Return directly after a call of the function "next_entry" failed
at the beginning.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

The script "checkpatch.pl" pointed information out like the following.

WARNING: void function return statements are not generally useful

Thus remove such a statement in the affected function.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

Multiplications for the size determination of memory allocations
indicated that array data structures should be processed.
Thus use the corresponding function "kcalloc".

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

The script "checkpatch.pl" pointed information out like the following.

Comparison to NULL could be written !…

Thus fix affected source code places.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kmalloc_array".

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

Replace the specification of data structures by pointer dereferences
as the parameter for the operator "sizeof" to make the corresponding size
determination a bit safer.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

The script "checkpatch.pl" pointed information out like the following.

WARNING: void function return statements are not generally useful

Thus remove such a statement in the affected function.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

* A multiplication for the size determination of a memory allocation
  indicated that an array data structure should be processed.
  Thus use the corresponding function "kmalloc_array".

  This issue was detected by using the Coccinelle software.

* Replace the specification of a data type by a pointer dereference
  to make the corresponding size determination a bit safer according to
  the Linux coding style convention.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

KMSAN (KernelMemorySanitizer, a new error detection tool) reports use of
uninitialized memory in selinux_socket_bind():

==================================================================
BUG: KMSAN: use of unitialized memory
inter: 0
CPU: 3 PID: 1074 Comm: packet2 Tainted: G    B           4.8.0-rc6+ #1916
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 0000000000000000 ffff8800882ffb08 ffffffff825759c8 ffff8800882ffa48
 ffffffff818bf551 ffffffff85bab870 0000000000000092 ffffffff85bab550
 0000000000000000 0000000000000092 00000000bb0009bb 0000000000000002
Call Trace:
 [<     inline     >] __dump_stack lib/dump_stack.c:15
 [<ffffffff825759c8>] dump_stack+0x238/0x290 lib/dump_stack.c:51
 [<ffffffff818bdee6>] kmsan_report+0x276/0x2e0 mm/kmsan/kmsan.c:1008
 [<ffffffff818bf0fb>] __msan_warning+0x5b/0xb0 mm/kmsan/kmsan_instr.c:424
 [<ffffffff822dae71>] selinux_socket_bind+0xf41/0x1080 security/selinux/hooks.c:4288
 [<ffffffff8229357c>] security_socket_bind+0x1ec/0x240 security/security.c:1240
 [<ffffffff84265d98>] SYSC_bind+0x358/0x5f0 net/socket.c:1366
 [<ffffffff84265a22>] SyS_bind+0x82/0xa0 net/socket.c:1356
 [<ffffffff81005678>] do_syscall_64+0x58/0x70 arch/x86/entry/common.c:292
 [<ffffffff8518217c>] entry_SYSCALL64_slow_path+0x25/0x25 arch/x86/entry/entry_64.o:?
chained origin: 00000000ba6009bb
 [<ffffffff810bb7a7>] save_stack_trace+0x27/0x50 arch/x86/kernel/stacktrace.c:67
 [<     inline     >] kmsan_save_stack_with_flags mm/kmsan/kmsan.c:322
 [<     inline     >] kmsan_save_stack mm/kmsan/kmsan.c:337
 [<ffffffff818bd2b8>] kmsan_internal_chain_origin+0x118/0x1e0 mm/kmsan/kmsan.c:530
 [<ffffffff818bf033>] __msan_set_alloca_origin4+0xc3/0x130 mm/kmsan/kmsan_instr.c:380
 [<ffffffff84265b69>] SYSC_bind+0x129/0x5f0 net/socket.c:1356
 [<ffffffff84265a22>] SyS_bind+0x82/0xa0 net/socket.c:1356
 [<ffffffff81005678>] do_syscall_64+0x58/0x70 arch/x86/entry/common.c:292
 [<ffffffff8518217c>] return_from_SYSCALL_64+0x0/0x6a arch/x86/entry/entry_64.o:?
origin description: ----address@SYSC_bind (origin=00000000b8c00900)
==================================================================

(the line numbers are relative to 4.8-rc6, but the bug persists upstream)

, when I run the following program as root:

=======================================================
  #include <string.h>
  #include <sys/socket.h>
  #include <netinet/in.h>

  int main(int argc, char *argv[]) {
    struct sockaddr addr;
    int size = 0;
    if (argc > 1) {
      size = atoi(argv[1]);
    }
    memset(&addr, 0, sizeof(addr));
    int fd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
    bind(fd, &addr, size);
    return 0;
  }
=======================================================

(for different values of |size| other error reports are printed).

