Commit Graph

164 Commits

Author SHA1 Message Date
John Johansen
9208c05f9f apparmor: add support for 2^24 states to the dfa state machine.
Currently the dfa state machine is limited by its default, next, and
check tables using u16. Allow loading of u32 tables, and if u16 tables
are loaded map them to u32.

The number of states allowed does not increase to 2^32 because the
base table uses the top 8 bits of its u32 for flags. Moving the flags
into a separate table allowing a full 2^32 bit range wil be done in
a separate patch.

Link: https://gitlab.com/apparmor/apparmor/-/issues/419
Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-11-26 19:21:05 -08:00
Leesoo Ahn
3dd384108d apparmor: fix possible NULL pointer dereference
profile->parent->dents[AAFS_PROF_DIR] could be NULL only if its parent is made
from __create_missing_ancestors(..) and 'ent->old' is NULL in
aa_replace_profiles(..).
In that case, it must return an error code and the code, -ENOENT represents
its state that the path of its parent is not existed yet.

BUG: kernel NULL pointer dereference, address: 0000000000000030
PGD 0 P4D 0
PREEMPT SMP PTI
CPU: 4 PID: 3362 Comm: apparmor_parser Not tainted 6.8.0-24-generic #24
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
RIP: 0010:aafs_create.constprop.0+0x7f/0x130
Code: 4c 63 e0 48 83 c4 18 4c 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d 31 d2 31 c9 31 f6 31 ff 45 31 c0 45 31 c9 45 31 d2 c3 cc cc cc cc <4d> 8b 55 30 4d 8d ba a0 00 00 00 4c 89 55 c0 4c 89 ff e8 7a 6a ae
RSP: 0018:ffffc9000b2c7c98 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000000041ed RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000b2c7cd8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff82baac10
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007be9f22cf740(0000) GS:ffff88817bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000030 CR3: 0000000134b08000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 ? show_regs+0x6d/0x80
 ? __die+0x24/0x80
 ? page_fault_oops+0x99/0x1b0
 ? kernelmode_fixup_or_oops+0xb2/0x140
 ? __bad_area_nosemaphore+0x1a5/0x2c0
 ? find_vma+0x34/0x60
 ? bad_area_nosemaphore+0x16/0x30
 ? do_user_addr_fault+0x2a2/0x6b0
 ? exc_page_fault+0x83/0x1b0
 ? asm_exc_page_fault+0x27/0x30
 ? aafs_create.constprop.0+0x7f/0x130
 ? aafs_create.constprop.0+0x51/0x130
 __aafs_profile_mkdir+0x3d6/0x480
 aa_replace_profiles+0x83f/0x1270
 policy_update+0xe3/0x180
 profile_load+0xbc/0x150
 ? rw_verify_area+0x47/0x140
 vfs_write+0x100/0x480
 ? __x64_sys_openat+0x55/0xa0
 ? syscall_exit_to_user_mode+0x86/0x260
 ksys_write+0x73/0x100
 __x64_sys_write+0x19/0x30
 x64_sys_call+0x7e/0x25c0
 do_syscall_64+0x7f/0x180
 entry_SYSCALL_64_after_hwframe+0x78/0x80
RIP: 0033:0x7be9f211c574
Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d d5 ea 0e 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89
RSP: 002b:00007ffd26f2b8c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00005d504415e200 RCX: 00007be9f211c574
RDX: 0000000000001fc1 RSI: 00005d504418bc80 RDI: 0000000000000004
RBP: 0000000000001fc1 R08: 0000000000001fc1 R09: 0000000080000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005d504418bc80
R13: 0000000000000004 R14: 00007ffd26f2b9b0 R15: 00007ffd26f2ba30
 </TASK>
Modules linked in: snd_seq_dummy snd_hrtimer qrtr snd_hda_codec_generic snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec snd_hda_core snd_hwdep snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device i2c_i801 snd_timer i2c_smbus qxl snd soundcore drm_ttm_helper lpc_ich ttm joydev input_leds serio_raw mac_hid binfmt_misc msr parport_pc ppdev lp parport efi_pstore nfnetlink dmi_sysfs qemu_fw_cfg ip_tables x_tables autofs4 hid_generic usbhid hid ahci libahci psmouse virtio_rng xhci_pci xhci_pci_renesas
CR2: 0000000000000030
---[ end trace 0000000000000000 ]---
RIP: 0010:aafs_create.constprop.0+0x7f/0x130
Code: 4c 63 e0 48 83 c4 18 4c 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d 31 d2 31 c9 31 f6 31 ff 45 31 c0 45 31 c9 45 31 d2 c3 cc cc cc cc <4d> 8b 55 30 4d 8d ba a0 00 00 00 4c 89 55 c0 4c 89 ff e8 7a 6a ae
RSP: 0018:ffffc9000b2c7c98 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000000041ed RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000b2c7cd8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff82baac10
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007be9f22cf740(0000) GS:ffff88817bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000030 CR3: 0000000134b08000 CR4: 00000000000006f0

