Commit Graph

309 Commits

Author SHA1 Message Date
Tetsuo Handa f702e11076 tomoyo: use hwight16() in tomoyo_domain_quota_is_ok()
hwight16() is much faster. While we are at it, no need to include
"perm =" part into data_race() macro, for perm is a local variable
that cannot be accessed by other threads.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2021-12-15 20:13:55 +09:00
Dmitry Vyukov 04e57a2d95 tomoyo: Check exceeded quota early in tomoyo_domain_quota_is_ok().
If tomoyo is used in a testing/fuzzing environment in learning mode,
for lots of domains the quota will be exceeded and stay exceeded
for prolonged periods of time. In such cases it's pointless (and slow)
to walk the whole acl list again and again just to rediscover that
the quota is exceeded. We already have the TOMOYO_DIF_QUOTA_WARNED flag
that notes the overflow condition. Check it early to avoid the slowdown.

[penguin-kernel]
This patch causes a user visible change that the learning mode will not be
automatically resumed after the quota is increased. To resume the learning
mode, administrator will need to explicitly clear TOMOYO_DIF_QUOTA_WARNED
flag after increasing the quota. But I think that this change is generally
preferable, for administrator likely wants to optimize the acl list for
that domain before increasing the quota, or that domain likely hits the
quota again. Therefore, don't try to care to clear TOMOYO_DIF_QUOTA_WARNED
flag automatically when the quota for that domain changed.

Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2021-12-15 20:11:07 +09:00
Luigi Rizzo 5b78ed24e8 mm/pagemap: add mmap_assert_locked() annotations to find_vma*()
find_vma() and variants need protection when used.  This patch adds
mmap_assert_lock() calls in the functions.

To make sure the invariant is satisfied, we also need to add a
mmap_read_lock() around the get_user_pages_remote() call in
get_arg_page().  The lock is not strictly necessary because the mm has
been newly created, but the extra cost is limited because the same mutex
was also acquired shortly before in __bprm_mm_init(), so it is hot and
uncontended.

[penguin-kernel@i-love.sakura.ne.jp: TOMOYO needs the same protection which get_arg_page() needs]
  Link: https://lkml.kernel.org/r/58bb6bf7-a57e-8a40-e74b-39584b415152@i-love.sakura.ne.jp

Link: https://lkml.kernel.org/r/20210731175341.3458608-1-lrizzo@google.com
Signed-off-by: Luigi Rizzo <lrizzo@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
ChenXiaoSong 98eaa63e96 tomoyo: fix doc warnings
Fix gcc W=1 warnings:

security/tomoyo/audit.c:331: warning: Function parameter or member 'matched_acl' not described in 'tomoyo_get_audit'
security/tomoyo/securityfs_if.c:146: warning: Function parameter or member 'inode' not described in 'tomoyo_release'
security/tomoyo/tomoyo.c:122: warning: Function parameter or member 'path' not described in 'tomoyo_inode_getattr'
security/tomoyo/tomoyo.c:497: warning: Function parameter or member 'clone_flags' not described in 'tomoyo_task_alloc'
security/tomoyo/util.c:92: warning: Function parameter or member 'time64' not described in 'tomoyo_convert_time'

Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
[ penguin-kernel: Also adjust spaces and similar warnings ]
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2021-06-16 00:01:28 +09:00
Jens Axboe 4e53d1701b tomoyo: don't special case PF_IO_WORKER for PF_KTHREAD
Since commit 3bfe610669 ("io-wq: fork worker threads from original
task") stopped using PF_KTHREAD flag for the io_uring PF_IO_WORKER threads,
tomoyo_kernel_service() no longer needs to check PF_IO_WORKER flag.

(This is a 5.12+ patch. Please don't send to stable kernels.)

