Commit Graph

2752 Commits

Author SHA1 Message Date
David Howells
096fe9eaea KEYS: Fix handling of stored error in a negatively instantiated user key
If a user key gets negatively instantiated, an error code is cached in the
payload area.  A negatively instantiated key may be then be positively
instantiated by updating it with valid data.  However, the ->update key
type method must be aware that the error code may be there.

The following may be used to trigger the bug in the user key type:

    keyctl request2 user user "" @u
    keyctl add user user "a" @u

which manifests itself as:

	BUG: unable to handle kernel paging request at 00000000ffffff8a
	IP: [<ffffffff810a376f>] __call_rcu.constprop.76+0x1f/0x280 kernel/rcu/tree.c:3046
	PGD 7cc30067 PUD 0
	Oops: 0002 [#1] SMP
	Modules linked in:
	CPU: 3 PID: 2644 Comm: a.out Not tainted 4.3.0+ #49
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
	task: ffff88003ddea700 ti: ffff88003dd88000 task.ti: ffff88003dd88000
	RIP: 0010:[<ffffffff810a376f>]  [<ffffffff810a376f>] __call_rcu.constprop.76+0x1f/0x280
	 [<ffffffff810a376f>] __call_rcu.constprop.76+0x1f/0x280 kernel/rcu/tree.c:3046
	RSP: 0018:ffff88003dd8bdb0  EFLAGS: 00010246
	RAX: 00000000ffffff82 RBX: 0000000000000000 RCX: 0000000000000001
	RDX: ffffffff81e3fe40 RSI: 0000000000000000 RDI: 00000000ffffff82
	RBP: ffff88003dd8bde0 R08: ffff88007d2d2da0 R09: 0000000000000000
	R10: 0000000000000000 R11: ffff88003e8073c0 R12: 00000000ffffff82
	R13: ffff88003dd8be68 R14: ffff88007d027600 R15: ffff88003ddea700
	FS:  0000000000b92880(0063) GS:ffff88007fd00000(0000) knlGS:0000000000000000
	CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
	CR2: 00000000ffffff8a CR3: 000000007cc5f000 CR4: 00000000000006e0
	Stack:
	 ffff88003dd8bdf0 ffffffff81160a8a 0000000000000000 00000000ffffff82
	 ffff88003dd8be68 ffff88007d027600 ffff88003dd8bdf0 ffffffff810a39e5
	 ffff88003dd8be20 ffffffff812a31ab ffff88007d027600 ffff88007d027620
	Call Trace:
	 [<ffffffff810a39e5>] kfree_call_rcu+0x15/0x20 kernel/rcu/tree.c:3136
	 [<ffffffff812a31ab>] user_update+0x8b/0xb0 security/keys/user_defined.c:129
	 [<     inline     >] __key_update security/keys/key.c:730
	 [<ffffffff8129e5c1>] key_create_or_update+0x291/0x440 security/keys/key.c:908
	 [<     inline     >] SYSC_add_key security/keys/keyctl.c:125
	 [<ffffffff8129fc21>] SyS_add_key+0x101/0x1e0 security/keys/keyctl.c:60
	 [<ffffffff8185f617>] entry_SYSCALL_64_fastpath+0x12/0x6a arch/x86/entry/entry_64.S:185

Note the error code (-ENOKEY) in EDX.

A similar bug can be tripped by:

    keyctl request2 trusted user "" @u
    keyctl add trusted user "a" @u

This should also affect encrypted keys - but that has to be correctly
parameterised or it will fail with EINVAL before getting to the bit that
will crashes.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-11-25 14:19:47 +11:00
Stephen Smalley
f3bef67992 selinux: fix bug in conditional rules handling
commit fa1aa143ac ("selinux: extended permissions for ioctls")
introduced a bug into the handling of conditional rules, skipping the
processing entirely when the caller does not provide an extended
permissions (xperms) structure.  Access checks from userspace using
/sys/fs/selinux/access do not include such a structure since that
interface does not presently expose extended permission information.
As a result, conditional rules were being ignored entirely on userspace
access requests, producing denials when access was allowed by
conditional rules in the policy.  Fix the bug by only skipping
computation of extended permissions in this situation, not the entire
conditional rules processing.

Reported-by: Laurent Bigonville <bigon@debian.org>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: fixed long lines in patch description]
Cc: stable@vger.kernel.org # 4.3
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-11-24 13:44:32 -05:00
Dmitry Kasatkin
f4dc37785e integrity: define '.evm' as a builtin 'trusted' keyring
Require all keys added to the EVM keyring be signed by an
existing trusted key on the system trusted keyring.

This patch also switches IMA to use integrity_init_keyring().

Changes in v3:
* Added 'init_keyring' config based variable to skip initializing
  keyring instead of using  __integrity_init_keyring() wrapper.
* Added dependency back to CONFIG_IMA_TRUSTED_KEYRING

Changes in v2:
* Replace CONFIG_EVM_TRUSTED_KEYRING with IMA and EVM common
  CONFIG_INTEGRITY_TRUSTED_KEYRING configuration option
* Deprecate CONFIG_IMA_TRUSTED_KEYRING but keep it for config
  file compatibility. (Mimi Zohar)

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-11-23 14:30:02 -05:00
Linus Torvalds
2df4ee78d0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix null deref in xt_TEE netfilter module, from Eric Dumazet.

 2) Several spots need to get to the original listner for SYN-ACK
    packets, most spots got this ok but some were not.  Whilst covering
    the remaining cases, create a helper to do this.  From Eric Dumazet.

 3) Missiing check of return value from alloc_netdev() in CAIF SPI code,
    from Rasmus Villemoes.

 4) Don't sleep while != TASK_RUNNING in macvtap, from Vlad Yasevich.

 5) Use after free in mvneta driver, from Justin Maggard.

 6) Fix race on dst->flags access in dst_release(), from Eric Dumazet.

 7) Add missing ZLIB_INFLATE dependency for new qed driver.  From Arnd
    Bergmann.

 8) Fix multicast getsockopt deadlock, from WANG Cong.

 9) Fix deadlock in btusb, from Kuba Pawlak.

10) Some ipv6_add_dev() failure paths were not cleaning up the SNMP6
    counter state.  From Sabrina Dubroca.

11) Fix packet_bind() race, which can cause lost notifications, from
    Francesco Ruggeri.

12) Fix MAC restoration in qlcnic driver during bonding mode changes,
    from Jarod Wilson.

13) Revert bridging forward delay change which broke libvirt and other
    userspace things, from Vlad Yasevich.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (65 commits)
  Revert "bridge: Allow forward delay to be cfgd when STP enabled"
  bpf_trace: Make dependent on PERF_EVENTS
  qed: select ZLIB_INFLATE
  net: fix a race in dst_release()
  net: mvneta: Fix memory use after free.
  net: Documentation: Fix default value tcp_limit_output_bytes
  macvtap: Resolve possible __might_sleep warning in macvtap_do_read()
  mvneta: add FIXED_PHY dependency
  net: caif: check return value of alloc_netdev
  net: hisilicon: NET_VENDOR_HISILICON should depend on HAS_DMA
  drivers: net: xgene: fix RGMII 10/100Mb mode
  netfilter: nft_meta: use skb_to_full_sk() helper
  net_sched: em_meta: use skb_to_full_sk() helper
  sched: cls_flow: use skb_to_full_sk() helper
  netfilter: xt_owner: use skb_to_full_sk() helper
  smack: use skb_to_full_sk() helper
  net: add skb_to_full_sk() helper and use it in selinux_netlbl_skbuff_setsid()
  bpf: doc: correct arch list for supported eBPF JIT
  dwc_eth_qos: Delete an unnecessary check before the function call "of_node_put"
  bonding: fix panic on non-ARPHRD_ETHER enslave failure
  ...
2015-11-10 18:11:41 -08:00
Eric Dumazet
8827d90e29 smack: use skb_to_full_sk() helper
This module wants to access sk->sk_security, which is not
available for request sockets.

Fixes: ca6fb06518 ("tcp: attach SYNACK messages to request sockets instead of listener")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-08 20:56:38 -05:00
Eric Dumazet
54abc686c2 net: add skb_to_full_sk() helper and use it in selinux_netlbl_skbuff_setsid()
Generalize selinux_skb_sk() added in commit 212cd08953
("selinux: fix random read in selinux_ip_postroute_compat()")
so that we can use it other contexts.

Use it right away in selinux_netlbl_skbuff_setsid()

Fixes: ca6fb06518 ("tcp: attach SYNACK messages to request sockets instead of listener")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-08 20:56:38 -05:00
Mel Gorman
71baba4b92 mm, page_alloc: rename __GFP_WAIT to __GFP_RECLAIM
__GFP_WAIT was used to signal that the caller was in atomic context and
could not sleep.  Now it is possible to distinguish between true atomic
context and callers that are not willing to sleep.  The latter should
clear __GFP_DIRECT_RECLAIM so kswapd will still wake.  As clearing
__GFP_WAIT behaves differently, there is a risk that people will clear the
wrong flags.  This patch renames __GFP_WAIT to __GFP_RECLAIM to clearly
indicate what it does -- setting it allows all reclaim activity, clearing
them prevents it.

[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 17:50:42 -08:00
Linus Torvalds
1873499e13 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem update from James Morris:
 "This is mostly maintenance updates across the subsystem, with a
  notable update for TPM 2.0, and addition of Jarkko Sakkinen as a
  maintainer of that"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (40 commits)
  apparmor: clarify CRYPTO dependency
  selinux: Use a kmem_cache for allocation struct file_security_struct
  selinux: ioctl_has_perm should be static
  selinux: use sprintf return value
  selinux: use kstrdup() in security_get_bools()
  selinux: use kmemdup in security_sid_to_context_core()
  selinux: remove pointless cast in selinux_inode_setsecurity()
  selinux: introduce security_context_str_to_sid
  selinux: do not check open perm on ftruncate call
  selinux: change CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE default
  KEYS: Merge the type-specific data with the payload data
  KEYS: Provide a script to extract a module signature
  KEYS: Provide a script to extract the sys cert list from a vmlinux file
  keys: Be more consistent in selection of union members used
  certs: add .gitignore to stop git nagging about x509_certificate_list
  KEYS: use kvfree() in add_key
  Smack: limited capability for changing process label
  TPM: remove unnecessary little endian conversion
  vTPM: support little endian guests
  char: Drop owner assignment from i2c_driver
  ...
2015-11-05 15:32:38 -08:00
Eric Dumazet
212cd08953 selinux: fix random read in selinux_ip_postroute_compat()
In commit e446f9dfe1 ("net: synack packets can be attached to request
sockets"), I missed one remaining case of invalid skb->sk->sk_security
access.

