Commit Graph

1809 Commits

Author SHA1 Message Date
Eric W. Biederman
ae2975bc34 userns: Convert group_info values from gid_t to kgid_t.
As a first step to converting struct cred to be all kuid_t and kgid_t
values convert the group values stored in group_info to always be
kgid_t values.   Unless user namespaces are used this change should
have no effect.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-05-03 03:27:21 -07:00
Eric W. Biederman
783291e690 userns: Simplify the user_namespace by making userns->creator a kuid.
- Transform userns->creator from a user_struct reference to a simple
  kuid_t, kgid_t pair.

  In cap_capable this allows the check to see if we are the creator of
  a namespace to become the classic suser style euid permission check.

  This allows us to remove the need for a struct cred in the mapping
  functions and still be able to dispaly the user namespace creators
  uid and gid as 0.

- Remove the now unnecessary delayed_work in free_user_ns.

  All that is left for free_user_ns to do is to call kmem_cache_free
  and put_user_ns.  Those functions can be called in any context
  so call them directly from free_user_ns removing the need for delayed work.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-04-26 02:00:59 -07:00
Dan Carpenter
08162e6a23 Yama: remove an unused variable
GCC complains that we don't use "one" any more after 389da25f93 "Yama:
add additional ptrace scopes".

security/yama/yama_lsm.c:322:12: warning: ?one? defined but not used
	[-Wunused-variable]

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-04-23 17:20:22 +10:00
Kees Cook
389da25f93 Yama: add additional ptrace scopes
This expands the available Yama ptrace restrictions to include two more
modes. Mode 2 requires CAP_SYS_PTRACE for PTRACE_ATTACH, and mode 3
completely disables PTRACE_ATTACH (and locks the sysctl).

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-04-19 13:39:56 +10:00
Jonghwan Choi
51b79bee62 security: fix compile error in commoncap.c
Add missing "personality.h"
security/commoncap.c: In function 'cap_bprm_set_creds':
security/commoncap.c:510: error: 'PER_CLEAR_ON_SETID' undeclared (first use in this function)
security/commoncap.c:510: error: (Each undeclared identifier is reported only once
security/commoncap.c:510: error: for each function it appears in.)

Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-04-19 12:56:39 +10:00
Eric Paris
d52fc5dde1 fcaps: clear the same personality flags as suid when fcaps are used
If a process increases permissions using fcaps all of the dangerous
personality flags which are cleared for suid apps should also be cleared.
Thus programs given priviledge with fcaps will continue to have address space
randomization enabled even if the parent tried to disable it to make it
easier to attack.

Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-04-18 12:37:56 +10:00
Casey Schaufler
86812bb0de Smack: move label list initialization
A kernel with Smack enabled will fail if tmpfs has xattr support.

Move the initialization of predefined Smack label
list entries to the LSM initialization from the
smackfs setup. This became an issue when tmpfs
acquired xattr support, but was never correct.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-04-18 12:02:28 +10:00
John Johansen
c29bceb396 Fix execve behavior apparmor for PR_{GET,SET}_NO_NEW_PRIVS
Add support for AppArmor to explicitly fail requested domain transitions
if NO_NEW_PRIVS is set and the task is not unconfined.

Transitions from unconfined are still allowed because this always results
in a reduction of privileges.

Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Will Drewry <wad@chromium.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>

v18: new acked-by, new description
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-04-14 11:13:18 +10:00
Andy Lutomirski
259e5e6c75 Add PR_{GET,SET}_NO_NEW_PRIVS to prevent execve from granting privs
With this change, calling
  prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)
disables privilege granting operations at execve-time.  For example, a
process will not be able to execute a setuid binary to change their uid
or gid if this bit is set.  The same is true for file capabilities.

Additionally, LSM_UNSAFE_NO_NEW_PRIVS is defined to ensure that
LSMs respect the requested behavior.

To determine if the NO_NEW_PRIVS bit is set, a task may call
  prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
It returns 1 if set and 0 if it is not set. If any of the arguments are
non-zero, it will return -1 and set errno to -EINVAL.
(PR_SET_NO_NEW_PRIVS behaves similarly.)

This functionality is desired for the proposed seccomp filter patch
series.  By using PR_SET_NO_NEW_PRIVS, it allows a task to modify the
system call behavior for itself and its child tasks without being
able to impact the behavior of a more privileged task.

Another potential use is making certain privileged operations
unprivileged.  For example, chroot may be considered "safe" if it cannot
affect privileged tasks.

Note, this patch causes execve to fail when PR_SET_NO_NEW_PRIVS is
set and AppArmor is in use.  It is fixed in a subsequent patch.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Will Drewry <wad@chromium.org>
Acked-by: Eric Paris <eparis@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>

v18: updated change desc
v17: using new define values as per 3.4
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-04-14 11:13:18 +10:00
Kees Cook
923e9a1399 Smack: build when CONFIG_AUDIT not defined
This fixes builds where CONFIG_AUDIT is not defined and
CONFIG_SECURITY_SMACK=y.