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2021-03-28 13:11:29 +09:00
Tetsuo Handa 9c83465f32 tomoyo: recognize kernel threads correctly
Commit db68ce10c4 ("new helper: uaccess_kernel()") replaced
segment_eq(get_fs(), KERNEL_DS) with uaccess_kernel(). But the correct
method for tomoyo to check whether current is a kernel thread in order
to assume that kernel threads are privileged for socket operations was
(current->flags & PF_KTHREAD). Now that uaccess_kernel() became 0 on x86,
tomoyo has to fix this problem. Do like commit 942cb357ae ("Smack:
Handle io_uring kernel thread privileges") does.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2021-02-01 11:53:05 +09:00
Tetsuo Handa 5797e861e4 tomoyo: ignore data race while checking quota
syzbot is reporting that tomoyo's quota check is racy [1]. But this check
is tolerant of some degree of inaccuracy. Thus, teach KCSAN to ignore
this data race.

[1] https://syzkaller.appspot.com/bug?id=999533deec7ba6337f8aa25d8bd1a4d5f7e50476

Reported-by: syzbot <syzbot+0789a72b46fd91431bd8@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2021-02-01 11:52:11 +09:00
Tetsuo Handa 15269fb193 tomoyo: Fix typo in comments.
Spotted by developers and codespell program.

Co-developed-by: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Co-developed-by: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2020-12-06 13:44:57 +09:00
Zheng Zengkai 1b6b924efe tomoyo: Fix null pointer check
Since tomoyo_memory_ok() will check for null pointer returned by
kzalloc() in tomoyo_assign_profile(), tomoyo_assign_namespace(),
tomoyo_get_name() and tomoyo_commit_ok(), then emit OOM warnings
if needed. And this is the expected behavior as informed by
Tetsuo Handa.

Let's add __GFP_NOWARN to kzalloc() in those related functions.
Besides, to achieve this goal, remove the null check for entry
right after kzalloc() in tomoyo_assign_namespace().

Reported-by: Hulk Robot <hulkci@huawei.com>
Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2020-11-27 19:36:11 +09:00
Tetsuo Handa e991a40b3d tomoyo: Limit wildcard recursion depth.
Since wildcards that need recursion consume kernel stack memory (or might
cause CPU stall warning problem), we cannot allow infinite recursion.

Since TOMOYO 1.8 survived with 20 recursions limit for 5 years, nobody
would complain if applying this limit to TOMOYO 2.6.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2020-11-03 13:50:02 +09:00
Arnd Bergmann d9594e0409 tomoyo: fix clang pointer arithmetic warning
clang warns about additions on NULL pointers being undefined in C:

security/tomoyo/securityfs_if.c:226:59: warning: arithmetic on a null pointer treated as a cast from integer to pointer is a GNU extension [-Wnull-pointer-arithmetic]
        securityfs_create_file(name, mode, parent, ((u8 *) NULL) + key,

Change the code to instead use a cast through uintptr_t to avoid
the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2020-10-28 23:21:43 +09:00
Tetsuo Handa a207516776 tomoyo: Loosen pathname/domainname validation.
Since commit e2dc9bf3f5 ("umd: Transform fork_usermode_blob into
fork_usermode_driver") started calling execve() on a program written in
a local mount which is not connected to mount tree,
tomoyo_realpath_from_path() started returning a pathname in
"$fsname:/$pathname" format which violates TOMOYO's domainname rule that
it must start with "<$namespace>" followed by zero or more repetitions of
pathnames which start with '/'.

Since $fsname must not contain '.' since commit 79c0b2df79 ("add
filesystem subtype support"), tomoyo_correct_path() can recognize a token
which appears '/' before '.' appears (e.g. proc:/self/exe ) as a pathname
while rejecting a token which appears '.' before '/' appears (e.g.
exec.realpath="/bin/bash" ) as a condition parameter.

Therefore, accept domainnames which contain pathnames which do not start
with '/' but contain '/' before '.' (e.g. <kernel> tmpfs:/bpfilter_umh ).