This happens because bind() unconditionally copies |size| bytes of
|addr| to the kernel, leaving the rest uninitialized. Then
security_socket_bind() reads the IP address bytes, including the
uninitialized ones, to determine the port, or e.g. pass them further to
sel_netnode_find(), which uses them to calculate a hash.
Signed-off-by: NAlexander Potapenko <glider@google.com>
Acked-by: NEric Dumazet <edumazet@google.com>
[PM: fixed some whitespace damage]
Signed-off-by: NPaul Moore <paul@paul-moore.com>

Constify nlmsg permission tables, which are initialized once
and then do not change.
Signed-off-by: NJames Morris <james.l.morris@oracle.com>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

Mark all of the registration hooks as __ro_after_init (via the
__lsm_ro_after_init macro).
Signed-off-by: NJames Morris <james.l.morris@oracle.com>
Acked-by: NStephen Smalley <sds@tycho.nsa.gov>
Acked-by: NKees Cook <keescook@chromium.org>

Subsequent patches will add RO hardening to LSM hooks, however, SELinux
still needs to be able to perform runtime disablement after init to handle
architectures where init-time disablement via boot parameters is not feasible.

Introduce a new kernel configuration parameter CONFIG_SECURITY_WRITABLE_HOOKS,
and a helper macro __lsm_ro_after_init, to handle this case.
Signed-off-by: NJames Morris <james.l.morris@oracle.com>
Acked-by: NStephen Smalley <sds@tycho.nsa.gov>
Acked-by: NCasey Schaufler <casey@schaufler-ca.com>
Acked-by: NKees Cook <keescook@chromium.org>

commit 79bcf325e6b32b3c ("prlimit,security,selinux: add a security hook
for prlimit") introduced a security hook for prlimit() and implemented it
for SELinux.  However, if prlimit() is called with NULL arguments for both
the new limit and the old limit, then the hook is called with 0 for the
read/write flags, since the prlimit() will neither read nor write the
process' limits.  This would in turn lead to calling avc_has_perm() with 0
for the requested permissions, which triggers a BUG_ON() in
avc_has_perm_noaudit() since the kernel should never be invoking
avc_has_perm() with no permissions.  Fix this in the SELinux hook by
returning immediately if the flags are 0.  Arguably prlimit64() itself
ought to return immediately if both old_rlim and new_rlim are NULL since
it is effectively a no-op in that case.

Reported by the lkp-robot based on trinity testing.
Signed-off-by: NStephen Smalley <sds@tycho.nsa.gov>
Acked-by: NPaul Moore <paul@paul-moore.com>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

When SELinux was first added to the kernel, a process could only get
and set its own resource limits via getrlimit(2) and setrlimit(2), so no
MAC checks were required for those operations, and thus no security hooks
were defined for them. Later, SELinux introduced a hook for setlimit(2)
with a check if the hard limit was being changed in order to be able to
rely on the hard limit value as a safe reset point upon context
transitions.

Later on, when prlimit(2) was added to the kernel with the ability to get
or set resource limits (hard or soft) of another process, LSM/SELinux was
not updated other than to pass the target process to the setrlimit hook.
This resulted in incomplete control over both getting and setting the
resource limits of another process.

Add a new security_task_prlimit() hook to the check_prlimit_permission()
function to provide complete mediation.  The hook is only called when
acting on another task, and only if the existing DAC/capability checks
would allow access.  Pass flags down to the hook to indicate whether the
prlimit(2) call will read, write, or both read and write the resource
limits of the target process.

The existing security_task_setrlimit() hook is left alone; it continues
to serve a purpose in supporting the ability to make decisions based on
the old and/or new resource limit values when setting limits.  This
is consistent with the DAC/capability logic, where
check_prlimit_permission() performs generic DAC/capability checks for
acting on another task, while do_prlimit() performs a capability check
based on a comparison of the old and new resource limits.  Fix the
inline documentation for the hook to match the code.

Implement the new hook for SELinux.  For setting resource limits, we
reuse the existing setrlimit permission.  Note that this does overload
the setrlimit permission to mean the ability to set the resource limit
(soft or hard) of another process or the ability to change one's own
hard limit.  For getting resource limits, a new getrlimit permission
is defined.  This was not originally defined since getrlimit(2) could
only be used to obtain a process' own limits.
Signed-off-by: NStephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

Update files that depend on the magic.h inclusion.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

We don't actually need the full rculist.h header in sched.h anymore,
we will be able to include the smaller rcupdate.h header instead.

But first update code that relied on the implicit header inclusion.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

We are going to split <linux/sched/task.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/task.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Add #include <linux/cred.h> dependencies to all .c files rely on sched.h
doing that for them.