This got introduced by the stack-usage reducation commit 48c62af68a
("LSM: shrink the common_audit_data data union").

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-10 16:14:40 -07:00
Eric Paris
c737f8284c SELinux: remove unused common_audit_data in flush_unauthorized_files
We don't need this variable and it just eats stack space.  Remove it.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:57 -04:00
Wanlong Gao
562c99f20d SELinux: avc: remove the useless fields in avc_add_callback
avc_add_callback now just used for registering reset functions
in initcalls, and the callback functions just did reset operations.
So, reducing the arguments to only one event is enough now.

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:44 -04:00
Wanlong Gao
0b36e44cc6 SELinux: replace weak GFP_ATOMIC to GFP_KERNEL in avc_add_callback
avc_add_callback now only called from initcalls, so replace the
weak GFP_ATOMIC to GFP_KERNEL, and mark this function __init
to make a warning when not been called from initcalls.

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:07 -04:00
Eric Paris
899838b25f SELinux: unify the selinux_audit_data and selinux_late_audit_data
We no longer need the distinction.  We only need data after we decide to do an
audit.  So turn the "late" audit data into just "data" and remove what we
currently have as "data".

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:06 -04:00
Eric Paris
1d34929271 SELinux: remove auditdeny from selinux_audit_data
It's just takin' up space.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:05 -04:00
Eric Paris
50c205f5e5 LSM: do not initialize common_audit_data to 0
It isn't needed.  If you don't set the type of the data associated with
that type it is a pretty obvious programming bug.  So why waste the cycles?

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:04 -04:00
Eric Paris
07f62eb66c LSM: BUILD_BUG_ON if the common_audit_data union ever grows
We did a lot of work to shrink the common_audit_data.  Add a BUILD_BUG_ON
so future programers (let's be honest, probably me) won't do something
foolish like make it large again!

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:03 -04:00
Eric Paris
b466066f9b LSM: remove the task field from common_audit_data
There are no legitimate users.  Always use current and get back some stack
space for the common_audit_data.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:03 -04:00
Eric Paris
0972c74ecb apparmor: move task from common_audit_data to apparmor_audit_data
apparmor is the only LSM that uses the common_audit_data tsk field.
Instead of making all LSMs pay for the stack space move the aa usage into
the apparmor_audit_data.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:02 -04:00
Eric Paris
bd5e50f9c1 LSM: remove the COMMON_AUDIT_DATA_INIT type expansion
Just open code it so grep on the source code works better.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:01 -04:00
Eric Paris
d4cf970d07 SELinux: move common_audit_data to a noinline slow path function
selinux_inode_has_perm is a hot path.  Instead of declaring the
common_audit_data on the stack move it to a noinline function only used in
the rare case we need to send an audit message.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:00 -04:00
Eric Paris
602a8dd6ea SELinux: remove inode_has_perm_noadp
Both callers could better be using file_has_perm() to get better audit
results.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:00 -04:00
Eric Paris
2e33405785 SELinux: delay initialization of audit data in selinux_inode_permission
We pay a rather large overhead initializing the common_audit_data.
Since we only need this information if we actually emit an audit
message there is little need to set it up in the hot path.  This patch
splits the functionality of avc_has_perm() into avc_has_perm_noaudit(),
avc_audit_required() and slow_avc_audit().  But we take care of setting
up to audit between required() and the actual audit call.  Thus saving
measurable time in a hot path.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:22:59 -04:00
Eric Paris
154c50ca4e SELinux: if sel_make_bools errors don't leave inconsistent state
We reset the bool names and values array to NULL, but do not reset the
number of entries in these arrays to 0.  If we error out and then get back
into this function we will walk these NULL pointers based on the belief
that they are non-zero length.

Signed-off-by: Eric Paris <eparis@redhat.com>
cc: stable@kernel.org
2012-04-09 12:22:58 -04:00
Eric Paris
92ae9e82d9 SELinux: remove needless sel_div function
I'm not really sure what the idea behind the sel_div function is, but it's
useless.  Since a and b are both unsigned, it's impossible for a % b < 0.
That means that part of the function never does anything.  Thus it's just a
normal /.  Just do that instead.  I don't even understand what that operation
was supposed to mean in the signed case however....

If it was signed:
sel_div(-2, 4) == ((-2 / 4) - ((-2 % 4) < 0))
		  ((0)      - ((-2)     < 0))
		  ((0)      - (1))
		  (-1)

What actually happens:
sel_div(-2, 4) == ((18446744073709551614 / 4) - ((18446744073709551614 % 4) < 0))
		  ((4611686018427387903)      - ((2 < 0))
		  (4611686018427387903        - 0)
		  ((unsigned int)4611686018427387903)
		  (4294967295)

Neither makes a whole ton of sense to me.  So I'm getting rid of the
function entirely.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:22:57 -04:00