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2020-10-12 19:53:34 +09:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Peter Xu 64019a2e46 mm/gup: remove task_struct pointer for all gup code
After the cleanup of page fault accounting, gup does not need to pass
task_struct around any more.  Remove that parameter in the whole gup
stack.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Link: http://lkml.kernel.org/r/20200707225021.200906-26-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:04 -07:00
Eric W. Biederman be619f7f06 exec: Implement kernel_execve
To allow the kernel not to play games with set_fs to call exec
implement kernel_execve.  The function kernel_execve takes pointers
into kernel memory and copies the values pointed to onto the new
userspace stack.

The calls with arguments from kernel space of do_execve are replaced
with calls to kernel_execve.

The calls do_execve and do_execveat are made static as there are now
no callers outside of exec.

The comments that mention do_execve are updated to refer to
kernel_execve or execve depending on the circumstances.  In addition
to correcting the comments, this makes it easy to grep for do_execve
and verify it is not used.

Inspired-by: https://lkml.kernel.org/r/20200627072704.2447163-1-hch@lst.de
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/87wo365ikj.fsf@x220.int.ebiederm.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2020-07-21 08:24:52 -05:00
Masahiro Yamada a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
Linus Torvalds 15a2bc4dbb Merge branch 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull execve updates from Eric Biederman:
 "Last cycle for the Nth time I ran into bugs and quality of
  implementation issues related to exec that could not be easily be
  fixed because of the way exec is implemented. So I have been digging
  into exec and cleanup up what I can.

  I don't think I have exec sorted out enough to fix the issues I
  started with but I have made some headway this cycle with 4 sets of
  changes.

   - promised cleanups after introducing exec_update_mutex

   - trivial cleanups for exec

   - control flow simplifications

   - remove the recomputation of bprm->cred

  The net result is code that is a bit easier to understand and work
  with and a decrease in the number of lines of code (if you don't count
  the added tests)"

* 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (24 commits)
  exec: Compute file based creds only once
  exec: Add a per bprm->file version of per_clear
  binfmt_elf_fdpic: fix execfd build regression
  selftests/exec: Add binfmt_script regression test
  exec: Remove recursion from search_binary_handler
  exec: Generic execfd support
  exec/binfmt_script: Don't modify bprm->buf and then return -ENOEXEC
  exec: Move the call of prepare_binprm into search_binary_handler
  exec: Allow load_misc_binary to call prepare_binprm unconditionally
  exec: Convert security_bprm_set_creds into security_bprm_repopulate_creds
  exec: Factor security_bprm_creds_for_exec out of security_bprm_set_creds
  exec: Teach prepare_exec_creds how exec treats uids & gids
  exec: Set the point of no return sooner
  exec: Move handling of the point of no return to the top level
  exec: Run sync_mm_rss before taking exec_update_mutex
  exec: Fix spelling of search_binary_handler in a comment
  exec: Move the comment from above de_thread to above unshare_sighand
  exec: Rename flush_old_exec begin_new_exec
  exec: Move most of setup_new_exec into flush_old_exec
  exec: In setup_new_exec cache current in the local variable me
  ...
2020-06-04 14:07:08 -07:00
Linus Torvalds 9ff7258575 Merge branch 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull proc updates from Eric Biederman:
 "This has four sets of changes:

   - modernize proc to support multiple private instances

   - ensure we see the exit of each process tid exactly

   - remove has_group_leader_pid

   - use pids not tasks in posix-cpu-timers lookup

  Alexey updated proc so each mount of proc uses a new superblock. This
  allows people to actually use mount options with proc with no fear of
  messing up another mount of proc. Given the kernel's internal mounts
  of proc for things like uml this was a real problem, and resulted in
  Android's hidepid mount options being ignored and introducing security
  issues.