Note that even if the count where we need to add extra headers seems high,
it's still a net win, because <linux/sched.h> is included in over
2,200 files ...
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

We are going to split <linux/sched/user.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/user.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/signal.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

commit 1ea0ce40 ("selinux: allow
changing labels for cgroupfs") broke the Android init program,
which looks up security contexts whenever creating directories
and attempts to assign them via setfscreatecon().
When creating subdirectories in cgroup mounts, this would previously
be ignored since cgroup did not support userspace setting of security
contexts.  However, after the commit, SELinux would attempt to honor
the requested context on cgroup directories and fail due to permission
denial.  Avoid breaking existing userspace/policy by wrapping this change
with a conditional on a new cgroup_seclabel policy capability.  This
preserves existing behavior until/unless a new policy explicitly enables
this capability.
Reported-by: NJohn Stultz <john.stultz@linaro.org>
Signed-off-by: NStephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: NPaul Moore <paul@paul-moore.com>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

rcu_dereference_key() and user_key_payload() are currently being used in
two different, incompatible ways:

 (1) As a wrapper to rcu_dereference() - when only the RCU read lock used
     to protect the key.

 (2) As a wrapper to rcu_dereference_protected() - when the key semaphor is
     used to protect the key and the may be being modified.

Fix this by splitting both of the key wrappers to produce:

 (1) RCU accessors for keys when caller has the key semaphore locked:

	dereference_key_locked()
	user_key_payload_locked()

 (2) RCU accessors for keys when caller holds the RCU read lock:

	dereference_key_rcu()
	user_key_payload_rcu()

This should fix following warning in the NFS idmapper

  ===============================
  [ INFO: suspicious RCU usage. ]
  4.10.0 #1 Tainted: G        W
  -------------------------------
  ./include/keys/user-type.h:53 suspicious rcu_dereference_protected() usage!
  other info that might help us debug this:
  rcu_scheduler_active = 2, debug_locks = 0
  1 lock held by mount.nfs/5987:
    #0:  (rcu_read_lock){......}, at: [<d000000002527abc>] nfs_idmap_get_key+0x15c/0x420 [nfsv4]
  stack backtrace:
  CPU: 1 PID: 5987 Comm: mount.nfs Tainted: G        W       4.10.0 #1
  Call Trace:
    dump_stack+0xe8/0x154 (unreliable)
    lockdep_rcu_suspicious+0x140/0x190
    nfs_idmap_get_key+0x380/0x420 [nfsv4]
    nfs_map_name_to_uid+0x2a0/0x3b0 [nfsv4]
    decode_getfattr_attrs+0xfac/0x16b0 [nfsv4]
    decode_getfattr_generic.constprop.106+0xbc/0x150 [nfsv4]
    nfs4_xdr_dec_lookup_root+0xac/0xb0 [nfsv4]
    rpcauth_unwrap_resp+0xe8/0x140 [sunrpc]
    call_decode+0x29c/0x910 [sunrpc]
    __rpc_execute+0x140/0x8f0 [sunrpc]
    rpc_run_task+0x170/0x200 [sunrpc]
    nfs4_call_sync_sequence+0x68/0xa0 [nfsv4]
    _nfs4_lookup_root.isra.44+0xd0/0xf0 [nfsv4]
    nfs4_lookup_root+0xe0/0x350 [nfsv4]
    nfs4_lookup_root_sec+0x70/0xa0 [nfsv4]
    nfs4_find_root_sec+0xc4/0x100 [nfsv4]
    nfs4_proc_get_rootfh+0x5c/0xf0 [nfsv4]
    nfs4_get_rootfh+0x6c/0x190 [nfsv4]
    nfs4_server_common_setup+0xc4/0x260 [nfsv4]
    nfs4_create_server+0x278/0x3c0 [nfsv4]
    nfs4_remote_mount+0x50/0xb0 [nfsv4]
    mount_fs+0x74/0x210
    vfs_kern_mount+0x78/0x220
    nfs_do_root_mount+0xb0/0x140 [nfsv4]
    nfs4_try_mount+0x60/0x100 [nfsv4]
    nfs_fs_mount+0x5ec/0xda0 [nfs]
    mount_fs+0x74/0x210
    vfs_kern_mount+0x78/0x220
    do_mount+0x254/0xf70
    SyS_mount+0x94/0x100
    system_call+0x38/0xe0
Reported-by: NJan Stancek <jstancek@redhat.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Tested-by: NJan Stancek <jstancek@redhat.com>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

Now that %z is standartised in C99 there is no reason to support %Z.
Unlike %L it doesn't even make format strings smaller.

