Commit Graph

282 Commits

Author SHA1 Message Date
Rafal Krypa
18d872f77c Smack: ignore null signal in smack_task_kill
Kill with signal number 0 is commonly used for checking PID existence.
Smack treated such cases like any other kills, although no signal is
actually delivered when sig == 0.

Checking permissions when sig == 0 didn't prevent an unprivileged caller
from learning whether PID exists or not. When it existed, kernel returned
EPERM, when it didn't - ESRCH. The only effect of policy check in such
case is noise in audit logs.

This change lets Smack silently ignore kill() invocations with sig == 0.

Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2016-06-08 13:52:31 -07:00
Al Viro
3767e255b3 switch ->setxattr() to passing dentry and inode separately
smack ->d_instantiate() uses ->setxattr(), so to be able to call it before
we'd hashed the new dentry and attached it to inode, we need ->setxattr()
instances getting the inode as an explicit argument rather than obtaining
it from dentry.

Similar change for ->getxattr() had been done in commit ce23e64.  Unlike
->getxattr() (which is used by both selinux and smack instances of
->d_instantiate()) ->setxattr() is used only by smack one and unfortunately
it got missed back then.

Reported-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Tested-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-27 20:09:16 -04:00
Al Viro
ce23e64013 ->getxattr(): pass dentry and inode as separate arguments
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-11 00:48:00 -04:00
Al Viro
fc64005c93 don't bother with ->d_inode->i_sb - it's always equal to ->d_sb
... and neither can ever be NULL

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-10 17:11:51 -04:00
José Bollo
8012495e17 smack: fix cache of access labels
Before this commit, removing the access property of
a file, aka, the extended attribute security.SMACK64
was not effictive until the cache had been cleaned.

This patch fixes that problem.

Signed-off-by: José Bollo <jobol@nonadev.net>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2016-02-16 09:56:35 -08:00
Casey Schaufler
491a0b08d3 Smack: Remove pointless hooks
Prior to the 4.2 kernel there no no harm in providing
a security module hook that does nothing, as the default
hook would get called if the module did not supply one.
With the list based infrastructure an empty hook adds
overhead. This patch removes the three Smack hooks that
don't actually do anything.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2016-02-11 09:14:35 -08:00
Jann Horn
3dfb7d8cdb security: let security modules use PTRACE_MODE_* with bitmasks
It looks like smack and yama weren't aware that the ptrace mode
can have flags ORed into it - PTRACE_MODE_NOAUDIT until now, but
only for /proc/$pid/stat, and with the PTRACE_MODE_*CREDS patch,
all modes have flags ORed into them.

Signed-off-by: Jann Horn <jann@thejh.net>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: "Serge E. Hallyn" <serge.hallyn@ubuntu.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-20 17:09:18 -08:00
Linus Torvalds
5807fcaa9b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:

 - EVM gains support for loading an x509 cert from the kernel
   (EVM_LOAD_X509), into the EVM trusted kernel keyring.

 - Smack implements 'file receive' process-based permission checking for
   sockets, rather than just depending on inode checks.

 - Misc enhancments for TPM & TPM2.

 - Cleanups and bugfixes for SELinux, Keys, and IMA.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (41 commits)
  selinux: Inode label revalidation performance fix
  KEYS: refcount bug fix
  ima: ima_write_policy() limit locking
  IMA: policy can be updated zero times
  selinux: rate-limit netlink message warnings in selinux_nlmsg_perm()
  selinux: export validatetrans decisions
  gfs2: Invalid security labels of inodes when they go invalid
  selinux: Revalidate invalid inode security labels
  security: Add hook to invalidate inode security labels
  selinux: Add accessor functions for inode->i_security
  security: Make inode argument of inode_getsecid non-const
  security: Make inode argument of inode_getsecurity non-const
  selinux: Remove unused variable in selinux_inode_init_security
  keys, trusted: seal with a TPM2 authorization policy
  keys, trusted: select hash algorithm for TPM2 chips
  keys, trusted: fix: *do not* allow duplicate key options
  tpm_ibmvtpm: properly handle interrupted packet receptions
  tpm_tis: Tighten IRQ auto-probing
  tpm_tis: Refactor the interrupt setup
  tpm_tis: Get rid of the duplicate IRQ probing code
  ...
2016-01-17 19:13:15 -08:00
Linus Torvalds
33caf82acf Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
 "All kinds of stuff.  That probably should've been 5 or 6 separate
  branches, but by the time I'd realized how large and mixed that bag
  had become it had been too close to -final to play with rebasing.