  The rest of the changes are small cleanups and fixes that came out of
  my work to allow this change to proc. In essence it is swapping the
  pids in de_thread during exec which removes a special case the code
  had to handle. Then updating the code to stop handling that special
  case"

* 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  proc: proc_pid_ns takes super_block as an argument
  remove the no longer needed pid_alive() check in __task_pid_nr_ns()
  posix-cpu-timers: Replace __get_task_for_clock with pid_for_clock
  posix-cpu-timers: Replace cpu_timer_pid_type with clock_pid_type
  posix-cpu-timers: Extend rcu_read_lock removing task_struct references
  signal: Remove has_group_leader_pid
  exec: Remove BUG_ON(has_group_leader_pid)
  posix-cpu-timer:  Unify the now redundant code in lookup_task
  posix-cpu-timer: Tidy up group_leader logic in lookup_task
  proc: Ensure we see the exit of each process tid exactly once
  rculist: Add hlists_swap_heads_rcu
  proc: Use PIDTYPE_TGID in next_tgid
  Use proc_pid_ns() to get pid_namespace from the proc superblock
  proc: use named enums for better readability
  proc: use human-readable values for hidepid
  docs: proc: add documentation for "hidepid=4" and "subset=pid" options and new mount behavior
  proc: add option to mount only a pids subset
  proc: instantiate only pids that we can ptrace on 'hidepid=4' mount option
  proc: allow to mount many instances of proc in one pid namespace
  proc: rename struct proc_fs_info to proc_fs_opts
2020-06-04 13:54:34 -07:00
Linus Torvalds 91681e8480 One patch for suppressing coccicheck's warning.
tomoyo: use true for bool variable
 
  security/tomoyo/common.c |    2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)
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Merge tag 'tomoyo-pr-20200601' of git://git.osdn.net/gitroot/tomoyo/tomoyo-test1

Pull tomoyo update from Tetsuo Handa:
 "One patch for suppressing coccicheck's warning"

* tag 'tomoyo-pr-20200601' of git://git.osdn.net/gitroot/tomoyo/tomoyo-test1:
  tomoyo: use true for bool variable
2020-06-02 17:12:07 -07:00
Al Viro 00fca6b53a tomoyo_write_control(): get rid of pointless access_ok()
address is passed only to get_user()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-29 11:02:29 -04:00
Eric W. Biederman b8bff59926 exec: Factor security_bprm_creds_for_exec out of security_bprm_set_creds
Today security_bprm_set_creds has several implementations:
apparmor_bprm_set_creds, cap_bprm_set_creds, selinux_bprm_set_creds,
smack_bprm_set_creds, and tomoyo_bprm_set_creds.

Except for cap_bprm_set_creds they all test bprm->called_set_creds and
return immediately if it is true.  The function cap_bprm_set_creds
ignores bprm->calld_sed_creds entirely.

Create a new LSM hook security_bprm_creds_for_exec that is called just
before prepare_binprm in __do_execve_file, resulting in a LSM hook
that is called exactly once for the entire of exec.  Modify the bits
of security_bprm_set_creds that only want to be called once per exec
into security_bprm_creds_for_exec, leaving only cap_bprm_set_creds
behind.

Remove bprm->called_set_creds all of it's former users have been moved
to security_bprm_creds_for_exec.

Add or upate comments a appropriate to bring them up to date and
to reflect this change.

Link: https://lkml.kernel.org/r/87v9kszrzh.fsf_-_@x220.int.ebiederm.org
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Casey Schaufler <casey@schaufler-ca.com> # For the LSM and Smack bits
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2020-05-20 14:45:31 -05:00
Alexey Gladkov 9d78edeaec proc: proc_pid_ns takes super_block as an argument
syzbot found that

  touch /proc/testfile

causes NULL pointer dereference at tomoyo_get_local_path()
because inode of the dentry is NULL.

Before c59f415a7c, Tomoyo received pid_ns from proc's s_fs_info
directly. Since proc_pid_ns() can only work with inode, using it in
the tomoyo_get_local_path() was wrong.

To avoid creating more functions for getting proc_ns, change the
argument type of the proc_pid_ns() function. Then, Tomoyo can use
the existing super_block to get pid_ns.