Use BUILD_BUG_ON in a couple ATM drivers.

In case anyone didn't notice lib/vsprintf.o is about half of SLUB which
is in my opinion is quite an achievement.  Hopefully this patch inspires
someone else to trim vsprintf.c more.

Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to
take a vma and vmf parameter when the vma already resides in vmf.

Remove the vma parameter to simplify things.

[arnd@arndb.de: fix ARM build]
  Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.comSigned-off-by: NDave Jiang <dave.jiang@intel.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NRoss Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I don't think GCC has figured out how to optimize the memset() away, but
they might eventually so let's future proof this code a bit.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

This function has two callers and neither are able to handle a NULL
return.  Really, -EINVAL is the correct thing return here anyway.  This
fixes some static checker warnings like:

	security/keys/encrypted-keys/encrypted.c:709 encrypted_key_decrypt()
	error: uninitialized symbol 'master_key'.

Fixes: 7e70cb49 ("keys: add new key-type encrypted")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

SELinux tries to support setting/clearing of /proc/pid/attr attributes
from the shell by ignoring terminating newlines and treating an
attribute value that begins with a NUL or newline as an attempt to
clear the attribute.  However, the test for clearing attributes has
always been wrong; it has an off-by-one error, and this could further
lead to reading past the end of the allocated buffer since commit
bb646cdb ("proc_pid_attr_write():
switch to memdup_user()").  Fix the off-by-one error.

Even with this fix, setting and clearing /proc/pid/attr attributes
from the shell is not straightforward since the interface does not
support multiple write() calls (so shells that write the value and
newline separately will set and then immediately clear the attribute,
requiring use of echo -n to set the attribute), whereas trying to use
echo -n "" to clear the attribute causes the shell to skip the
write() call altogether since POSIX says that a zero-length write
causes no side effects. Thus, one must use echo -n to set and echo
without -n to clear, as in the following example:
$ echo -n unconfined_u:object_r:user_home_t:s0 > /proc/$$/attr/fscreate
$ cat /proc/$$/attr/fscreate
unconfined_u:object_r:user_home_t:s0
$ echo "" > /proc/$$/attr/fscreate
$ cat /proc/$$/attr/fscreate

Note the use of /proc/$$ rather than /proc/self, as otherwise
the cat command will read its own attribute value, not that of the shell.

There are no users of this facility to my knowledge; possibly we
should just get rid of it.

UPDATE: Upon further investigation it appears that a local process
with the process:setfscreate permission can cause a kernel panic as a
result of this bug.  This patch fixes CVE-2017-2618.
Signed-off-by: NStephen Smalley <sds@tycho.nsa.gov>
[PM: added the update about CVE-2017-2618 to the commit description]
Cc: stable@vger.kernel.org # 3.5: d6ea83ecSigned-off-by: NPaul Moore <paul@paul-moore.com>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

This patch allows changing labels for cgroup mounts. Previously, running
chcon on cgroupfs would throw an "Operation not supported". This patch
specifically whitelist cgroupfs.

The patch could also allow containers to write only to the systemd cgroup
for instance, while the other cgroups are kept with cgroup_t label.
Signed-off-by: NAntonio Murdaca <runcom@redhat.com>
Acked-by: NStephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

SELinux tries to support setting/clearing of /proc/pid/attr attributes
from the shell by ignoring terminating newlines and treating an
attribute value that begins with a NUL or newline as an attempt to
clear the attribute.  However, the test for clearing attributes has
always been wrong; it has an off-by-one error, and this could further
lead to reading past the end of the allocated buffer since commit
bb646cdb ("proc_pid_attr_write():
switch to memdup_user()").  Fix the off-by-one error.

Even with this fix, setting and clearing /proc/pid/attr attributes
from the shell is not straightforward since the interface does not
support multiple write() calls (so shells that write the value and
newline separately will set and then immediately clear the attribute,
requiring use of echo -n to set the attribute), whereas trying to use
echo -n "" to clear the attribute causes the shell to skip the
write() call altogether since POSIX says that a zero-length write
causes no side effects. Thus, one must use echo -n to set and echo
without -n to clear, as in the following example:
$ echo -n unconfined_u:object_r:user_home_t:s0 > /proc/$$/attr/fscreate
$ cat /proc/$$/attr/fscreate
unconfined_u:object_r:user_home_t:s0
$ echo "" > /proc/$$/attr/fscreate
$ cat /proc/$$/attr/fscreate

Note the use of /proc/$$ rather than /proc/self, as otherwise
the cat command will read its own attribute value, not that of the shell.

