This is a purely cosmetic change that encapsulates the three-step sidtab
conversion logic (shutdown -> clone -> map) into a single function
defined in sidtab.c (as opposed to services.c).
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: whitespaces fixes to make checkpatch happy]
Signed-off-by: Paul Moore <paul@paul-moore.com>
The intended behavior change for this patch is to reject any MLS strings
that contain (trailing) garbage if p->mls_enabled is true.
As suggested by Paul Moore, change mls_context_to_sid() so that the two
parts of the range are extracted before the rest of the parsing. Because
now we don't have to scan for two different separators simultaneously
everywhere, we can actually switch to strchr() everywhere instead of the
open-coded loops that scan for two separators at once.
mls_context_to_sid() used to signal how much of the input string was parsed
by updating `*scontext`. However, there is actually no case in which
mls_context_to_sid() only parses a subset of the input and still returns
a success (other than the buggy case with a second '-' in which it
incorrectly claims to have consumed the entire string). Turn `scontext`
into a simple pointer argument and stop redundantly checking whether the
entire input was consumed in string_to_context_struct(). This also lets us
remove the `scontext_len` argument from `string_to_context_struct()`.
Signed-off-by: Jann Horn <jannh@google.com>
[PM: minor merge fuzz in convert_context()]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Replace printk with pr_* to avoid checkpatch warnings.
Signed-off-by: Peter Enderborg <peter.enderborg@sony.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
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Merge tag 'audit-pr-20180605' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit updates from Paul Moore:
"Another reasonable chunk of audit changes for v4.18, thirteen patches
in total.
The thirteen patches can mostly be broken down into one of four
categories: general bug fixes, accessor functions for audit state
stored in the task_struct, negative filter matches on executable
names, and extending the (relatively) new seccomp logging knobs to the
audit subsystem.
The main driver for the accessor functions from Richard are the
changes we're working on to associate audit events with containers,
but I think they have some standalone value too so I figured it would
be good to get them in now.
The seccomp/audit patches from Tyler apply the seccomp logging
improvements from a few releases ago to audit's seccomp logging;
starting with this patchset the changes in
/proc/sys/kernel/seccomp/actions_logged should apply to both the
standard kernel logging and audit.
As usual, everything passes the audit-testsuite and it happens to
merge cleanly with your tree"
[ Heh, except it had trivial merge conflicts with the SELinux tree that
also came in from Paul - Linus ]
* tag 'audit-pr-20180605' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: Fix wrong task in comparison of session ID
audit: use existing session info function
audit: normalize loginuid read access
audit: use new audit_context access funciton for seccomp_actions_logged
audit: use inline function to set audit context
audit: use inline function to get audit context
audit: convert sessionid unset to a macro
seccomp: Don't special case audited processes when logging
seccomp: Audit attempts to modify the actions_logged sysctl
seccomp: Configurable separator for the actions_logged string
seccomp: Separate read and write code for actions_logged sysctl
audit: allow not equal op for audit by executable
audit: add syscall information to FEATURE_CHANGE records
Call trace:
[<ffffff9203a8d7a8>] dump_backtrace+0x0/0x428
[<ffffff9203a8dbf8>] show_stack+0x28/0x38
[<ffffff920409bfb8>] dump_stack+0xd4/0x124
[<ffffff9203d187e8>] print_address_description+0x68/0x258
[<ffffff9203d18c00>] kasan_report.part.2+0x228/0x2f0
[<ffffff9203d1927c>] kasan_report+0x5c/0x70
[<ffffff9203d1776c>] check_memory_region+0x12c/0x1c0
[<ffffff9203d17cdc>] memcpy+0x34/0x68
[<ffffff9203d75348>] xattr_getsecurity+0xe0/0x160
[<ffffff9203d75490>] vfs_getxattr+0xc8/0x120
[<ffffff9203d75d68>] getxattr+0x100/0x2c8
[<ffffff9203d76fb4>] SyS_fgetxattr+0x64/0xa0
[<ffffff9203a83f70>] el0_svc_naked+0x24/0x28
If user get root access and calls security.selinux setxattr() with an
embedded NUL on a file and then if some process performs a getxattr()
on that file with a length greater than the actual length of the string,
it would result in a panic.
To fix this, add the actual length of the string to the security context
instead of the length passed by the userspace process.
Signed-off-by: Sachin Grover <sgrover@codeaurora.org>
Cc: stable@vger.kernel.org
Signed-off-by: Paul Moore <paul@paul-moore.com>
Recognizing that the audit context is an internal audit value, use an
access function to retrieve the audit context pointer for the task
rather than reaching directly into the task struct to get it.
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: merge fuzz in auditsc.c and selinuxfs.c, checkpatch.pl fixes]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Wrap the AVC state within the selinux_state structure and
pass it explicitly to all AVC functions. The AVC private state
is encapsulated in a selinux_avc structure that is referenced
from the selinux_state.
This change should have no effect on SELinux behavior or
APIs (userspace or LSM).
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: James Morris <james.morris@microsoft.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
If security_get_bools/classes are called before the selinux state is
initialized (i.e. before first policy load), then they should just
return immediately with no booleans/classes.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Define a selinux state structure (struct selinux_state) for
global SELinux state and pass it explicitly to all security server
functions. The public portion of the structure contains state
that is used throughout the SELinux code, such as the enforcing mode.
The structure also contains a pointer to a selinux_ss structure whose
definition is private to the security server and contains security
server specific state such as the policy database and SID table.