Signed-off-by: Leesoo Ahn <lsahn@ooseel.net>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-05-10 08:59:05 -07:00
Linus Torvalds
237c31cb5d + Features
- switch policy hash fro sha1 to sha256
 
 + Bug Fixes
   - Fix refcount leak in task_kill
   - Fix leak of pdb objects and trans_table
   - avoid crash when parse profie name is empty
 
 + Cleanups
   - add static to stack_msg and nulldfa
   - more kernel-doc cleanups
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Merge tag 'apparmor-pr-2024-01-18' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

Pull AppArmor updates from John Johansen:
 "This adds a single feature, switch the hash used to check policy from
  sha1 to sha256

  There are fixes for two memory leaks, and refcount bug and a potential
  crash when a profile name is empty. Along with a couple minor code
  cleanups.

  Summary:

  Features
   - switch policy hash from sha1 to sha256

  Bug Fixes
   - Fix refcount leak in task_kill
   - Fix leak of pdb objects and trans_table
   - avoid crash when parse profie name is empty

  Cleanups
   - add static to stack_msg and nulldfa
   - more kernel-doc cleanups"

* tag 'apparmor-pr-2024-01-18' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
  apparmor: Fix memory leak in unpack_profile()
  apparmor: avoid crash when parsed profile name is empty
  apparmor: fix possible memory leak in unpack_trans_table
  apparmor: free the allocated pdb objects
  apparmor: Fix ref count leak in task_kill
  apparmor: cleanup network hook comments
  apparmor: add missing params to aa_may_ptrace kernel-doc comments
  apparmor: declare nulldfa as static
  apparmor: declare stack_msg as static
  apparmor: switch SECURITY_APPARMOR_HASH from sha1 to sha256
2024-01-19 10:53:55 -08:00
Linus Torvalds
488926926a misc cleanups (the part that hadn't been picked by individual fs trees)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull misc filesystem updates from Al Viro:
 "Misc cleanups (the part that hadn't been picked by individual fs
  trees)"

* tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  apparmorfs: don't duplicate kfree_link()
  orangefs: saner arguments passing in readdir guts
  ocfs2_find_match(): there's no such thing as NULL or negative ->d_parent
  reiserfs_add_entry(): get rid of pointless namelen checks
  __ocfs2_add_entry(), ocfs2_prepare_dir_for_insert(): namelen checks
  ext4_add_entry(): ->d_name.len is never 0
  befs: d_obtain_alias(ERR_PTR(...)) will do the right thing
  affs: d_obtain_alias(ERR_PTR(...)) will do the right thing
  /proc/sys: use d_splice_alias() calling conventions to simplify failure exits
  hostfs: use d_splice_alias() calling conventions to simplify failure exits
  udf_fiiter_add_entry(): check for zero ->d_name.len is bogus...
  udf: d_obtain_alias(ERR_PTR(...)) will do the right thing...
  udf: d_splice_alias() will do the right thing on ERR_PTR() inode
  nfsd: kill stale comment about simple_fill_super() requirements
  bfs_add_entry(): get rid of pointless ->d_name.len checks
  nilfs2: d_obtain_alias(ERR_PTR(...)) will do the right thing...
  zonefs: d_splice_alias() will do the right thing on ERR_PTR() inode
2024-01-11 20:23:50 -08:00
John Johansen
8026e40608 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: 157a3537d6 ("apparmor: Fix regression in mount mediation")
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2024-01-03 12:10:29 -08:00
Al Viro
c5f3fd2178 apparmorfs: don't duplicate kfree_link()
rawdata_link_cb() is identical to it