Dmitry Vyukov got a KASan report pointing to it.

Add selinux_skb_sk() helper that is responsible to get back to the
listener if skb is attached to a request socket, instead of
duplicating the logic.

Fixes: ca6fb06518 ("tcp: attach SYNACK messages to request sockets instead of listener")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-05 16:45:51 -05:00
David S. Miller
b75ec3af27 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-11-01 00:15:30 -04:00
James Morris
ba94c3ff20 Merge tag 'keys-next-20151021' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs into next 2015-10-23 12:07:52 +11:00
James Morris
a47c7a6c8a Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/selinux into next 2015-10-22 11:17:50 +11:00
Arnd Bergmann
083c1290ca apparmor: clarify CRYPTO dependency
The crypto framework can be built as a loadable module, but the
apparmor hash code can only be built-in, which then causes a
link error:

security/built-in.o: In function `aa_calc_profile_hash':
integrity_audit.c:(.text+0x21610): undefined reference to `crypto_shash_update'
security/built-in.o: In function `init_profile_hash':
integrity_audit.c:(.init.text+0xb4c): undefined reference to `crypto_alloc_shash'

This changes Apparmor to use 'select CRYPTO' like a lot of other
subsystems do.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-10-22 11:11:28 +11:00
Sangwoo
63205654c0 selinux: Use a kmem_cache for allocation struct file_security_struct
The size of struct file_security_struct is 16byte at my setup.
But, the real allocation size for per each file_security_struct
is 64bytes in my setup that kmalloc min size is 64bytes
because ARCH_DMA_MINALIGN is 64.

This allocation is called every times at file allocation(alloc_file()).
So, the total slack memory size(allocated size - request size)
is increased exponentially.

E.g) Min Kmalloc Size : 64bytes, Unit : bytes
      Allocated Size | Request Size | Slack Size | Allocation Count
    ---------------------------------------------------------------
         770048      |    192512    |   577536   |      12032

At the result, this change reduce memory usage 42bytes per each
file_security_struct

Signed-off-by: Sangwoo <sangwoo2.park@lge.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: removed extra subject prefix]
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-10-21 17:44:30 -04:00
Geliang Tang
1d2a168a08 selinux: ioctl_has_perm should be static
Fixes the following sparse warning:

 security/selinux/hooks.c:3242:5: warning: symbol 'ioctl_has_perm' was
 not declared. Should it be static?

Signed-off-by: Geliang Tang <geliangtang@163.com>
Acked-by: Jeff Vander Stoep <jeffv@google.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-10-21 17:44:27 -04:00
Rasmus Villemoes
9529c7886c selinux: use sprintf return value
sprintf returns the number of characters printed (excluding '\0'), so
we can use that and avoid duplicating the length computation.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-10-21 17:44:27 -04:00
Rasmus Villemoes
21b76f199e selinux: use kstrdup() in security_get_bools()
This is much simpler.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-10-21 17:44:26 -04:00
Rasmus Villemoes
aa736c36db selinux: use kmemdup in security_sid_to_context_core()
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-10-21 17:44:26 -04:00
Rasmus Villemoes
20ba96aeeb selinux: remove pointless cast in selinux_inode_setsecurity()
security_context_to_sid() expects a const char* argument, so there's
no point in casting away the const qualifier of value.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-10-21 17:44:26 -04:00
Rasmus Villemoes
44be2f65d9 selinux: introduce security_context_str_to_sid
There seems to be a little confusion as to whether the scontext_len
parameter of security_context_to_sid() includes the nul-byte or
not. Reading security_context_to_sid_core(), it seems that the
expectation is that it does not (both the string copying and the test
for scontext_len being zero hint at that).

Introduce the helper security_context_str_to_sid() to do the strlen()
call and fix all callers.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-10-21 17:44:25 -04:00
Jeff Vander Stoep
44d37ad360 selinux: do not check open perm on ftruncate call
Use the ATTR_FILE attribute to distinguish between truncate()
and ftruncate() system calls. The two other cases where
do_truncate is called with a filp (and therefore ATTR_FILE is set)
are for coredump files and for open(O_TRUNC). In both of those cases
the open permission has already been checked during file open and
therefore does not need to be repeated.

Commit 95dbf73931 ("SELinux: check OPEN on truncate calls")
fixed a major issue where domains were allowed to truncate files
without the open permission. However, it introduced a new bug where
a domain with the write permission can no longer ftruncate files
without the open permission, even when they receive an already open
file.

Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-10-21 17:44:25 -04:00
Paul Moore
2a35d196c1 selinux: change CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE default
Change the SELinux checkreqprot default value to 0 so that SELinux
performs access control checking on the actual memory protections
used by the kernel and not those requested by the application.

Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-10-21 17:44:25 -04:00
David Howells
146aa8b145 KEYS: Merge the type-specific data with the payload data
Merge the type-specific data with the payload data into one four-word chunk
as it seems pointless to keep them separate.

Use user_key_payload() for accessing the payloads of overloaded
user-defined keys.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-cifs@vger.kernel.org
cc: ecryptfs@vger.kernel.org
cc: linux-ext4@vger.kernel.org
cc: linux-f2fs-devel@lists.sourceforge.net
cc: linux-nfs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: linux-ima-devel@lists.sourceforge.net
2015-10-21 15:18:36 +01:00
Insu Yun
27720e75a7 keys: Be more consistent in selection of union members used
key->description and key->index_key.description are same because
they are unioned. But, for readability, using same name for
duplication and validation seems better.

Signed-off-by: Insu Yun <wuninsu@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2015-10-21 15:18:35 +01:00
Geliang Tang
d0e0eba043 KEYS: use kvfree() in add_key
There is no need to make a flag to tell that this memory is allocated by
kmalloc or vmalloc. Just use kvfree to free the memory.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2015-10-21 15:18:35 +01:00
James Morris
09302fd19e Merge branch 'smack-for-4.4' of https://github.com/cschaufler/smack-next into next 2015-10-21 10:49:29 +11:00
James Morris
fbf9826589 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into next 2015-10-20 12:34:04 +11:00
Zbigniew Jasinski
38416e5393 Smack: limited capability for changing process label
This feature introduces new kernel interface:

- <smack_fs>/relabel-self - for setting transition labels list

This list is used to control smack label transition mechanism.
List is set by, and per process. Process can transit to new label only if
label is on the list. Only process with CAP_MAC_ADMIN capability can add
labels to this list. With this list, process can change it's label without
CAP_MAC_ADMIN but only once. After label changing, list is unset.

Changes in v2:
* use list_for_each_entry instead of _rcu during label write
* added missing description in security/Smack.txt

Changes in v3:
* squashed into one commit

Changes in v4:
* switch from global list to per-task list
* since the per-task list is accessed only by the task itself
  there is no need to use synchronization mechanisms on it

Changes in v5:
* change smackfs interface of relabel-self to the one used for onlycap
  multiple labels are accepted, separated by space, which
  replace the previous list upon write

Signed-off-by: Zbigniew Jasinski <z.jasinski@samsung.com>
Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2015-10-19 12:06:47 -07:00
David Howells
911b79cde9 KEYS: Don't permit request_key() to construct a new keyring
If request_key() is used to find a keyring, only do the search part - don't
do the construction part if the keyring was not found by the search.  We
don't really want keyrings in the negative instantiated state since the
rejected/negative instantiation error value in the payload is unioned with
keyring metadata.

Now the kernel gives an error:

	request_key("keyring", "#selinux,bdekeyring", "keyring", KEY_SPEC_USER_SESSION_KEYRING) = -1 EPERM (Operation not permitted)

Signed-off-by: David Howells <dhowells@redhat.com>
2015-10-19 11:24:51 +01:00
Jarkko Sakkinen
0fe5480303 keys, trusted: seal/unseal with TPM 2.0 chips
Call tpm_seal_trusted() and tpm_unseal_trusted() for TPM 2.0 chips.
We require explicit 'keyhandle=' option because there's no a fixed
storage root key inside TPM2 chips.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Andreas Fuchs <andreas.fuchs@sit.fraunhofer.de>
Tested-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (on TPM 1.2)
Tested-by: Chris J Arges <chris.j.arges@canonical.com>
Tested-by: Colin Ian King <colin.king@canonical.com>
Tested-by: Kevin Strasser <kevin.strasser@intel.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2015-10-19 01:01:22 +02:00
Jarkko Sakkinen
fe351e8d4e keys, trusted: move struct trusted_key_options to trusted-type.h
Moved struct trusted_key_options to trustes-type.h so that the fields
can be accessed from drivers/char/tpm.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2015-10-19 01:01:21 +02:00
Pablo Neira Ayuso
f0a0a978b6 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
This merge resolves conflicts with 75aec9df3a ("bridge: Remove
br_nf_push_frag_xmit_sk") as part of Eric Biederman's effort to improve
netns support in the network stack that reached upstream via David's
net-next tree.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Conflicts:
	net/bridge/br_netfilter_hooks.c
2015-10-17 14:28:03 +02:00
Florian Westphal
2ffbceb2b0 netfilter: remove hook owner refcounting
since commit 8405a8fff3 ("netfilter: nf_qeueue: Drop queue entries on
nf_unregister_hook") all pending queued entries are discarded.