  Some fs/namei.c cleanups there, memdup_user_nul() introduction and
  switching open-coded instances, burying long-dead code, whack-a-mole
  of various kinds, several new helpers for ->llseek(), assorted
  cleanups and fixes from various people, etc.

  One piece probably deserves special mention - Neil's
  lookup_one_len_unlocked().  Similar to lookup_one_len(), but gets
  called without ->i_mutex and tries to avoid ever taking it.  That, of
  course, means that it's not useful for any directory modifications,
  but things like getting inode attributes in nfds readdirplus are fine
  with that.  I really should've asked for moratorium on lookup-related
  changes this cycle, but since I hadn't done that early enough...  I
  *am* asking for that for the coming cycle, though - I'm going to try
  and get conversion of i_mutex to rwsem with ->lookup() done under lock
  taken shared.

  There will be a patch closer to the end of the window, along the lines
  of the one Linus had posted last May - mechanical conversion of
  ->i_mutex accesses to inode_lock()/inode_unlock()/inode_trylock()/
  inode_is_locked()/inode_lock_nested().  To quote Linus back then:

    -----
    |    This is an automated patch using
    |
    |        sed 's/mutex_lock(&\(.*\)->i_mutex)/inode_lock(\1)/'
    |        sed 's/mutex_unlock(&\(.*\)->i_mutex)/inode_unlock(\1)/'
    |        sed 's/mutex_lock_nested(&\(.*\)->i_mutex,[     ]*I_MUTEX_\([A-Z0-9_]*\))/inode_lock_nested(\1, I_MUTEX_\2)/'
    |        sed 's/mutex_is_locked(&\(.*\)->i_mutex)/inode_is_locked(\1)/'
    |        sed 's/mutex_trylock(&\(.*\)->i_mutex)/inode_trylock(\1)/'
    |
    |    with a very few manual fixups
    -----

  I'm going to send that once the ->i_mutex-affecting stuff in -next
  gets mostly merged (or when Linus says he's about to stop taking
  merges)"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  nfsd: don't hold i_mutex over userspace upcalls
  fs:affs:Replace time_t with time64_t
  fs/9p: use fscache mutex rather than spinlock
  proc: add a reschedule point in proc_readfd_common()
  logfs: constify logfs_block_ops structures
  fcntl: allow to set O_DIRECT flag on pipe
  fs: __generic_file_splice_read retry lookup on AOP_TRUNCATED_PAGE
  fs: xattr: Use kvfree()
  [s390] page_to_phys() always returns a multiple of PAGE_SIZE
  nbd: use ->compat_ioctl()
  fs: use block_device name vsprintf helper
  lib/vsprintf: add %*pg format specifier
  fs: use gendisk->disk_name where possible
  poll: plug an unused argument to do_poll
  amdkfd: don't open-code memdup_user()
  cdrom: don't open-code memdup_user()
  rsxx: don't open-code memdup_user()
  mtip32xx: don't open-code memdup_user()
  [um] mconsole: don't open-code memdup_user_nul()
  [um] hostaudio: don't open-code memdup_user()
  ...
2016-01-12 17:11:47 -08:00
Al Viro
16e5c1fc36 convert a bunch of open-coded instances of memdup_user_nul()
A _lot_ of ->write() instances were open-coding it; some are
converted to memdup_user_nul(), a lot more remain...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-04 10:26:58 -05:00
James Morris
aa98b942cb Merge branch 'smack-for-4.5' of https://github.com/cschaufler/smack-next into next 2015-12-26 16:11:13 +11:00
Andreas Gruenbacher
d6335d77a7 security: Make inode argument of inode_getsecid non-const
Make the inode argument of the inode_getsecid hook non-const so that we
can use it to revalidate invalid security labels.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-12-24 11:09:39 -05:00
Andreas Gruenbacher
ea861dfd9e security: Make inode argument of inode_getsecurity non-const
Make the inode argument of the inode_getsecurity hook non-const so that
we can use it to revalidate invalid security labels.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-12-24 11:09:39 -05:00
Roman Kubiak
81bd0d5629 Smack: type confusion in smak sendmsg() handler
Smack security handler for sendmsg() syscall
is vulnerable to type confusion issue what
can allow to privilege escalation into root
or cause denial of service.

A malicious attacker can create socket of one
type for example AF_UNIX and pass is into
sendmsg() function ensuring that this is
AF_INET socket.