Link: https://lkml.kernel.org/r/0000000000002f0c7505a5b0e04c@google.com
Link: https://lkml.kernel.org/r/20200518180738.2939611-1-gladkov.alexey@gmail.com
Reported-by: syzbot+c1af344512918c61362c@syzkaller.appspotmail.com
Fixes: c59f415a7c ("Use proc_pid_ns() to get pid_namespace from the proc superblock")
Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-05-19 07:07:50 -05:00
Zou Wei 27acbf41be tomoyo: use true for bool variable
Fixes coccicheck warning:

security/tomoyo/common.c:1028:2-13: WARNING: Assignment of 0/1 to bool variable

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2020-05-12 08:39:53 +09:00
Alexey Gladkov c59f415a7c Use proc_pid_ns() to get pid_namespace from the proc superblock
To get pid_namespace from the procfs superblock should be used a special
helper. This will avoid errors when s_fs_info will change the type.

Link: https://lore.kernel.org/lkml/20200423200316.164518-3-gladkov.alexey@gmail.com/
Link: https://lore.kernel.org/lkml/20200423112858.95820-1-gladkov.alexey@gmail.com/
Link: https://lore.kernel.org/lkml/06B50A1C-406F-4057-BFA8-3A7729EA7469@lca.pw/
Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-04-24 16:38:30 -05:00
Masahiro Yamada d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Tetsuo Handa a8772fad01 tomoyo: Use atomic_t for statistics counter
syzbot is reporting that there is a race at tomoyo_stat_update() [1].
Although it is acceptable to fail to track exact number of times policy
was updated, convert to atomic_t because this is not a hot path.

[1] https://syzkaller.appspot.com/bug?id=a4d7b973972eeed410596e6604580e0133b0fc04

Reported-by: syzbot <syzbot+efea72d4a0a1d03596cd@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2020-01-02 12:53:49 +09:00
Tetsuo Handa 6bd5ce6089 tomoyo: Suppress RCU warning at list_for_each_entry_rcu().
John Garry has reported that allmodconfig kernel on arm64 causes flood of
"RCU-list traversed in non-reader section!!" warning. I don't know what
change caused this warning, but this warning is safe because TOMOYO uses
SRCU lock instead. Let's suppress this warning by explicitly telling that
the caller is holding SRCU lock.

Reported-and-tested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2019-12-16 23:02:27 +09:00
Tetsuo Handa 6f7c41374b tomoyo: Don't use nifty names on sockets.
syzbot is reporting that use of SOCKET_I()->sk from open() can result in
use after free problem [1], for socket's inode is still reachable via
/proc/pid/fd/n despite destruction of SOCKET_I()->sk already completed.

At first I thought that this race condition applies to only open/getattr
permission checks. But James Morris has pointed out that there are more
permission checks where this race condition applies to. Thus, get rid of
tomoyo_get_socket_name() instead of conditionally bypassing permission
checks on sockets. As a side effect of this patch,
"socket:[family=\$:type=\$:protocol=\$]" in the policy files has to be
rewritten to "socket:[\$]".

[1] https://syzkaller.appspot.com/bug?id=73d590010454403d55164cca23bd0565b1eb3b74

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+0341f6a4d729d4e0acf1@syzkaller.appspotmail.com>
Reported-by: James Morris <jmorris@namei.org>
2019-12-11 19:54:10 +09:00
Thomas Gleixner ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Tetsuo Handa 4ad98ac464 tomoyo: Don't emit WARNING: string while fuzzing testing.
Commit cff0e6c3ec3e6230 ("tomoyo: Add a kernel config option for fuzzing
testing.") enabled the learning mode, but syzkaller is detecting any
"WARNING:" string as a crash. Thus, disable TOMOYO's quota warning if
built for fuzzing testing.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: James Morris <jamorris@linux.microsoft.com>
2019-05-10 14:58:35 -07:00
Tetsuo Handa 27df4b4a1b tomoyo: Change pathname calculation for read-only filesystems.
Commit 5625f2e326 ("TOMOYO: Change pathname for non-rename()able
filesystems.") intended to be applied to filesystems where the content is
not controllable from the userspace (e.g. proc, sysfs, securityfs), based
on an assumption that such filesystems do not support rename() operation.