So we can simply remove all of the owner handling -- when module is
removed it also needs to unregister all its hooks.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-10-16 18:21:39 +02:00
David Howells
f05819df10 KEYS: Fix crash when attempt to garbage collect an uninstantiated keyring
The following sequence of commands:

    i=`keyctl add user a a @s`
    keyctl request2 keyring foo bar @t
    keyctl unlink $i @s

tries to invoke an upcall to instantiate a keyring if one doesn't already
exist by that name within the user's keyring set.  However, if the upcall
fails, the code sets keyring->type_data.reject_error to -ENOKEY or some
other error code.  When the key is garbage collected, the key destroy
function is called unconditionally and keyring_destroy() uses list_empty()
on keyring->type_data.link - which is in a union with reject_error.
Subsequently, the kernel tries to unlink the keyring from the keyring names
list - which oopses like this:

	BUG: unable to handle kernel paging request at 00000000ffffff8a
	IP: [<ffffffff8126e051>] keyring_destroy+0x3d/0x88
	...
	Workqueue: events key_garbage_collector
	...
	RIP: 0010:[<ffffffff8126e051>] keyring_destroy+0x3d/0x88
	RSP: 0018:ffff88003e2f3d30  EFLAGS: 00010203
	RAX: 00000000ffffff82 RBX: ffff88003bf1a900 RCX: 0000000000000000
	RDX: 0000000000000000 RSI: 000000003bfc6901 RDI: ffffffff81a73a40
	RBP: ffff88003e2f3d38 R08: 0000000000000152 R09: 0000000000000000
	R10: ffff88003e2f3c18 R11: 000000000000865b R12: ffff88003bf1a900
	R13: 0000000000000000 R14: ffff88003bf1a908 R15: ffff88003e2f4000
	...
	CR2: 00000000ffffff8a CR3: 000000003e3ec000 CR4: 00000000000006f0
	...
	Call Trace:
	 [<ffffffff8126c756>] key_gc_unused_keys.constprop.1+0x5d/0x10f
	 [<ffffffff8126ca71>] key_garbage_collector+0x1fa/0x351
	 [<ffffffff8105ec9b>] process_one_work+0x28e/0x547
	 [<ffffffff8105fd17>] worker_thread+0x26e/0x361
	 [<ffffffff8105faa9>] ? rescuer_thread+0x2a8/0x2a8
	 [<ffffffff810648ad>] kthread+0xf3/0xfb
	 [<ffffffff810647ba>] ? kthread_create_on_node+0x1c2/0x1c2
	 [<ffffffff815f2ccf>] ret_from_fork+0x3f/0x70
	 [<ffffffff810647ba>] ? kthread_create_on_node+0x1c2/0x1c2

Note the value in RAX.  This is a 32-bit representation of -ENOKEY.

The solution is to only call ->destroy() if the key was successfully
instantiated.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
2015-10-15 17:21:37 +01:00
Eric Dumazet
e446f9dfe1 net: synack packets can be attached to request sockets
selinux needs few changes to accommodate fact that SYNACK messages
can be attached to a request socket, lacking sk_security pointer

(Only syncookies are still attached to a TCP_LISTEN socket)

Adds a new sk_listener() helper, and use it in selinux and sch_fq

Fixes: ca6fb06518 ("tcp: attach SYNACK messages to request sockets instead of listener")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported by: kernel test robot <ying.huang@linux.intel.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Eric Paris <eparis@parisplace.org>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-11 05:05:06 -07:00
Roman Kubiak
8da4aba5bf Smack: pipefs fix in smack_d_instantiate
This fix writes the task label when
smack_d_instantiate is called, before the
label of the superblock was written on the
pipe's inode.

Signed-off-by: Roman Kubiak <r.kubiak@samsung.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2015-10-09 15:13:41 -07:00
José Bollo
d21b7b049c Smack: Minor initialisation improvement
This change has two goals:
 - delay the setting of 'smack_enabled' until
   it will be really effective
 - ensure that smackfs is valid only if 'smack_enabled'
   is set (it is already the case in smack_netfilter.c)

Signed-off-by: José Bollo <jose.bollo@iot.bzh>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2015-10-09 15:13:24 -07:00
Geliang Tang
8b549ef42a smack: smk_ipv6_port_list should be static
Fixes the following sparse warning:

 security/smack/smack_lsm.c:55:1: warning: symbol 'smk_ipv6_port_list'
 was not declared. Should it be static?

Signed-off-by: Geliang Tang <geliangtang@163.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2015-10-09 15:13:08 -07:00
Lukasz Pawelczyk
5f2bfe2f1d Smack: fix a NULL dereference in wrong smack_import_entry() usage
'commit e774ad683f ("smack: pass error code through pointers")'
made this function return proper error codes instead of NULL. Reflect that.

This is a fix for a NULL dereference introduced in
'commit 21abb1ec41 ("Smack: IPv6 host labeling")'

echo "$SOME_IPV6_ADDR \"test" > /smack/ipv6host
  (this should return EINVAL, it doesn't)
cat /smack/ipv6host
  (derefences 0x000a)

Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@samsung.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2015-10-09 15:12:46 -07:00
Dmitry Kasatkin
72e1eed8ab integrity: prevent loading untrusted certificates on the IMA trusted keyring
If IMA_LOAD_X509 is enabled, either directly or indirectly via
IMA_APPRAISE_SIGNED_INIT, certificates are loaded onto the IMA
trusted keyring by the kernel via key_create_or_update(). When
the KEY_ALLOC_TRUSTED flag is provided, certificates are loaded
without first verifying the certificate is properly signed by a
trusted key on the system keyring.  This patch removes the
KEY_ALLOC_TRUSTED flag.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Cc:  <stable@vger.kernel.org> # 3.19+
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-10-09 15:31:18 -04:00
David S. Miller
f6d3125fa3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/dsa/slave.c

net/dsa/slave.c simply had overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-02 07:21:25 -07:00
David S. Miller
4963ed48f2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/ipv4/arp.c

The net/ipv4/arp.c conflict was one commit adding a new
local variable while another commit was deleting one.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-26 16:08:27 -07:00
David Howells
94c4554ba0 KEYS: Fix race between key destruction and finding a keyring by name
There appears to be a race between:

 (1) key_gc_unused_keys() which frees key->security and then calls
     keyring_destroy() to unlink the name from the name list

 (2) find_keyring_by_name() which calls key_permission(), thus accessing
     key->security, on a key before checking to see whether the key usage is 0
     (ie. the key is dead and might be cleaned up).

Fix this by calling ->destroy() before cleaning up the core key data -
including key->security.

Reported-by: Petr Matousek <pmatouse@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2015-09-25 16:30:08 +01:00
Eric W. Biederman
06198b34a3 netfilter: Pass priv instead of nf_hook_ops to netfilter hooks
Only pass the void *priv parameter out of the nf_hook_ops.  That is
all any of the functions are interested now, and by limiting what is
passed it becomes simpler to change implementation details.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 22:00:16 +02:00
Linus Torvalds
1b3dfde386 Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU fix from Ingo Molnar:
 "Fix a false positive warning"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  security/device_cgroup: Fix RCU_LOCKDEP_WARN() condition
2015-09-17 08:44:27 -07:00
Ingo Molnar
31409c9764 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent
Pull RCU fix from Paul E. McKenney, fixing an inverted RCU_LOCKDEP_WARN() condition.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-12 10:26:24 +02:00
Kirill A. Shutemov
7cbea8dc01 mm: mark most vm_operations_struct const
With two exceptions (drm/qxl and drm/radeon) all vm_operations_struct
structs should be constant.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10 13:29:01 -07:00
Linus Torvalds
b793c005ce Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "Highlights:

   - PKCS#7 support added to support signed kexec, also utilized for
     module signing.  See comments in 3f1e1bea.

     ** NOTE: this requires linking against the OpenSSL library, which
        must be installed, e.g.  the openssl-devel on Fedora **

   - Smack
      - add IPv6 host labeling; ignore labels on kernel threads
      - support smack labeling mounts which use binary mount data

   - SELinux:
      - add ioctl whitelisting (see
        http://kernsec.org/files/lss2015/vanderstoep.pdf)
      - fix mprotect PROT_EXEC regression caused by mm change

   - Seccomp:
      - add ptrace options for suspend/resume"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (57 commits)
  PKCS#7: Add OIDs for sha224, sha284 and sha512 hash algos and use them
  Documentation/Changes: Now need OpenSSL devel packages for module signing
  scripts: add extract-cert and sign-file to .gitignore
  modsign: Handle signing key in source tree
  modsign: Use if_changed rule for extracting cert from module signing key
  Move certificate handling to its own directory
  sign-file: Fix warning about BIO_reset() return value
  PKCS#7: Add MODULE_LICENSE() to test module
  Smack - Fix build error with bringup unconfigured
  sign-file: Document dependency on OpenSSL devel libraries
  PKCS#7: Appropriately restrict authenticated attributes and content type
  KEYS: Add a name for PKEY_ID_PKCS7
  PKCS#7: Improve and export the X.509 ASN.1 time object decoder
  modsign: Use extract-cert to process CONFIG_SYSTEM_TRUSTED_KEYS
  extract-cert: Cope with multiple X.509 certificates in a single file
  sign-file: Generate CMS message as signature instead of PKCS#7
  PKCS#7: Support CMS messages also [RFC5652]
  X.509: Change recorded SKID & AKID to not include Subject or Issuer
  PKCS#7: Check content type and versions
  MAINTAINERS: The keyrings mailing list has moved
  ...
2015-09-08 12:41:25 -07:00
Kees Cook
a068acf2ee fs: create and use seq_show_option for escaping
Many file systems that implement the show_options hook fail to correctly
escape their output which could lead to unescaped characters (e.g.  new
lines) leaking into /proc/mounts and /proc/[pid]/mountinfo files.  This
could lead to confusion, spoofed entries (resulting in things like
systemd issuing false d-bus "mount" notifications), and who knows what
else.  This looks like it would only be the root user stepping on
themselves, but it's possible weird things could happen in containers or
in other situations with delegated mount privileges.