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2023-12-21 12:53:43 -05:00
Dimitri John Ledkov
e44a4dc4b3 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>
2023-11-19 00:47:56 -08:00
Linus Torvalds
6bdfe2d88b + Features
- optimize retrieving current task secid
   - add base io_uring mediation
   - add base userns mediation
   - improve buffer allocation
   - allow restricting unprivilege change_profile
 
 + Cleanups
   - Fix kernel doc comments
   - remove unused declarations
   - remove unused functions
   - remove unneeded #ifdef
   - remove unused macros
   - mark fns static
   - cleanup fn with unused return values
   - cleanup audit data
   - pass cred through to audit data
   - refcount the pdb instead of using duplicates
   - make SK_CTX macro an inline fn
   - some comment cleanups
 
 + Bug fixes
   - fix regression in mount mediation
   - fix invalid refenece
   - use passed in gfp flags
   - advertise avaiability of extended perms and disconnected.path
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Merge tag 'apparmor-pr-2023-11-03' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

Pull apparmor updates from John Johansen:
 "This adds initial support for mediating io_uring and userns creation.
  Adds a new restriction that tightens the use of change_profile, and a
  couple of optimizations to reduce performance bottle necks that have
  been found when retrieving the current task's secid and allocating
  work buffers.

  The majority of the patch set continues cleaning up and simplifying
  the code (fixing comments, removing now dead functions, and macros
  etc). Finally there are 4 bug fixes, with the regression fix having
  had a couple months of testing.

  Features:
   - optimize retrieving current task secid
   - add base io_uring mediation
   - add base userns mediation
   - improve buffer allocation
   - allow restricting unprivilege change_profile

  Cleanups:
   - Fix kernel doc comments
   - remove unused declarations
   - remove unused functions
   - remove unneeded #ifdef
   - remove unused macros
   - mark fns static
   - cleanup fn with unused return values
   - cleanup audit data
   - pass cred through to audit data
   - refcount the pdb instead of using duplicates
   - make SK_CTX macro an inline fn
   - some comment cleanups

  Bug fixes:
   - fix regression in mount mediation
   - fix invalid refenece
   - use passed in gfp flags
   - advertise avaiability of extended perms and disconnected.path"