There are no users of this facility to my knowledge; possibly we
should just get rid of it.

UPDATE: Upon further investigation it appears that a local process
with the process:setfscreate permission can cause a kernel panic as a
result of this bug.  This patch fixes CVE-2017-2618.
Signed-off-by: NStephen Smalley <sds@tycho.nsa.gov>
[PM: added the update about CVE-2017-2618 to the commit description]
Cc: stable@vger.kernel.org # 3.5: d6ea83ecSigned-off-by: NPaul Moore <paul@paul-moore.com>

Otherwise some mask and inmask tokens with MAY_APPEND flag may not work
as expected.
Signed-off-by: NLans Zhang <jia.zhang@windriver.com>
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>

On failure to return a pathname from ima_d_path(), a pointer to
dname is returned, which is subsequently used in the IMA measurement
list, the IMA audit records, and other audit logging.  Saving the
pointer to dname for later use has the potential to race with rename.

Intead of returning a pointer to dname on failure, this patch returns
a pointer to a copy of the filename.
Reported-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org

Add net.ipv4.ip_unprivileged_port_start, which is a per namespace sysctl
that denotes the first unprivileged inet port in the namespace.  To
disable all privileged ports set this to zero.  It also checks for
overlap with the local port range.  The privileged and local range may
not overlap.

The use case for this change is to allow containerized processes to bind
to priviliged ports, but prevent them from ever being allowed to modify
their container's network configuration.  The latter is accomplished by
ensuring that the network namespace is not a child of the user
namespace.  This modification was needed to allow the container manager
to disable a namespace's priviliged port restrictions without exposing
control of the network namespace to processes in the user namespace.
Signed-off-by: NKrister Johansen <kjlx@templeofstupid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With previous changes every location that tests for
LSM_UNSAFE_PTRACE_CAP also tests for LSM_UNSAFE_PTRACE making the
LSM_UNSAFE_PTRACE_CAP redundant, so remove it.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Now that we have user namespaces and non-global capabilities verify
the tracer has capabilities in the relevant user namespace instead
of in the current_user_ns().

As the test for setting LSM_UNSAFE_PTRACE_CAP is currently
ptracer_capable(p, current_user_ns()) and the new task credentials are
in current_user_ns() this change does not have any user visible change
and simply moves the test to where it is used, making the code easier
to read.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Don't reset euid and egid when the tracee has CAP_SETUID in
it's user namespace.  I punted on relaxing this permission check
long ago but now that I have read this code closely it is clear
it is safe to test against CAP_SETUID in the user namespace.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Some usermode helper applications are defined at kernel build time, while
others can be changed at runtime.  To provide a sane way to filter these, add a
new kernel option "STATIC_USERMODEHELPER".  This option routes all
call_usermodehelper() calls through this binary, no matter what the caller
wishes to have called.

The new binary (by default set to /sbin/usermode-helper, but can be changed
through the STATIC_USERMODEHELPER_PATH option) can properly filter the
requested programs to be run by the kernel by looking at the first argument
that is passed to it.  All other options should then be passed onto the proper
program if so desired.

To disable all call_usermodehelper() calls by the kernel, set
STATIC_USERMODEHELPER_PATH to an empty string.

Thanks to Neil Brown for the idea of this feature.

Cc: NeilBrown <neilb@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There are a number of usermode helper binaries that are "hard coded" in
the kernel today, so mark them as "const" to make it harder for someone
to change where the variables point to.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Sailer <t.sailer@alumni.ethz.ch>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alex Elder <elder@kernel.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@poochiereds.net>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

I am still tired of having to find indirect ways to determine
what security modules are active on a system. I have added
/sys/kernel/security/lsm, which contains a comma separated
list of the active security modules. No more groping around
in /proc/filesystems or other clever hacks.

Unchanged from previous versions except for being updated
to the latest security next branch.
Signed-off-by: NCasey Schaufler <casey@schaufler-ca.com>
Acked-by: NJohn Johansen <john.johansen@canonical.com>
Acked-by: NPaul Moore <paul@paul-moore.com>
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

The kernel build bot turned up a bad config combination when
CONFIG_SECURITY_APPARMOR is y and CONFIG_SECURITY_APPARMOR_HASH is n,
resulting in the build error
   security/built-in.o: In function `aa_unpack':
   (.text+0x841e2): undefined reference to `aa_g_hash_policy'
Signed-off-by: NJohn Johansen <john.johansen@canonical.com>

AA_BUG() uses WARN and won't break the kernel like BUG_ON().
Signed-off-by: NJohn Johansen <john.johansen@canonical.com>