Here's an example using overlay with setuid fusermount trusting the
contents of /proc/mounts (via the /etc/mtab symlink).  Imagine the use
of "sudo" is something more sneaky:

  $ BASE="ovl"
  $ MNT="$BASE/mnt"
  $ LOW="$BASE/lower"
  $ UP="$BASE/upper"
  $ WORK="$BASE/work/ 0 0
  none /proc fuse.pwn user_id=1000"
  $ mkdir -p "$LOW" "$UP" "$WORK"
  $ sudo mount -t overlay -o "lowerdir=$LOW,upperdir=$UP,workdir=$WORK" none /mnt
  $ cat /proc/mounts
  none /root/ovl/mnt overlay rw,relatime,lowerdir=ovl/lower,upperdir=ovl/upper,workdir=ovl/work/ 0 0
  none /proc fuse.pwn user_id=1000 0 0
  $ fusermount -u /proc
  $ cat /proc/mounts
  cat: /proc/mounts: No such file or directory

This fixes the problem by adding new seq_show_option and
seq_show_option_n helpers, and updating the vulnerable show_option
handlers to use them as needed.  Some, like SELinux, need to be open
coded due to unusual existing escape mechanisms.

[akpm@linux-foundation.org: add lost chunk, per Kees]
[keescook@chromium.org: seq_show_option should be using const parameters]
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Jan Kara <jack@suse.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Cc: J. R. Okajima <hooanon05g@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Andy Lutomirski
746bf6d642 capabilities: add a securebit to disable PR_CAP_AMBIENT_RAISE
Per Andrew Morgan's request, add a securebit to allow admins to disable
PR_CAP_AMBIENT_RAISE.  This securebit will prevent processes from adding
capabilities to their ambient set.

For simplicity, this disables PR_CAP_AMBIENT_RAISE entirely rather than
just disabling setting previously cleared bits.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Andrew G. Morgan <morgan@kernel.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Aaron Jones <aaronmdjones@gmail.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Andrew G. Morgan <morgan@kernel.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Austin S Hemmelgarn <ahferroin7@gmail.com>
Cc: Markku Savela <msa@moth.iki.fi>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: James Morris <james.l.morris@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Andy Lutomirski
58319057b7 capabilities: ambient capabilities
Credit where credit is due: this idea comes from Christoph Lameter with
a lot of valuable input from Serge Hallyn.  This patch is heavily based
on Christoph's patch.

===== The status quo =====

On Linux, there are a number of capabilities defined by the kernel.  To
perform various privileged tasks, processes can wield capabilities that
they hold.

Each task has four capability masks: effective (pE), permitted (pP),
inheritable (pI), and a bounding set (X).  When the kernel checks for a
capability, it checks pE.  The other capability masks serve to modify
what capabilities can be in pE.

Any task can remove capabilities from pE, pP, or pI at any time.  If a
task has a capability in pP, it can add that capability to pE and/or pI.
If a task has CAP_SETPCAP, then it can add any capability to pI, and it
can remove capabilities from X.

Tasks are not the only things that can have capabilities; files can also
have capabilities.  A file can have no capabilty information at all [1].
If a file has capability information, then it has a permitted mask (fP)
and an inheritable mask (fI) as well as a single effective bit (fE) [2].
File capabilities modify the capabilities of tasks that execve(2) them.

A task that successfully calls execve has its capabilities modified for
the file ultimately being excecuted (i.e.  the binary itself if that
binary is ELF or for the interpreter if the binary is a script.) [3] In
the capability evolution rules, for each mask Z, pZ represents the old
value and pZ' represents the new value.  The rules are:

  pP' = (X & fP) | (pI & fI)
  pI' = pI
  pE' = (fE ? pP' : 0)
  X is unchanged

For setuid binaries, fP, fI, and fE are modified by a moderately
complicated set of rules that emulate POSIX behavior.  Similarly, if
euid == 0 or ruid == 0, then fP, fI, and fE are modified differently
(primary, fP and fI usually end up being the full set).  For nonroot
users executing binaries with neither setuid nor file caps, fI and fP
are empty and fE is false.

As an extra complication, if you execute a process as nonroot and fE is
set, then the "secure exec" rules are in effect: AT_SECURE gets set,
LD_PRELOAD doesn't work, etc.

This is rather messy.  We've learned that making any changes is
dangerous, though: if a new kernel version allows an unprivileged
program to change its security state in a way that persists cross
execution of a setuid program or a program with file caps, this
persistent state is surprisingly likely to allow setuid or file-capped
programs to be exploited for privilege escalation.

===== The problem =====

Capability inheritance is basically useless.

If you aren't root and you execute an ordinary binary, fI is zero, so
your capabilities have no effect whatsoever on pP'.  This means that you
can't usefully execute a helper process or a shell command with elevated
capabilities if you aren't root.

On current kernels, you can sort of work around this by setting fI to
the full set for most or all non-setuid executable files.  This causes
pP' = pI for nonroot, and inheritance works.  No one does this because
it's a PITA and it isn't even supported on most filesystems.

If you try this, you'll discover that every nonroot program ends up with
secure exec rules, breaking many things.

This is a problem that has bitten many people who have tried to use
capabilities for anything useful.

===== The proposed change =====

This patch adds a fifth capability mask called the ambient mask (pA).
pA does what most people expect pI to do.

pA obeys the invariant that no bit can ever be set in pA if it is not
set in both pP and pI.  Dropping a bit from pP or pI drops that bit from
pA.  This ensures that existing programs that try to drop capabilities
still do so, with a complication.  Because capability inheritance is so
broken, setting KEEPCAPS, using setresuid to switch to nonroot uids, and
then calling execve effectively drops capabilities.  Therefore,
setresuid from root to nonroot conditionally clears pA unless
SECBIT_NO_SETUID_FIXUP is set.  Processes that don't like this can
re-add bits to pA afterwards.

The capability evolution rules are changed:

  pA' = (file caps or setuid or setgid ? 0 : pA)
  pP' = (X & fP) | (pI & fI) | pA'
  pI' = pI
  pE' = (fE ? pP' : pA')
  X is unchanged

If you are nonroot but you have a capability, you can add it to pA.  If
you do so, your children get that capability in pA, pP, and pE.  For
example, you can set pA = CAP_NET_BIND_SERVICE, and your children can
automatically bind low-numbered ports.  Hallelujah!

Unprivileged users can create user namespaces, map themselves to a
nonzero uid, and create both privileged (relative to their namespace)
and unprivileged process trees.  This is currently more or less
impossible.  Hallelujah!

You cannot use pA to try to subvert a setuid, setgid, or file-capped
program: if you execute any such program, pA gets cleared and the
resulting evolution rules are unchanged by this patch.

Users with nonzero pA are unlikely to unintentionally leak that
capability.  If they run programs that try to drop privileges, dropping
privileges will still work.

It's worth noting that the degree of paranoia in this patch could
possibly be reduced without causing serious problems.  Specifically, if
we allowed pA to persist across executing non-pA-aware setuid binaries
and across setresuid, then, naively, the only capabilities that could
leak as a result would be the capabilities in pA, and any attacker
*already* has those capabilities.  This would make me nervous, though --
setuid binaries that tried to privilege-separate might fail to do so,
and putting CAP_DAC_READ_SEARCH or CAP_DAC_OVERRIDE into pA could have
unexpected side effects.  (Whether these unexpected side effects would
be exploitable is an open question.) I've therefore taken the more
paranoid route.  We can revisit this later.

An alternative would be to require PR_SET_NO_NEW_PRIVS before setting
ambient capabilities.  I think that this would be annoying and would
make granting otherwise unprivileged users minor ambient capabilities
(CAP_NET_BIND_SERVICE or CAP_NET_RAW for example) much less useful than
it is with this patch.

===== Footnotes =====

[1] Files that are missing the "security.capability" xattr or that have
unrecognized values for that xattr end up with has_cap set to false.
The code that does that appears to be complicated for no good reason.

[2] The libcap capability mask parsers and formatters are dangerously
misleading and the documentation is flat-out wrong.  fE is *not* a mask;
it's a single bit.  This has probably confused every single person who
has tried to use file capabilities.

[3] Linux very confusingly processes both the script and the interpreter
if applicable, for reasons that elude me.  The results from thinking
about a script's file capabilities and/or setuid bits are mostly
discarded.

Preliminary userspace code is here, but it needs updating:
https://git.kernel.org/cgit/linux/kernel/git/luto/util-linux-playground.git/commit/?h=cap_ambient&id=7f5afbd175d2

Here is a test program that can be used to verify the functionality
(from Christoph):

/*
 * Test program for the ambient capabilities. This program spawns a shell
 * that allows running processes with a defined set of capabilities.
 *
 * (C) 2015 Christoph Lameter <cl@linux.com>
 * Released under: GPL v3 or later.
 *
 *
 * Compile using:
 *
 *	gcc -o ambient_test ambient_test.o -lcap-ng
 *
 * This program must have the following capabilities to run properly:
 * Permissions for CAP_NET_RAW, CAP_NET_ADMIN, CAP_SYS_NICE
 *
 * A command to equip the binary with the right caps is:
 *
 *	setcap cap_net_raw,cap_net_admin,cap_sys_nice+p ambient_test
 *
 *
 * To get a shell with additional caps that can be inherited by other processes:
 *
 *	./ambient_test /bin/bash
 *
 *
 * Verifying that it works:
 *
 * From the bash spawed by ambient_test run
 *
 *	cat /proc/$$/status
 *
 * and have a look at the capabilities.
 */

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <cap-ng.h>
#include <sys/prctl.h>
#include <linux/capability.h>

/*
 * Definitions from the kernel header files. These are going to be removed
 * when the /usr/include files have these defined.
 */
#define PR_CAP_AMBIENT 47
#define PR_CAP_AMBIENT_IS_SET 1
#define PR_CAP_AMBIENT_RAISE 2
#define PR_CAP_AMBIENT_LOWER 3
#define PR_CAP_AMBIENT_CLEAR_ALL 4

static void set_ambient_cap(int cap)
{
	int rc;

	capng_get_caps_process();
	rc = capng_update(CAPNG_ADD, CAPNG_INHERITABLE, cap);
	if (rc) {
		printf("Cannot add inheritable cap\n");
		exit(2);
	}
	capng_apply(CAPNG_SELECT_CAPS);

	/* Note the two 0s at the end. Kernel checks for these */
	if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_RAISE, cap, 0, 0)) {
		perror("Cannot set cap");
		exit(1);
	}
}

int main(int argc, char **argv)
{
	int rc;

	set_ambient_cap(CAP_NET_RAW);
	set_ambient_cap(CAP_NET_ADMIN);
	set_ambient_cap(CAP_SYS_NICE);

	printf("Ambient_test forking shell\n");
	if (execv(argv[1], argv + 1))
		perror("Cannot exec");

	return 0;
}

Signed-off-by: Christoph Lameter <cl@linux.com> # Original author
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Aaron Jones <aaronmdjones@gmail.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Andrew G. Morgan <morgan@kernel.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Austin S Hemmelgarn <ahferroin7@gmail.com>
Cc: Markku Savela <msa@moth.iki.fi>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: James Morris <james.l.morris@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Paul E. McKenney
dc3a04d551 security/device_cgroup: Fix RCU_LOCKDEP_WARN() condition
f78f5b90c4 ("rcu: Rename rcu_lockdep_assert() to RCU_LOCKDEP_WARN()")
introduced a bug by incorrectly inverting the condition when moving from
rcu_lockdep_assert() to RCU_LOCKDEP_WARN().  This commit therefore fixes
the inversion.