Remedy
Do not trust user supplied data.
Proposed fix below.

Signed-off-by: Roman Kubiak <r.kubiak@samsung.com>
Signed-off-by: Mateusz Fruba <m.fruba@samsung.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2015-12-17 10:21:56 -08:00
Andreas Gruenbacher
c4803c497f nfs: Move call to security_inode_listsecurity into nfs_listxattr
Add a nfs_listxattr operation.  Move the call to security_inode_listsecurity
from list operation of the "security.*" xattr handler to nfs_listxattr.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-13 19:45:47 -05:00
Casey Schaufler
79be093500 Smack: File receive for sockets
The existing file receive hook checks for access on
the file inode even for UDS. This is not right, as
the inode is not used by Smack to make access checks
for sockets. This change checks for an appropriate
access relationship between the receiving (current)
process and the socket. If the process can't write
to the socket's send label or the socket's receive
label can't write to the process fail.

This will allow the legitimate cases, where the
socket sender and socket receiver can freely communicate.
Only strangly set socket labels should cause a problem.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2015-12-09 16:10:55 -08:00
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
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
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
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
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
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
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
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
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
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
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
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
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
Rafal Krypa
c0d77c8844 Smack: allow multiple labels in onlycap
Smack onlycap allows limiting of CAP_MAC_ADMIN and CAP_MAC_OVERRIDE to
processes running with the configured label. But having single privileged
label is not enough in some real use cases. On a complex system like Tizen,
there maybe few programs that need to configure Smack policy in run-time
and running them all with a single label is not always practical.
This patch extends onlycap feature for multiple labels. They are configured
in the same smackfs "onlycap" interface, separated by spaces.

Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2015-06-02 11:53:42 -07:00
Rafal Krypa
01fa8474fb Smack: fix seq operations in smackfs
Use proper RCU functions and read locking in smackfs seq_operations.

Smack gets away with not using proper RCU functions in smackfs, because
it never removes entries from these lists. But now one list will be
needed (with interface in smackfs) that will have both elements added and
removed to it.
This change will also help any future changes implementing removal of
unneeded entries from other Smack lists.

The patch also fixes handling of pos argument in smk_seq_start and
smk_seq_next. This fixes a bug in case when smackfs is read with a small
buffer:

Kernel panic - not syncing: Kernel mode fault at addr 0xfa0000011b
CPU: 0 PID: 1292 Comm: dd Not tainted 4.1.0-rc1-00012-g98179b8 #13
Stack:
 00000003 0000000d 7ff39e48 7f69fd00
 7ff39ce0 601ae4b0 7ff39d50 600e587b
 00000010 6039f690 7f69fd40 00612003
Call Trace:
 [<601ae4b0>] load2_seq_show+0x19/0x1d
 [<600e587b>] seq_read+0x168/0x331
 [<600c5943>] __vfs_read+0x21/0x101
 [<601a595e>] ? security_file_permission+0xf8/0x105
 [<600c5ec6>] ? rw_verify_area+0x86/0xe2
 [<600c5fc3>] vfs_read+0xa1/0x14c
 [<600c68e2>] SyS_read+0x57/0xa0
 [<6001da60>] handle_syscall+0x60/0x80
 [<6003087d>] userspace+0x442/0x548
 [<6001aa77>] ? interrupt_end+0x0/0x80
 [<6001daae>] ? copy_chunk_to_user+0x0/0x2b
 [<6002cb6b>] ? save_registers+0x1f/0x39
 [<60032ef7>] ? arch_prctl+0xf5/0x170
 [<6001a92d>] fork_handler+0x85/0x87

Signed-off-by: Rafal Krypa <r.krypa@samsung.com>
2015-06-02 11:53:23 -07:00
Lukasz Pawelczyk
e774ad683f smack: pass error code through pointers
This patch makes the following functions to use ERR_PTR() and related
macros to pass the appropriate error code through returned pointers:

smk_parse_smack()
smk_import_entry()
smk_fetch()

It also makes all the other functions that use them to handle the
error cases properly. This ways correct error codes from places
where they happened can be propagated to the user space if necessary.

Doing this it fixes a bug in onlycap and unconfined files
handling. Previously their content was cleared on any error from
smk_import_entry/smk_parse_smack, be it EINVAL (as originally intended)
or ENOMEM. Right now it only reacts on EINVAL passing other codes
properly to userspace.