* tag 'apparmor-pr-2023-11-03' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor: (39 commits)
  apparmor: Fix some kernel-doc comments
  apparmor: Fix one kernel-doc comment
  apparmor: Fix some kernel-doc comments
  apparmor: mark new functions static
  apparmor: Fix regression in mount mediation
  apparmor: cache buffers on percpu list if there is lock contention
  apparmor: add io_uring mediation
  apparmor: add user namespace creation mediation
  apparmor: allow restricting unprivileged change_profile
  apparmor: advertise disconnected.path is available
  apparmor: refcount the pdb
  apparmor: provide separate audit messages for file and policy checks
  apparmor: pass cred through to audit info.
  apparmor: rename audit_data->label to audit_data->subj_label
  apparmor: combine common_audit_data and apparmor_audit_data
  apparmor: rename SK_CTX() to aa_sock and make it an inline fn
  apparmor: Optimize retrieving current task secid
  apparmor: remove unused functions in policy_ns.c/.h
  apparmor: remove unneeded #ifdef in decompress_zstd()
  apparmor: fix invalid reference on profile->disconnected
  ...
2023-11-03 09:48:17 -10:00
Georgia Garcia
c4371d9063 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>
2023-10-18 15:58:49 -07:00
John Johansen
fa9b63adab 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>
2023-10-18 15:49:02 -07:00
John Johansen
2d9da9b188 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>
2023-10-18 15:48:44 -07:00
John Johansen
e105d8079f 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>
2023-10-18 15:30:51 -07:00
John Johansen
98b824ff89 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>
2023-10-18 15:30:47 -07:00
John Johansen
90c436a64a 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>
2023-10-18 15:30:38 -07:00
Jeff Layton
7563c93494
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>
2023-10-18 14:08:30 +02:00
Xiu Jianfeng
5ebb39eb90 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>
2023-10-15 21:44:31 -07:00
Jeff Layton
6ac5422617 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>
2023-07-24 10:30:08 +02:00
Jeff Layton
46fc6b35a6 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>
2023-07-10 10:04:52 +02:00
John Johansen
180cf25799 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>
2023-07-09 17:31:11 -07:00
Christian Brauner
c54bd91e9e
fs: port ->mkdir() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("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>
2023-01-19 09:24:26 +01:00
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
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
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
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
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
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
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
Xiu Jianfeng
417ea9fe97 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: a6a52579e5 ("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>
2022-07-09 15:13:59 -07:00
John Johansen
f9da5b1452 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>
2022-07-09 15:13:59 -07:00
Yang Li
564423bf9c 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>
2022-07-09 15:13:59 -07:00
John Johansen
482e8050aa 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>
2022-07-09 15:13:59 -07:00
John Johansen
d61c57fde8 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>
2022-07-09 15:13:59 -07:00
Linus Torvalds
5593a733f9 + Features
- use per file locks for transactional queries
   - update policy management capability checks to work with LSM stacking
 
 + Bug Fixes
   - check/put label on apparmor_sk_clone_security()
   - fix error check on update of label hname
   - fix introspection of of task mode for unconfined tasks
 
 + Cleanups
   - avoid -Wempty-body warning
   - remove duplicated 'Returns:' comments
   - fix doc warning
   - remove unneeded one-line hook wrappers
   - Use struct_size() helper in kzalloc()
   - fix zero-length compiler warning in AA_BUG()
   - file.h: delete duplicated word
   - delete repeated words in comments
   - Remove the repeated declaration
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Merge tag 'apparmor-pr-2021-11-10' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

Pull apparmor updates from John Johansen:
 "Features
   - use per file locks for transactional queries
   - update policy management capability checks to work with LSM stacking

  Bug Fixes:
   - check/put label on apparmor_sk_clone_security()
   - fix error check on update of label hname
   - fix introspection of of task mode for unconfined tasks

  Cleanups:
   - avoid -Wempty-body warning
   - remove duplicated 'Returns:' comments
   - fix doc warning
   - remove unneeded one-line hook wrappers
   - use struct_size() helper in kzalloc()
   - fix zero-length compiler warning in AA_BUG()
   - file.h: delete duplicated word
   - delete repeated words in comments
   - remove repeated declaration"