Reported-by: Felipe Balbi <balbi@ti.com>
Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Tested-by: Josh Boyer <jwboyer@fedoraproject.org>
2015-09-03 18:13:10 -07:00
Linus Torvalds
73b6fa8e49 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace updates from Eric Biederman:
 "This finishes up the changes to ensure proc and sysfs do not start
  implementing executable files, as the there are application today that
  are only secure because such files do not exist.

  It akso fixes a long standing misfeature of /proc/<pid>/mountinfo that
  did not show the proper source for files bind mounted from
  /proc/<pid>/ns/*.

  It also straightens out the handling of clone flags related to user
  namespaces, fixing an unnecessary failure of unshare(CLONE_NEWUSER)
  when files such as /proc/<pid>/environ are read while <pid> is calling
  unshare.  This winds up fixing a minor bug in unshare flag handling
  that dates back to the first version of unshare in the kernel.

  Finally, this fixes a minor regression caused by the introduction of
  sysfs_create_mount_point, which broke someone's in house application,
  by restoring the size of /sys/fs/cgroup to 0 bytes.  Apparently that
  application uses the directory size to determine if a tmpfs is mounted
  on /sys/fs/cgroup.

  The bind mount escape fixes are present in Al Viros for-next branch.
  and I expect them to come from there.  The bind mount escape is the
  last of the user namespace related security bugs that I am aware of"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  fs: Set the size of empty dirs to 0.
  userns,pidns: Force thread group sharing, not signal handler sharing.
  unshare: Unsharing a thread does not require unsharing a vm
  nsfs: Add a show_path method to fix mountinfo
  mnt: fs_fully_visible enforce noexec and nosuid  if !SB_I_NOEXEC
  vfs: Commit to never having exectuables on proc and sysfs.
2015-09-01 16:13:25 -07:00
Linus Torvalds
7073bc6612 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main RCU changes in this cycle are:

   - the combination of tree geometry-initialization simplifications and
     OS-jitter-reduction changes to expedited grace periods.  These two
     are stacked due to the large number of conflicts that would
     otherwise result.

   - privatize smp_mb__after_unlock_lock().

     This commit moves the definition of smp_mb__after_unlock_lock() to
     kernel/rcu/tree.h, in recognition of the fact that RCU is the only
     thing using this, that nothing else is likely to use it, and that
     it is likely to go away completely.

   - documentation updates.

   - torture-test updates.

   - misc fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits)
  rcu,locking: Privatize smp_mb__after_unlock_lock()
  rcu: Silence lockdep false positive for expedited grace periods
  rcu: Don't disable CPU hotplug during OOM notifiers
  scripts: Make checkpatch.pl warn on expedited RCU grace periods
  rcu: Update MAINTAINERS entry
  rcu: Clarify CONFIG_RCU_EQS_DEBUG help text
  rcu: Fix backwards RCU_LOCKDEP_WARN() in synchronize_rcu_tasks()
  rcu: Rename rcu_lockdep_assert() to RCU_LOCKDEP_WARN()
  rcu: Make rcu_is_watching() really notrace
  cpu: Wait for RCU grace periods concurrently
  rcu: Create a synchronize_rcu_mult()
  rcu: Fix obsolete priority-boosting comment
  rcu: Use WRITE_ONCE in RCU_INIT_POINTER
  rcu: Hide RCU_NOCB_CPU behind RCU_EXPERT
  rcu: Add RCU-sched flavors of get-state and cond-sync
  rcu: Add fastpath bypassing funnel locking
  rcu: Rename RCU_GP_DONE_FQS to RCU_GP_DOING_FQS
  rcu: Pull out wait_event*() condition into helper function
  documentation: Describe new expedited stall warnings
  rcu: Add stall warnings to synchronize_sched_expedited()
  ...
2015-08-31 18:12:07 -07:00
Jan Beulich
e308fd3bb2 LSM: restore certain default error codes
While in most cases commit b1d9e6b064 ("LSM: Switch to lists of hooks")
retained previous error returns, in three cases it altered them without
any explanation in the commit message. Restore all of them - in the
security_old_inode_init_security() case this led to reiserfs using
uninitialized data, sooner or later crashing the system (the only other
user of this function - ocfs2 - was unaffected afaict, since it passes
pre-initialized structures).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-08-26 09:46:50 +10:00
James Morris
3e5f206c00 Merge branch 'next' of git://git.infradead.org/users/pcmoore/selinux into next 2015-08-15 13:29:57 +10:00
James Morris
0e38c35815 Merge branch 'smack-for-4.3' of https://github.com/cschaufler/smack-next into next 2015-08-14 17:35:10 +10:00
Casey Schaufler
3d04c92403 Smack - Fix build error with bringup unconfigured
The changes for mounting binary filesystems was allied
improperly, with the list of tokens being in an ifdef that
it shouldn't have been. Fix that, and a couple style issues
that were bothering me.

Reported-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2015-08-12 18:10:01 -07:00
Ingo Molnar
9b9412dc70 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU changes from Paul E. McKenney:

  - The combination of tree geometry-initialization simplifications
    and OS-jitter-reduction changes to expedited grace periods.
    These two are stacked due to the large number of conflicts
    that would otherwise result.

    [ With one addition, a temporary commit to silence a lockdep false
      positive. Additional changes to the expedited grace-period
      primitives (queued for 4.4) remove the cause of this false
      positive, and therefore include a revert of this temporary commit. ]

  - Documentation updates.

  - Torture-test updates.

  - Miscellaneous fixes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-12 12:12:12 +02:00
James Morris
5ab1657902 Merge branch 'smack-for-4.3' of https://github.com/cschaufler/smack-next into next 2015-08-11 11:18:53 +10:00
Roman Kubiak
41a2d57516 Kernel threads excluded from smack checks
Adds an ignore case for kernel tasks,
so that they can access all resources.

Since kernel worker threads are spawned with
floor label, they are severely restricted by
Smack policy. It is not an issue without onlycap,
as these processes also run with root,
so CAP_MAC_OVERRIDE kicks in. But with onlycap
turned on, there is no way to change the label
for these processes.

Signed-off-by: Roman Kubiak <r.kubiak@samsung.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2015-08-10 15:15:50 -07:00
Salvatore Mesoraca
5413fcdbe9 Adding YAMA hooks also when YAMA is not stacked.
Without this patch YAMA will not work at all if it is chosen
as the primary LSM instead of being "stacked".

Signed-off-by: Salvatore Mesoraca <s.mesoraca16@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-08-04 01:36:18 +10:00
Casey Schaufler
1eddfe8edb Smack: Three symbols that should be static
The kbuild test robot reported a couple of these,
and the third showed up by inspection. Making the
symbols static is proper.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2015-07-31 12:12:17 -07:00
Casey Schaufler
21abb1ec41 Smack: IPv6 host labeling
IPv6 appears to be (finally) coming of age with the
influx of autonomous devices. In support of this, add
the ability to associate a Smack label with IPv6 addresses.

This patch also cleans up some of the conditional
compilation associated with the introduction of
secmark processing. It's now more obvious which bit
of code goes with which feature.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2015-07-28 06:35:21 -07:00
Kees Cook
730daa164e Yama: remove needless CONFIG_SECURITY_YAMA_STACKED
Now that minor LSMs can cleanly stack with major LSMs, remove the unneeded
config for Yama to be made to explicitly stack. Just selecting the main
Yama CONFIG will allow it to work, regardless of the major LSM. Since
distros using Yama are already forcing it to stack, this is effectively
a no-op change.

Additionally add MAINTAINERS entry.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-07-28 13:18:19 +10:00
Colin Ian King
ca4da5dd1f KEYS: ensure we free the assoc array edit if edit is valid
__key_link_end is not freeing the associated array edit structure
and this leads to a 512 byte memory leak each time an identical
existing key is added with add_key().

The reason the add_key() system call returns okay is that
key_create_or_update() calls __key_link_begin() before checking to see
whether it can update a key directly rather than adding/replacing - which
it turns out it can.  Thus __key_link() is not called through
__key_instantiate_and_link() and __key_link_end() must cancel the edit.

CVE-2015-1333

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-07-28 13:08:23 +10:00
Paul E. McKenney
f78f5b90c4 rcu: Rename rcu_lockdep_assert() to RCU_LOCKDEP_WARN()
This commit renames rcu_lockdep_assert() to RCU_LOCKDEP_WARN() for
consistency with the WARN() series of macros.  This also requires
inverting the sense of the conditional, which this commit also does.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
2015-07-22 15:27:32 -07:00
kbuild test robot
ca70d27e44 sysfs: fix simple_return.cocci warnings
security/smack/smackfs.c:2251:1-4: WARNING: end returns can be
simpified and declaration on line 2250 can be dropped

 Simplify a trivial if-return sequence.  Possibly combine with a
 preceding function call.