But it turned out that read-only filesystems also do not support rename()
operation despite the content is controllable from the userspace, and that
commit is annoying TOMOYO users who want to use e.g. squashfs as the root
filesystem due to use of local name which does not start with '/'.

Therefore, based on an assumption that filesystems which require the
device argument upon mount() request is an indication that the content
is controllable from the userspace, do not use local name if a filesystem
does not support rename() operation but requires the device argument upon
mount() request.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jamorris@linux.microsoft.com>
2019-05-10 14:58:30 -07:00
Tetsuo Handa e6193f78bb tomoyo: Check address length before reading address family
KMSAN will complain if valid address length passed to bind()/connect()/
sendmsg() is shorter than sizeof("struct sockaddr"->sa_family) bytes.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jamorris@linux.microsoft.com>
2019-05-10 14:58:25 -07:00
Tetsuo Handa e80b18599a tomoyo: Add a kernel config option for fuzzing testing.
syzbot is reporting kernel panic triggered by memory allocation fault
injection before loading TOMOYO's policy [1]. To make the fuzzing tests
useful, we need to assign a profile other than "disabled" (no-op) mode.
Therefore, let's allow syzbot to load TOMOYO's built-in policy for
"learning" mode using a kernel config option. This option must not be
enabled for kernels built for production system, for this option also
disables domain/program checks when modifying policy configuration via
/sys/kernel/security/tomoyo/ interface.

[1] https://syzkaller.appspot.com/bug?extid=29569ed06425fcf67a95

Reported-by: syzbot <syzbot+e1b8084e532b6ee7afab@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+29569ed06425fcf67a95@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+2ee3f8974c2e7dc69feb@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jamorris@linux.microsoft.com>
2019-05-10 14:58:11 -07:00
Tetsuo Handa 861f4bcffc tomoyo: Bump version.
Update URLs and profile version.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-02-19 14:17:25 -08:00
Tetsuo Handa 4b42564181 tomoyo: Allow multiple use_group lines.
Being able to specify multiple "use_group" lines makes it
easier to write whitelisted policies.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-01-24 14:50:27 -08:00
Tetsuo Handa cdcf6723ad tomoyo: Coding style fix.
Follow many of recommendations by scripts/checkpatch.pl, and follow
"lift switch variables out of switches" by Kees Cook.
This patch makes no functional change.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-01-24 14:50:27 -08:00
Tetsuo Handa 8c6cb983cd tomoyo: Swicth from cred->security to task_struct->security.
TOMOYO security module is designed to use "struct task_struct"->security
in order to allow per "struct task_struct" tracking without being disturbed
by unable to update "struct cred"->security due to override mechanism.

Now that infrastructure-managed security blob is ready, this patch updates
TOMOYO to use "struct task_struct"->security.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-01-23 11:36:15 -08:00
Tetsuo Handa 1cfb2a512e LSM: Make lsm_early_cred() and lsm_early_task() local functions.
Since current->cred == current->real_cred when ordered_lsm_init()
is called, and lsm_early_cred()/lsm_early_task() need to be called
between the amount of required bytes is determined and module specific
initialization function is called, we can move these calls from
individual modules to ordered_lsm_init().

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-01-18 11:44:02 -08:00
Kees Cook a5e2fe7ede TOMOYO: Update LSM flags to no longer be exclusive
With blob sharing in place, TOMOYO is no longer an exclusive LSM, so it
can operate separately now. Mark it as such.

Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-08 13:18:45 -08:00
Casey Schaufler bbd3662a83 Infrastructure management of the cred security blob
Move management of the cred security blob out of the
security modules and into the security infrastructre.
Instead of allocating and freeing space the security
modules tell the infrastructure how much space they
require.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
[kees: adjusted for ordered init series]
Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-08 13:18:44 -08:00
Casey Schaufler 43fc460907 TOMOYO: Abstract use of cred security blob
Don't use the cred->security pointer directly.
Provide helper functions that provide the security blob pointer.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
[kees: adjusted for ordered init series]
Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-08 13:18:44 -08:00
Kees Cook 14bd99c821 LSM: Separate idea of "major" LSM from "exclusive" LSM
In order to both support old "security=" Legacy Major LSM selection, and
handling real exclusivity, this creates LSM_FLAG_EXCLUSIVE and updates
the selection logic to handle them.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
2019-01-08 13:18:43 -08:00
Kees Cook f4941d75b9 LSM: Lift LSM selection out of individual LSMs
As a prerequisite to adjusting LSM selection logic in the future, this
moves the selection logic up out of the individual major LSMs, making
their init functions only run when actually enabled. This considers all
LSMs enabled by default unless they specified an external "enable"
variable.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
2019-01-08 13:18:42 -08:00
Kees Cook 47008e5161 LSM: Introduce LSM_FLAG_LEGACY_MAJOR
This adds a flag for the current "major" LSMs to distinguish them when
we have a universal method for ordering all LSMs. It's called "legacy"
since the distinction of "major" will go away in the blob-sharing world.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
2019-01-08 13:18:42 -08:00
Linus Torvalds 505b050fdf Merge branch 'mount.part1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs mount API prep from Al Viro:
 "Mount API prereqs.

  Mostly that's LSM mount options cleanups. There are several minor
  fixes in there, but nothing earth-shattering (leaks on failure exits,
  mostly)"

* 'mount.part1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (27 commits)
  mount_fs: suppress MAC on MS_SUBMOUNT as well as MS_KERNMOUNT
  smack: rewrite smack_sb_eat_lsm_opts()
  smack: get rid of match_token()
  smack: take the guts of smack_parse_opts_str() into a new helper
  LSM: new method: ->sb_add_mnt_opt()
  selinux: rewrite selinux_sb_eat_lsm_opts()
  selinux: regularize Opt_... names a bit
  selinux: switch away from match_token()
  selinux: new helper - selinux_add_opt()
  LSM: bury struct security_mnt_opts
  smack: switch to private smack_mnt_opts
  selinux: switch to private struct selinux_mnt_opts
  LSM: hide struct security_mnt_opts from any generic code
  selinux: kill selinux_sb_get_mnt_opts()
  LSM: turn sb_eat_lsm_opts() into a method
  nfs_remount(): don't leak, don't ignore LSM options quietly
  btrfs: sanitize security_mnt_opts use
  selinux; don't open-code a loop in sb_finish_set_opts()
  LSM: split ->sb_set_mnt_opts() out of ->sb_kern_mount()
  new helper: security_sb_eat_lsm_opts()
  ...
2019-01-05 13:25:58 -08:00
Linus Torvalds 96d4f267e4 Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-03 18:57:57 -08:00
David Howells e262e32d6b vfs: Suppress MS_* flag defs within the kernel unless explicitly enabled
Only the mount namespace code that implements mount(2) should be using the
MS_* flags.  Suppress them inside the kernel unless uapi/linux/mount.h is
included.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: David Howells <dhowells@redhat.com>
2018-12-20 16:32:56 +00:00
Yangtao Li f09c296ebf tomoyo: fix small typo
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-11-05 08:50:11 -08:00
Kees Cook 07aed2f2af LSM: Record LSM name in struct lsm_info
In preparation for making LSM selections outside of the LSMs, include
the name of LSMs in struct lsm_info.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-10 20:40:22 -07:00
Kees Cook 3d6e5f6dcf LSM: Convert security_initcall() into DEFINE_LSM()
Instead of using argument-based initializers, switch to defining the
contents of struct lsm_info on a per-LSM basis. This also drops
the final use of the now inaccurate "initcall" naming.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: James Morris <james.morris@microsoft.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-10 20:40:21 -07:00