* tag 'apparmor-pr-2021-11-10' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
  apparmor: remove duplicated 'Returns:' comments
  apparmor: remove unneeded one-line hook wrappers
  apparmor: Use struct_size() helper in kzalloc()
  apparmor: fix zero-length compiler warning in AA_BUG()
  apparmor: use per file locks for transactional queries
  apparmor: fix doc warning
  apparmor: Remove the repeated declaration
  apparmor: avoid -Wempty-body warning
  apparmor: Fix internal policy capable check for policy management
  apparmor: fix error check
  security: apparmor: delete repeated words in comments
  security: apparmor: file.h: delete duplicated word
  apparmor: switch to apparmor to internal capable check for policy management
  apparmor: update policy capable checks to use a label
  apparmor: fix introspection of of task mode for unconfined tasks
  apparmor: check/put label on apparmor_sk_clone_security()
2021-11-11 14:47:32 -08:00
Hamza Mahfooz
d0d845a790 apparmor: use per file locks for transactional queries
As made mention of in commit 1dea3b41e8 ("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>
2021-11-03 00:46:28 -07:00
ChenXiaoSong
aa4ceed7c3 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>
2021-11-03 00:46:28 -07:00
John Johansen
92de220a7f 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>
2021-02-07 04:13:54 -08:00
Christian Brauner
549c729771
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>
2021-01-24 14:27:20 +01:00
Andy Shevchenko
9801ca279a 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: e130816164 ("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>
2020-12-15 22:46:19 -08:00
Linus Torvalds
a2b447066c Tag summary
+ Features
   - Replace zero-length array with flexible-array
   - add a valid state flags check
   - add consistency check between state and dfa diff encode flags
   - add apparmor subdir to proc attr interface
   - fail unpack if profile mode is unknown
   - add outofband transition and use it in xattr match
   - ensure that dfa state tables have entries
 
 + Cleanups
   - Use true and false for bool variable
   - Remove semicolon
   - Clean code by removing redundant instructions
   - Replace two seq_printf() calls by seq_puts() in aa_label_seq_xprint()
   - remove duplicate check of xattrs on profile attachment
   - remove useless aafs_create_symlink
 
 + Bug fixes
   - Fix memory leak of profile proxy
   - fix introspection of of task mode for unconfined tasks
   - fix nnp subset test for unconfined
   - check/put label on apparmor_sk_clone_security()
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Merge tag 'apparmor-pr-2020-06-07' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

Pull apparmor updates from John Johansen:
 "Features:
   - Replace zero-length array with flexible-array
   - add a valid state flags check
   - add consistency check between state and dfa diff encode flags
   - add apparmor subdir to proc attr interface
   - fail unpack if profile mode is unknown
   - add outofband transition and use it in xattr match
   - ensure that dfa state tables have entries

  Cleanups:
   - Use true and false for bool variable
   - Remove semicolon
   - Clean code by removing redundant instructions
   - Replace two seq_printf() calls by seq_puts() in aa_label_seq_xprint()
   - remove duplicate check of xattrs on profile attachment
   - remove useless aafs_create_symlink

  Bug fixes:
   - Fix memory leak of profile proxy
   - fix introspection of of task mode for unconfined tasks
   - fix nnp subset test for unconfined
   - check/put label on apparmor_sk_clone_security()"

* tag 'apparmor-pr-2020-06-07' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
  apparmor: Fix memory leak of profile proxy
  apparmor: fix introspection of of task mode for unconfined tasks
  apparmor: check/put label on apparmor_sk_clone_security()
  apparmor: Use true and false for bool variable
  security/apparmor/label.c: Clean code by removing redundant instructions
  apparmor: Replace zero-length array with flexible-array
  apparmor: ensure that dfa state tables have entries
  apparmor: remove duplicate check of xattrs on profile attachment.
  apparmor: add outofband transition and use it in xattr match
  apparmor: fail unpack if profile mode is unknown
  apparmor: fix nnp subset test for unconfined
  apparmor: remove useless aafs_create_symlink
  apparmor: add proc subdir to attrs
  apparmor: add consistency check between state and dfa diff encode flags
  apparmor: add a valid state flags check
  AppArmor: Remove semicolon
  apparmor: Replace two seq_printf() calls by seq_puts() in aa_label_seq_xprint()
2020-06-07 16:04:49 -07:00
Xiyu Yang
c6b39f0707 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: 5ac8c355ae ("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>
2020-05-21 15:25:51 -07:00
Gustavo A. R. Silva
fe9fd23e3b 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 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2020-05-15 13:04:55 -07:00