Generated by: scripts/coccinelle/misc/simple_return.cocci

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2015-07-22 12:31:40 -07:00
Vivek Trivedi
3bf2789cad smack: allow mount opts setting over filesystems with binary mount data
Add support for setting smack mount labels(using smackfsdef, smackfsroot,
smackfshat, smackfsfloor, smackfstransmute) for filesystems with binary
mount data like NFS.

To achieve this, implement sb_parse_opts_str and sb_set_mnt_opts security
operations in smack LSM similar to SELinux.

Signed-off-by: Vivek Trivedi <t.vivek@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2015-07-22 12:31:28 -07:00
David Howells
c3c188b2c3 selinux: Create a common helper to determine an inode label [ver #3]
Create a common helper function to determine the label for a new inode.
This is then used by:

	- may_create()
	- selinux_dentry_init_security()
	- selinux_inode_init_security()

This will change the behaviour of the functions slightly, bringing them
all into line.

Suggested-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-07-13 13:31:59 -04:00
Stephen Smalley
bd1741f4cf selinux: Augment BUG_ON assertion for secclass_map.
Ensure that we catch any cases where tclass == 0.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-07-13 13:31:59 -04:00
Stephen Smalley
5dee25d08e selinux: initialize sock security class to default value
Initialize the security class of sock security structures
to the generic socket class.  This is similar to what is
already done in inode_alloc_security for files.  Generally
the sclass field will later by set by socket_post_create
or sk_clone or sock_graft, but for protocol implementations
that fail to call any of these for newly accepted sockets,
we want some sane default that will yield a legitimate
avc denied message with non-garbage values for class and
permission.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-07-13 13:31:59 -04:00
Waiman Long
9629d04ae0 selinux: reduce locking overhead in inode_free_security()
The inode_free_security() function just took the superblock's isec_lock
before checking and trying to remove the inode security struct from the
linked list. In many cases, the list was empty and so the lock taking
is wasteful as no useful work is done. On multi-socket systems with
a large number of CPUs, there can also be a fair amount of spinlock
contention on the isec_lock if many tasks are exiting at the same time.

This patch changes the code to check the state of the list first before
taking the lock and attempting to dequeue it. The list_del_init()
can be called more than once on the same list with no harm as long
as they are properly serialized. It should not be possible to have
inode_free_security() called concurrently with list_add(). For better
safety, however, we use list_empty_careful() here even though it is
still not completely safe in case that happens.

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-07-13 13:31:59 -04:00
Jeff Vander Stoep
fa1aa143ac selinux: extended permissions for ioctls
Add extended permissions logic to selinux. Extended permissions
provides additional permissions in 256 bit increments. Extend the
generic ioctl permission check to use the extended permissions for
per-command filtering. Source/target/class sets including the ioctl
permission may additionally include a set of commands. Example:

allowxperm <source> <target>:<class> ioctl unpriv_app_socket_cmds
auditallowxperm <source> <target>:<class> ioctl priv_gpu_cmds

Where unpriv_app_socket_cmds and priv_gpu_cmds are macros
representing commonly granted sets of ioctl commands.

When ioctl commands are omitted only the permissions are checked.
This feature is intended to provide finer granularity for the ioctl
permission that may be too imprecise. For example, the same driver
may use ioctls to provide important and benign functionality such as
driver version or socket type as well as dangerous capabilities such
as debugging features, read/write/execute to physical memory or
access to sensitive data. Per-command filtering provides a mechanism
to reduce the attack surface of the kernel, and limit applications
to the subset of commands required.

The format of the policy binary has been modified to include ioctl
commands, and the policy version number has been incremented to
POLICYDB_VERSION_XPERMS_IOCTL=30 to account for the format
change.

The extended permissions logic is deliberately generic to allow
components to be reused e.g. netlink filters

Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Acked-by: Nick Kralevich <nnk@google.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-07-13 13:31:58 -04:00
Jeff Vander Stoep
671a2781ff security: add ioctl specific auditing to lsm_audit
Add information about ioctl calls to the LSM audit data. Log the
file path and command number.

Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Acked-by: Nick Kralevich <nnk@google.com>
[PM: subject line tweak]
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-07-13 13:31:58 -04:00
James Morris
3dbbbe0eb6 Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/selinux into for-linus2 2015-07-11 09:13:45 +10:00
Stephen Smalley
892e8cac99 selinux: fix mprotect PROT_EXEC regression caused by mm change
commit 66fc130394 ("mm: shmem_zero_setup
skip security check and lockdep conflict with XFS") caused a regression
for SELinux by disabling any SELinux checking of mprotect PROT_EXEC on
shared anonymous mappings.  However, even before that regression, the
checking on such mprotect PROT_EXEC calls was inconsistent with the
checking on a mmap PROT_EXEC call for a shared anonymous mapping.  On a
mmap, the security hook is passed a NULL file and knows it is dealing
with an anonymous mapping and therefore applies an execmem check and no
file checks.  On a mprotect, the security hook is passed a vma with a
non-NULL vm_file (as this was set from the internally-created shmem
file during mmap) and therefore applies the file-based execute check
and no execmem check.  Since the aforementioned commit now marks the
shmem zero inode with the S_PRIVATE flag, the file checks are disabled
and we have no checking at all on mprotect PROT_EXEC.  Add a test to
the mprotect hook logic for such private inodes, and apply an execmem
check in that case.  This makes the mmap and mprotect checking
consistent for shared anonymous mappings, as well as for /dev/zero and
ashmem.

Cc: <stable@vger.kernel.org> # 4.1.x
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-07-10 16:45:29 -04:00
Eric W. Biederman
90f8572b0f vfs: Commit to never having exectuables on proc and sysfs.
Today proc and sysfs do not contain any executable files.  Several
applications today mount proc or sysfs without noexec and nosuid and
then depend on there being no exectuables files on proc or sysfs.
Having any executable files show on proc or sysfs would cause
a user space visible regression, and most likely security problems.

Therefore commit to never allowing executables on proc and sysfs by
adding a new flag to mark them as filesystems without executables and
enforce that flag.

Test the flag where MNT_NOEXEC is tested today, so that the only user
visible effect will be that exectuables will be treated as if the
execute bit is cleared.

The filesystems proc and sysfs do not currently incoporate any
executable files so this does not result in any user visible effects.

This makes it unnecessary to vet changes to proc and sysfs tightly for
adding exectuable files or changes to chattr that would modify
existing files, as no matter what the individual file say they will
not be treated as exectuable files by the vfs.

Not having to vet changes to closely is important as without this we
are only one proc_create call (or another goof up in the
implementation of notify_change) from having problematic executables
on proc.  Those mistakes are all too easy to make and would create
a situation where there are security issues or the assumptions of
some program having to be broken (and cause userspace regressions).

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-10 10:39:25 -05:00
Paul Moore
3324603524 selinux: don't waste ebitmap space when importing NetLabel categories
At present we don't create efficient ebitmaps when importing NetLabel
category bitmaps.  This can present a problem when comparing ebitmaps
since ebitmap_cmp() is very strict about these things and considers
these wasteful ebitmaps not equal when compared to their more
efficient counterparts, even if their values are the same.  This isn't
likely to cause problems on 64-bit systems due to a bit of luck on
how NetLabel/CIPSO works and the default ebitmap size, but it can be
a problem on 32-bit systems.

This patch fixes this problem by being a bit more intelligent when
importing NetLabel category bitmaps by skipping over empty sections
which should result in a nice, efficient ebitmap.

Cc: stable@vger.kernel.org # 3.17
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-07-09 14:20:36 -04:00
Linus Torvalds
1dc51b8288 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro:
 "Assorted VFS fixes and related cleanups (IMO the most interesting in
  that part are f_path-related things and Eric's descriptor-related
  stuff).  UFS regression fixes (it got broken last cycle).  9P fixes.
  fs-cache series, DAX patches, Jan's file_remove_suid() work"

[ I'd say this is much more than "fixes and related cleanups".  The
  file_table locking rule change by Eric Dumazet is a rather big and
  fundamental update even if the patch isn't huge.   - Linus ]

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits)
  9p: cope with bogus responses from server in p9_client_{read,write}
  p9_client_write(): avoid double p9_free_req()
  9p: forgetting to cancel request on interrupted zero-copy RPC
  dax: bdev_direct_access() may sleep
  block: Add support for DAX reads/writes to block devices
  dax: Use copy_from_iter_nocache
  dax: Add block size note to documentation
  fs/file.c: __fget() and dup2() atomicity rules
  fs/file.c: don't acquire files->file_lock in fd_install()
  fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
  vfs: avoid creation of inode number 0 in get_next_ino
  namei: make set_root_rcu() return void
  make simple_positive() public
  ufs: use dir_pages instead of ufs_dir_pages()
  pagemap.h: move dir_pages() over there
  remove the pointless include of lglock.h
  fs: cleanup slight list_entry abuse
  xfs: Correctly lock inode when removing suid and file capabilities
  fs: Call security_ops->inode_killpriv on truncate
  fs: Provide function telling whether file_remove_privs() will do anything
  ...
2015-07-04 19:36:06 -07:00
Linus Torvalds
0cbee99269 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace updates from Eric Biederman:
 "Long ago and far away when user namespaces where young it was realized
  that allowing fresh mounts of proc and sysfs with only user namespace
  permissions could violate the basic rule that only root gets to decide
  if proc or sysfs should be mounted at all.

  Some hacks were put in place to reduce the worst of the damage could
  be done, and the common sense rule was adopted that fresh mounts of
  proc and sysfs should allow no more than bind mounts of proc and
  sysfs.  Unfortunately that rule has not been fully enforced.