Comments have been updated accordingly.

Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@samsung.com>
2015-05-15 08:36:03 -07:00
Seung-Woo Kim
9777582e8d Smack: ignore private inode for smack_file_receive
The dmabuf fd can be shared between processes via unix domain
socket. The file of dmabuf fd is came from anon_inode. The inode
has no set and get xattr operations, so it can not be shared
between processes with smack. This patch fixes just to ignore
private inode including anon_inode for smack_file_receive.

Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
2015-05-15 08:35:50 -07:00
Casey Schaufler
b1d9e6b064 LSM: Switch to lists of hooks
Instead of using a vector of security operations
with explicit, special case stacking of the capability
and yama hooks use lists of hooks with capability and
yama hooks included as appropriate.

The security_operations structure is no longer required.
Instead, there is a union of the function pointers that
allows all the hooks lists to use a common mechanism for
list management while retaining typing. Each module
supplies an array describing the hooks it provides instead
of a sparsely populated security_operations structure.
The description includes the element that gets put on
the hook list, avoiding the issues surrounding individual
element allocation.

The method for registering security modules is changed to
reflect the information available. The method for removing
a module, currently only used by SELinux, has also changed.
It should be generic now, however if there are potential
race conditions based on ordering of hook removal that needs
to be addressed by the calling module.

The security hooks are called from the lists and the first
failure is returned.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-05-12 15:00:41 +10:00
Casey Schaufler
e20b043a69 LSM: Add security module hook list heads
Add a list header for each security hook. They aren't used until
later in the patch series. They are grouped together in a structure
so that there doesn't need to be an external address for each.

Macro-ize the initialization of the security_operations
for each security module in anticipation of changing out
the security_operations structure.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-05-12 15:00:36 +10:00
Casey Schaufler
3c4ed7bdf5 LSM: Split security.h
The security.h header file serves two purposes,
interfaces for users of the security modules and
interfaces for security modules. Users of the
security modules don't need to know about what's
in the security_operations structure, so pull it
out into it's own header, lsm_hooks.h

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-05-12 15:00:16 +10:00
Linus Torvalds
9ec3a646fe Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fourth vfs update from Al Viro:
 "d_inode() annotations from David Howells (sat in for-next since before
  the beginning of merge window) + four assorted fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  RCU pathwalk breakage when running into a symlink overmounting something
  fix I_DIO_WAKEUP definition
  direct-io: only inc/dec inode->i_dio_count for file systems
  fs/9p: fix readdir()
  VFS: assorted d_backing_inode() annotations
  VFS: fs/inode.c helpers: d_inode() annotations
  VFS: fs/cachefiles: d_backing_inode() annotations
  VFS: fs library helpers: d_inode() annotations
  VFS: assorted weird filesystems: d_inode() annotations
  VFS: normal filesystems (and lustre): d_inode() annotations
  VFS: security/: d_inode() annotations
  VFS: security/: d_backing_inode() annotations
  VFS: net/: d_inode() annotations
  VFS: net/unix: d_backing_inode() annotations
  VFS: kernel/: d_inode() annotations
  VFS: audit: d_backing_inode() annotations
  VFS: Fix up some ->d_inode accesses in the chelsio driver
  VFS: Cachefiles should perform fs modifications on the top layer only
  VFS: AF_UNIX sockets should call mknod on the top layer only
2015-04-26 17:22:07 -07:00
David Howells
ce0b16ddf1 VFS: security/: d_inode() annotations
... except where that code acts as a filesystem driver, rather than
working with dentries given to it.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:57 -04:00
David Howells
c6f493d631 VFS: security/: d_backing_inode() annotations
most of the ->d_inode uses there refer to the same inode IO would
go to, i.e. d_backing_inode()

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:56 -04:00
Linus Torvalds
d488d3a4ce Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "Highlights for this window:

   - improved AVC hashing for SELinux by John Brooks and Stephen Smalley

   - addition of an unconfined label to Smack

   - Smack documentation update

   - TPM driver updates"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (28 commits)
  lsm: copy comm before calling audit_log to avoid race in string printing
  tomoyo: Do not generate empty policy files
  tomoyo: Use if_changed when generating builtin-policy.h
  tomoyo: Use bin2c to generate builtin-policy.h
  selinux: increase avtab max buckets
  selinux: Use a better hash function for avtab
  selinux: convert avtab hash table to flex_array
  selinux: reconcile security_netlbl_secattr_to_sid() and mls_import_netlbl_cat()
  selinux: remove unnecessary pointer reassignment
  Smack: Updates for Smack documentation
  tpm/st33zp24/spi: Add missing device table for spi phy.
  tpm/st33zp24: Add proper wait for ordinal duration in case of irq mode
  smack: Fix gcc warning from unused smack_syslog_lock mutex in smackfs.c
  Smack: Allow an unconfined label in bringup mode
  Smack: getting the Smack security context of keys
  Smack: Assign smack_known_web as default smk_in label for kernel thread's socket
  tpm/tpm_infineon: Use struct dev_pm_ops for power management
  MAINTAINERS: Add Jason as designated reviewer for TPM
  tpm: Update KConfig text to include TPM2.0 FIFO chips
  tpm/st33zp24/dts/st33zp24-spi: Add dts documentation for st33zp24 spi phy
  ...
2015-04-15 11:08:27 -07:00
Linus Torvalds
6c373ca893 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Add BQL support to via-rhine, from Tino Reichardt.

 2) Integrate SWITCHDEV layer support into the DSA layer, so DSA drivers
    can support hw switch offloading.  From Floria Fainelli.

 3) Allow 'ip address' commands to initiate multicast group join/leave,
    from Madhu Challa.

 4) Many ipv4 FIB lookup optimizations from Alexander Duyck.

 5) Support EBPF in cls_bpf classifier and act_bpf action, from Daniel
    Borkmann.

 6) Remove the ugly compat support in ARP for ugly layers like ax25,
    rose, etc.  And use this to clean up the neigh layer, then use it to
    implement MPLS support.  All from Eric Biederman.

 7) Support L3 forwarding offloading in switches, from Scott Feldman.

 8) Collapse the LOCAL and MAIN ipv4 FIB tables when possible, to speed
    up route lookups even further.  From Alexander Duyck.

 9) Many improvements and bug fixes to the rhashtable implementation,
    from Herbert Xu and Thomas Graf.  In particular, in the case where
    an rhashtable user bulk adds a large number of items into an empty
    table, we expand the table much more sanely.

10) Don't make the tcp_metrics hash table per-namespace, from Eric
    Biederman.

11) Extend EBPF to access SKB fields, from Alexei Starovoitov.

12) Split out new connection request sockets so that they can be
    established in the main hash table.  Much less false sharing since
    hash lookups go direct to the request sockets instead of having to
    go first to the listener then to the request socks hashed
    underneath.  From Eric Dumazet.

13) Add async I/O support for crytpo AF_ALG sockets, from Tadeusz Struk.

14) Support stable privacy address generation for RFC7217 in IPV6.  From
    Hannes Frederic Sowa.

15) Hash network namespace into IP frag IDs, also from Hannes Frederic
    Sowa.

16) Convert PTP get/set methods to use 64-bit time, from Richard
    Cochran.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1816 commits)
  fm10k: Bump driver version to 0.15.2
  fm10k: corrected VF multicast update
  fm10k: mbx_update_max_size does not drop all oversized messages
  fm10k: reset head instead of calling update_max_size
  fm10k: renamed mbx_tx_dropped to mbx_tx_oversized
  fm10k: update xcast mode before synchronizing multicast addresses
  fm10k: start service timer on probe
  fm10k: fix function header comment
  fm10k: comment next_vf_mbx flow
  fm10k: don't handle mailbox events in iov_event path and always process mailbox
  fm10k: use separate workqueue for fm10k driver
  fm10k: Set PF queues to unlimited bandwidth during virtualization
  fm10k: expose tx_timeout_count as an ethtool stat
  fm10k: only increment tx_timeout_count in Tx hang path
  fm10k: remove extraneous "Reset interface" message
  fm10k: separate PF only stats so that VF does not display them
  fm10k: use hw->mac.max_queues for stats
  fm10k: only show actual queues, not the maximum in hardware
  fm10k: allow creation of VLAN on default vid
  fm10k: fix unused warnings
  ...
2015-04-15 09:00:47 -07:00
Al Viro
39c853ebfe Merge branch 'for-davem' into for-next 2015-04-11 22:27:19 -04:00
Al Viro
3f7036a071 switch security_inode_getattr() to struct path *
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:24:32 -04:00
David S. Miller
238e54c9cb netfilter: Make nf_hookfn use nf_hook_state.
Pass the nf_hook_state all the way down into the hook
functions themselves.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-04 12:31:38 -04:00