apparmor: Enable tuning of policy paranoid load for embedded systems")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-07-20 13:22:19 -07:00
John Johansen
eac931254d 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>
2022-07-19 04:14:22 -07:00
John Johansen
f567e7fada 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>
2022-07-19 02:57:15 -07:00
John Johansen
c1ed5da197 apparmor: allow label to carry debug flags
Allow labels to have debug flags that can be used to trigger debug output
only from profiles/labels that are marked. This can help reduce debug
output by allowing debug to be target to a specific confinement condition.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2022-07-19 02:55:45 -07:00