  There are two kinds of gaps in that enforcement.  Only filesystems
  mounted on empty directories of proc and sysfs should be ignored but
  the test for empty directories was insufficient.  So in my tree
  directories on proc, sysctl and sysfs that will always be empty are
  created specially.  Every other technique is imperfect as an ordinary
  directory can have entries added even after a readdir returns and
  shows that the directory is empty.  Special creation of directories
  for mount points makes the code in the kernel a smidge clearer about
  it's purpose.  I asked container developers from the various container
  projects to help test this and no holes were found in the set of mount
  points on proc and sysfs that are created specially.

  This set of changes also starts enforcing the mount flags of fresh
  mounts of proc and sysfs are consistent with the existing mount of
  proc and sysfs.  I expected this to be the boring part of the work but
  unfortunately unprivileged userspace winds up mounting fresh copies of
  proc and sysfs with noexec and nosuid clear when root set those flags
  on the previous mount of proc and sysfs.  So for now only the atime,
  read-only and nodev attributes which userspace happens to keep
  consistent are enforced.  Dealing with the noexec and nosuid
  attributes remains for another time.

  This set of changes also addresses an issue with how open file
  descriptors from /proc/<pid>/ns/* are displayed.  Recently readlink of
  /proc/<pid>/fd has been triggering a WARN_ON that has not been
  meaningful since it was added (as all of the code in the kernel was
  converted) and is not now actively wrong.

  There is also a short list of issues that have not been fixed yet that
  I will mention briefly.

  It is possible to rename a directory from below to above a bind mount.
  At which point any directory pointers below the renamed directory can
  be walked up to the root directory of the filesystem.  With user
  namespaces enabled a bind mount of the bind mount can be created
  allowing the user to pick a directory whose children they can rename
  to outside of the bind mount.  This is challenging to fix and doubly
  so because all obvious solutions must touch code that is in the
  performance part of pathname resolution.

  As mentioned above there is also a question of how to ensure that
  developers by accident or with purpose do not introduce exectuable
  files on sysfs and proc and in doing so introduce security regressions
  in the current userspace that will not be immediately obvious and as
  such are likely to require breaking userspace in painful ways once
  they are recognized"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  vfs: Remove incorrect debugging WARN in prepend_path
  mnt: Update fs_fully_visible to test for permanently empty directories
  sysfs: Create mountpoints with sysfs_create_mount_point
  sysfs: Add support for permanently empty directories to serve as mount points.
  kernfs: Add support for always empty directories.
  proc: Allow creating permanently empty directories that serve as mount points
  sysctl: Allow creating permanently empty directories that serve as mountpoints.
  fs: Add helper functions for permanently empty directories.
  vfs: Ignore unlocked mounts in fs_fully_visible
  mnt: Modify fs_fully_visible to deal with locked ro nodev and atime
  mnt: Refactor the logic for mounting sysfs and proc in a user namespace
2015-07-03 15:20:57 -07:00
Linus Torvalds
02201e3f1b Minor merge needed, due to function move.
Main excitement here is Peter Zijlstra's lockless rbtree optimization to
 speed module address lookup.  He found some abusers of the module lock
 doing that too.
 
 A little bit of parameter work here too; including Dan Streetman's breaking
 up the big param mutex so writing a parameter can load another module (yeah,
 really).  Unfortunately that broke the usual suspects, !CONFIG_MODULES and
 !CONFIG_SYSFS, so those fixes were appended too.
 
 Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "Main excitement here is Peter Zijlstra's lockless rbtree optimization
  to speed module address lookup.  He found some abusers of the module
  lock doing that too.

  A little bit of parameter work here too; including Dan Streetman's
  breaking up the big param mutex so writing a parameter can load
  another module (yeah, really).  Unfortunately that broke the usual
  suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were
  appended too"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits)
  modules: only use mod->param_lock if CONFIG_MODULES
  param: fix module param locks when !CONFIG_SYSFS.
  rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
  module: add per-module param_lock
  module: make perm const
  params: suppress unused variable error, warn once just in case code changes.
  modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
  kernel/module.c: avoid ifdefs for sig_enforce declaration
  kernel/workqueue.c: remove ifdefs over wq_power_efficient
  kernel/params.c: export param_ops_bool_enable_only
  kernel/params.c: generalize bool_enable_only
  kernel/module.c: use generic module param operaters for sig_enforce
  kernel/params: constify struct kernel_param_ops uses
  sysfs: tightened sysfs permission checks
  module: Rework module_addr_{min,max}
  module: Use __module_address() for module_address_lookup()
  module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
  module: Optimize __module_address() using a latched RB-tree
  rbtree: Implement generic latch_tree
  seqlock: Introduce raw_read_seqcount_latch()
  ...
2015-07-01 10:49:25 -07:00
Eric W. Biederman
f9bb48825a sysfs: Create mountpoints with sysfs_create_mount_point
This allows for better documentation in the code and
it allows for a simpler and fully correct version of
fs_fully_visible to be written.

The mount points converted and their filesystems are:
/sys/hypervisor/s390/       s390_hypfs
/sys/kernel/config/         configfs
/sys/kernel/debug/          debugfs
/sys/firmware/efi/efivars/  efivarfs
/sys/fs/fuse/connections/   fusectl
/sys/fs/pstore/             pstore
/sys/kernel/tracing/        tracefs
/sys/fs/cgroup/             cgroup
/sys/kernel/security/       securityfs
/sys/fs/selinux/            selinuxfs
/sys/fs/smackfs/            smackfs

Cc: stable@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:47 -05:00
Linus Torvalds
4a10a91756 Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
Pull audit updates from Paul Moore:
 "Four small audit patches for v4.2, all bug fixes.  Only 10 lines of
  change this time so very unremarkable, the patch subject lines pretty
  much tell the whole story"

* 'upstream' of git://git.infradead.org/users/pcmoore/audit:
  audit: Fix check of return value of strnlen_user()
  audit: obsolete audit_context check is removed in audit_filter_rules()
  audit: fix for typo in comment to function audit_log_link_denied()
  lsm: rename duplicate labels in LSM_AUDIT_DATA_TASK audit message type
2015-06-27 13:53:16 -07:00
Linus Torvalds
e22619a29f Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "The main change in this kernel is Casey's generalized LSM stacking
  work, which removes the hard-coding of Capabilities and Yama stacking,
  allowing multiple arbitrary "small" LSMs to be stacked with a default
  monolithic module (e.g.  SELinux, Smack, AppArmor).

  See
        https://lwn.net/Articles/636056/

  This will allow smaller, simpler LSMs to be incorporated into the
  mainline kernel and arbitrarily stacked by users.  Also, this is a
  useful cleanup of the LSM code in its own right"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (38 commits)
  tpm, tpm_crb: fix le64_to_cpu conversions in crb_acpi_add()
  vTPM: set virtual device before passing to ibmvtpm_reset_crq
  tpm_ibmvtpm: remove unneccessary message level.
  ima: update builtin policies
  ima: extend "mask" policy matching support
  ima: add support for new "euid" policy condition
  ima: fix ima_show_template_data_ascii()
  Smack: freeing an error pointer in smk_write_revoke_subj()
  selinux: fix setting of security labels on NFS
  selinux: Remove unused permission definitions
  selinux: enable genfscon labeling for sysfs and pstore files
  selinux: enable per-file labeling for debugfs files.
  selinux: update netlink socket classes
  signals: don't abuse __flush_signals() in selinux_bprm_committed_creds()
  selinux: Print 'sclass' as string when unrecognized netlink message occurs
  Smack: allow multiple labels in onlycap
  Smack: fix seq operations in smackfs
  ima: pass iint to ima_add_violation()
  ima: wrap event related data to the new ima_event_data structure
  integrity: add validity checks for 'path' parameter
  ...
2015-06-27 13:26:03 -07:00
Linus Torvalds
e0456717e4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Add TX fast path in mac80211, from Johannes Berg.

 2) Add TSO/GRO support to ibmveth, from Thomas Falcon

 3) Move away from cached routes in ipv6, just like ipv4, from Martin
    KaFai Lau.

 4) Lots of new rhashtable tests, from Thomas Graf.

 5) Run ingress qdisc lockless, from Alexei Starovoitov.

 6) Allow servers to fetch TCP packet headers for SYN packets of new
    connections, for fingerprinting.  From Eric Dumazet.

 7) Add mode parameter to pktgen, for testing receive.  From Alexei
    Starovoitov.

 8) Cache access optimizations via simplifications of build_skb(), from
    Alexander Duyck.

 9) Move page frag allocator under mm/, also from Alexander.

10) Add xmit_more support to hv_netvsc, from KY Srinivasan.

11) Add a counter guard in case we try to perform endless reclassify
    loops in the packet scheduler.

12) Extern flow dissector to be programmable and use it in new "Flower"
    classifier.  From Jiri Pirko.

13) AF_PACKET fanout rollover fixes, performance improvements, and new
    statistics.  From Willem de Bruijn.

14) Add netdev driver for GENEVE tunnels, from John W Linville.

15) Add ingress netfilter hooks and filtering, from Pablo Neira Ayuso.

16) Fix handling of epoll edge triggers in TCP, from Eric Dumazet.

17) Add an ECN retry fallback for the initial TCP handshake, from Daniel
    Borkmann.

18) Add tail call support to BPF, from Alexei Starovoitov.

19) Add several pktgen helper scripts, from Jesper Dangaard Brouer.

20) Add zerocopy support to AF_UNIX, from Hannes Frederic Sowa.

21) Favor even port numbers for allocation to connect() requests, and
    odd port numbers for bind(0), in an effort to help avoid
    ip_local_port_range exhaustion.  From Eric Dumazet.

22) Add Cavium ThunderX driver, from Sunil Goutham.

23) Allow bpf programs to access skb_iif and dev->ifindex SKB metadata,
    from Alexei Starovoitov.

24) Add support for T6 chips in cxgb4vf driver, from Hariprasad Shenai.

25) Double TCP Small Queues default to 256K to accomodate situations
    like the XEN driver and wireless aggregation.  From Wei Liu.

26) Add more entropy inputs to flow dissector, from Tom Herbert.

27) Add CDG congestion control algorithm to TCP, from Kenneth Klette
    Jonassen.

28) Convert ipset over to RCU locking, from Jozsef Kadlecsik.

29) Track and act upon link status of ipv4 route nexthops, from Andy
    Gospodarek.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1670 commits)
  bridge: vlan: flush the dynamically learned entries on port vlan delete
  bridge: multicast: add a comment to br_port_state_selection about blocking state
  net: inet_diag: export IPV6_V6ONLY sockopt
  stmmac: troubleshoot unexpected bits in des0 & des1
  net: ipv4 sysctl option to ignore routes when nexthop link is down
  net: track link-status of ipv4 nexthops
  net: switchdev: ignore unsupported bridge flags
  net: Cavium: Fix MAC address setting in shutdown state
  drivers: net: xgene: fix for ACPI support without ACPI
  ip: report the original address of ICMP messages
  net/mlx5e: Prefetch skb data on RX
  net/mlx5e: Pop cq outside mlx5e_get_cqe
  net/mlx5e: Remove mlx5e_cq.sqrq back-pointer
  net/mlx5e: Remove extra spaces
  net/mlx5e: Avoid TX CQE generation if more xmit packets expected
  net/mlx5e: Avoid redundant dev_kfree_skb() upon NOP completion
  net/mlx5e: Remove re-assignment of wq type in mlx5e_enable_rq()
  net/mlx5e: Use skb_shinfo(skb)->gso_segs rather than counting them
  net/mlx5e: Static mapping of netdev priv resources to/from netdev TX queues
  net/mlx4_en: Use HW counters for rx/tx bytes/packets in PF device
  ...
2015-06-24 16:49:49 -07:00
Al Viro
dc3f4198ea make simple_positive() public
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:02:01 -04:00
Eric W Biederman
8f481b50ea netfilter: Remove spurios included of netfilter.h
While testing my netfilter changes I noticed several files where
recompiling unncessarily because they unncessarily included
netfilter.h.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-06-18 21:14:32 +02:00
Mimi Zohar
24fd03c876 ima: update builtin policies
This patch defines a builtin measurement policy "tcb", similar to the
existing "ima_tcb", but with additional rules to also measure files
based on the effective uid and to measure files opened with the "read"
mode bit set (eg. read, read-write).

Changing the builtin "ima_tcb" policy could potentially break existing
users.  Instead of defining a new separate boot command line option each
time the builtin measurement policy is modified, this patch defines a
single generic boot command line option "ima_policy=" to specify the
builtin policy and deprecates the use of the builtin ima_tcb policy.

[The "ima_policy=" boot command line option is based on Roberto Sassu's
"ima: added new policy type exec" patch.]

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dr. Greg Wettstein <gw@idfusion.org>
Cc: stable@vger.kernel.org
2015-06-16 08:18:45 -04:00
Mimi Zohar
4351c294b8 ima: extend "mask" policy matching support
The current "mask" policy option matches files opened as MAY_READ,
MAY_WRITE, MAY_APPEND or MAY_EXEC.  This patch extends the "mask"
option to match files opened containing one of these modes.  For
example, "mask=^MAY_READ" would match files opened read-write.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dr. Greg Wettstein <gw@idfusion.org>
Cc: stable@vger.kernel.org
2015-06-16 08:18:44 -04:00
Mimi Zohar
139069eff7 ima: add support for new "euid" policy condition
The new "euid" policy condition measures files with the specified
effective uid (euid).  In addition, for CAP_SETUID files it measures
files with the specified uid or suid.

Changelog:
- fixed checkpatch.pl warnings
- fixed avc denied {setuid} messages - based on Roberto's feedback

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dr. Greg Wettstein <gw@idfusion.org>
Cc: stable@vger.kernel.org
2015-06-16 08:18:43 -04:00
Mimi Zohar
45b26133b9 ima: fix ima_show_template_data_ascii()
This patch fixes a bug introduced in "4d7aeee ima: define new template
ima-ng and template fields d-ng and n-ng".

Changelog:
- change int to uint32 (Roberto Sassu's suggestion)

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Roberto Sassu <rsassu@suse.de>
Cc: stable@vger.kernel.org # 3.13
2015-06-16 08:18:21 -04:00
James Morris
d6f7aa27f4 Merge branch 'smack-for-4.2-stacked' of https://github.com/cschaufler/smack-next into next 2015-06-13 09:51:16 +10:00
Dan Carpenter
5430209497 Smack: freeing an error pointer in smk_write_revoke_subj()
This code used to rely on the fact that kfree(NULL) was a no-op, but
then we changed smk_parse_smack() to return error pointers on failure
instead of NULL.  Calling kfree() on an error pointer will oops.

I have re-arranged things a bit so that we only free things if they
have been allocated.

Fixes: e774ad683f ('smack: pass error code through pointers')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
2015-06-12 11:59:11 -07:00
J. Bruce Fields
9fc2b4b436 selinux: fix setting of security labels on NFS
Before calling into the filesystem, vfs_setxattr calls
security_inode_setxattr, which ends up calling selinux_inode_setxattr in
our case.  That returns -EOPNOTSUPP whenever SBLABEL_MNT is not set.
SBLABEL_MNT was supposed to be set by sb_finish_set_opts, which sets it
only if selinux_is_sblabel_mnt returns true.

The selinux_is_sblabel_mnt logic was broken by eadcabc697 "SELinux: do
all flags twiddling in one place", which didn't take into the account
the SECURITY_FS_USE_NATIVE behavior that had been introduced for nfs
with eb9ae68650 "SELinux: Add new labeling type native labels".

This caused setxattr's of security labels over NFSv4.2 to fail.

Cc: stable@kernel.org # 3.13
Cc: Eric Paris <eparis@redhat.com>
Cc: David Quigley <dpquigl@davequigley.com>
Reported-by: Richard Chan <rc556677@outlook.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: added the stable dependency]
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-06-05 14:21:48 -04:00
Stephen Smalley
42a9699a9f selinux: Remove unused permission definitions
Remove unused permission definitions from SELinux.
Many of these were only ever used in pre-mainline
versions of SELinux, prior to Linux 2.6.0.  Some of them
were used in the legacy network or compat_net=1 checks
that were disabled by default in Linux 2.6.18 and
fully removed in Linux 2.6.30.

Permissions never used in mainline Linux:
file swapon
filesystem transition
tcp_socket { connectto newconn acceptfrom }
node enforce_dest
unix_stream_socket { newconn acceptfrom }

Legacy network checks, removed in 2.6.30:
socket { recv_msg send_msg }
node { tcp_recv tcp_send udp_recv udp_send rawip_recv rawip_send dccp_recv dccp_send }
netif { tcp_recv tcp_send udp_recv udp_send rawip_recv rawip_send dccp_recv dccp_send }

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-06-04 16:22:17 -04:00
Stephen Smalley
8e01472078 selinux: enable genfscon labeling for sysfs and pstore files
Support per-file labeling of sysfs and pstore files based on
genfscon policy entries.  This is safe because the sysfs
and pstore directory tree cannot be manipulated by userspace,
except to unlink pstore entries.
This provides an alternative method of assigning per-file labeling
to sysfs or pstore files without needing to set the labels from
userspace on each boot.  The advantages of this approach are that
the labels are assigned as soon as the dentry is first instantiated
and userspace does not need to walk the sysfs or pstore tree and
set the labels on each boot.  The limitations of this approach are
that the labels can only be assigned based on pathname prefix matching.
You can initially assign labels using this mechanism and then change
them at runtime via setxattr if allowed to do so by policy.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Suggested-by: Dominick Grift <dac.override@gmail.com>
Acked-by: Jeff Vander Stoep <jeffv@google.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-06-04 16:22:17 -04:00
Stephen Smalley
134509d54e selinux: enable per-file labeling for debugfs files.
Add support for per-file labeling of debugfs files so that
we can distinguish them in policy.  This is particularly
important in Android where certain debugfs files have to be writable
by apps and therefore the debugfs directory tree can be read and
searched by all.

Since debugfs is entirely kernel-generated, the directory tree is
immutable by userspace, and the inodes are pinned in memory, we can
simply use the same approach as with proc and label the inodes from
policy based on pathname from the root of the debugfs filesystem.
Generalize the existing labeling support used for proc and reuse it
for debugfs too.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-06-04 16:22:17 -04:00
Stephen Smalley
6c6d2e9bde selinux: update netlink socket classes
Update the set of SELinux netlink socket class definitions to match
the set of netlink protocols implemented by the kernel.  The
ip_queue implementation for the NETLINK_FIREWALL and NETLINK_IP6_FW protocols
was removed in d16cf20e2f, so we can remove
the corresponding class definitions as this is dead code.  Add new
classes for NETLINK_ISCSI, NETLINK_FIB_LOOKUP, NETLINK_CONNECTOR,
NETLINK_NETFILTER, NETLINK_GENERIC, NETLINK_SCSITRANSPORT, NETLINK_RDMA,
and NETLINK_CRYPTO so that we can distinguish among sockets created
for each of these protocols.  This change does not define the finer-grained
nlsmsg_read/write permissions or map specific nlmsg_type values to those
permissions in the SELinux nlmsgtab; if finer-grained control of these
sockets is desired/required, that can be added as a follow-on change.
We do not define a SELinux class for NETLINK_ECRYPTFS as the implementation
was removed in 624ae52845.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-06-04 16:22:16 -04:00
Oleg Nesterov
9e7c8f8c62 signals: don't abuse __flush_signals() in selinux_bprm_committed_creds()
selinux_bprm_committed_creds()->__flush_signals() is not right, we
shouldn't clear TIF_SIGPENDING unconditionally. There can be other
reasons for signal_pending(): freezing(), JOBCTL_PENDING_MASK, and
potentially more.

Also change this code to check fatal_signal_pending() rather than
SIGNAL_GROUP_EXIT, it looks a bit better.

Now we can kill __flush_signals() before it finds another buggy user.

Note: this code looks racy, we can flush a signal which was sent after
the task SID has been updated.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-06-04 16:22:16 -04:00