This change should have no effect on SELinux behavior or APIs
(userspace or LSM). It merely wraps SELinux state and passes it
explicitly as needed.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: minor fixups needed due to collisions with the SCTP patches]
Signed-off-by: Paul Moore <paul@paul-moore.com>
We can't do anything reasonable in security_bounded_transition() if we
don't have a policy loaded, and in fact we could run into problems
with some of the code inside expecting a policy. Fix these problems
like we do many others in security/selinux/ss/services.c by checking
to see if the policy is loaded (ss_initialized) and returning quickly
if it isn't.
Reported-by: syzbot <syzkaller-bugs@googlegroups.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: James Morris <james.l.morris@oracle.com>
The syzbot/syzkaller automated tests found a problem in
security_context_to_sid_core() during early boot (before we load the
SELinux policy) where we could potentially feed context strings without
NUL terminators into the strcmp() function.
We already guard against this during normal operation (after the SELinux
policy has been loaded) by making a copy of the context strings and
explicitly adding a NUL terminator to the end. The patch extends this
protection to the early boot case (no loaded policy) by moving the context
copy earlier in security_context_to_sid_core().
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Reviewed-By: William Roberts <william.c.roberts@intel.com>
During random test as own device to check slub account,
we found some slack memory from hashtab_node(kmalloc-64).
By using kzalloc(), middle of test result like below:
allocated size 240768
request size 45144
slack size 195624
allocation count 3762
So, we want to use kmem_cache_zalloc() and that
can reduce memory size 52byte(slack size/alloc count) per each struct.
Signed-off-by: Kyeongdon Kim <kyeongdon.kim@lge.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Update my email address since epoch.ncsc.mil no longer exists.
MAINTAINERS and CREDITS are already correct.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
As systemd ramps up enabling NNP (NoNewPrivileges) for system services,
it is increasingly breaking SELinux domain transitions for those services
and their descendants. systemd enables NNP not only for services whose
unit files explicitly specify NoNewPrivileges=yes but also for services
whose unit files specify any of the following options in combination with
running without CAP_SYS_ADMIN (e.g. specifying User= or a
CapabilityBoundingSet= without CAP_SYS_ADMIN): SystemCallFilter=,
SystemCallArchitectures=, RestrictAddressFamilies=, RestrictNamespaces=,
PrivateDevices=, ProtectKernelTunables=, ProtectKernelModules=,
MemoryDenyWriteExecute=, or RestrictRealtime= as per the systemd.exec(5)
man page.
The end result is bad for the security of both SELinux-disabled and
SELinux-enabled systems. Packagers have to turn off these
options in the unit files to preserve SELinux domain transitions. For
users who choose to disable SELinux, this means that they miss out on
at least having the systemd-supported protections. For users who keep
SELinux enabled, they may still be missing out on some protections
because it isn't necessarily guaranteed that the SELinux policy for
that service provides the same protections in all cases.
commit 7b0d0b40cd ("selinux: Permit bounded transitions under
NO_NEW_PRIVS or NOSUID.") allowed bounded transitions under NNP in
order to support limited usage for sandboxing programs. However,
defining typebounds for all of the affected service domains
is impractical to implement in policy, since typebounds requires us
to ensure that each domain is allowed everything all of its descendant
domains are allowed, and this has to be repeated for the entire chain
of domain transitions. There is no way to clone all allow rules from
descendants to their ancestors in policy currently, and doing so would
be undesirable even if it were practical, as it requires leaking
permissions to objects and operations into ancestor domains that could
weaken their own security in order to allow them to the descendants
(e.g. if a descendant requires execmem permission, then so do all of
its ancestors; if a descendant requires execute permission to a file,
then so do all of its ancestors; if a descendant requires read to a
symbolic link or temporary file, then so do all of its ancestors...).
SELinux domains are intentionally not hierarchical / bounded in this
manner normally, and making them so would undermine their protections
and least privilege.
We have long had a similar tension with SELinux transitions and nosuid
mounts, albeit not as severe. Users often have had to choose between
retaining nosuid on a mount and allowing SELinux domain transitions on
files within those mounts. This likewise leads to unfortunate tradeoffs
in security.
Decouple NNP/nosuid from SELinux transitions, so that we don't have to
make a choice between them. Introduce a nnp_nosuid_transition policy
capability that enables transitions under NNP/nosuid to be based on
a permission (nnp_transition for NNP; nosuid_transition for nosuid)
between the old and new contexts in addition to the current support
for bounded transitions. Domain transitions can then be allowed in
policy without requiring the parent to be a strict superset of all of
its children.
With this change, systemd unit files can be left unmodified from upstream.
SELinux-disabled and SELinux-enabled users will benefit from retaining any
of the systemd-provided protections. SELinux policy will only need to
be adapted to enable the new policy capability and to allow the
new permissions between domain pairs as appropriate.
NB: Allowing nnp_transition between two contexts opens up the potential
for the old context to subvert the new context by installing seccomp
filters before the execve. Allowing nosuid_transition between two contexts
opens up the potential for a context transition to occur on a file from
an untrusted filesystem (e.g. removable media or remote filesystem). Use
with care.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
The allocated size for each ebitmap_node is 192byte by kzalloc().
Then, ebitmap_node size is fixed, so it's possible to use only 144byte
for each object by kmem_cache_zalloc().
It can reduce some dynamic allocation size.
Signed-off-by: Junil Lee <junil0814.lee@lge.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Add a type for Infiniband ports and an access vector for subnet
management packets. Implement the ib_port_smp hook to check that the
caller has permission to send and receive SMPs on the end port specified
by the device name and port. Add interface to query the SID for a IB
port, which walks the IB_PORT ocontexts to find an entry for the
given name and port.
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Add a type and access vector for PKeys. Implement the ib_pkey_access
hook to check that the caller has permission to access the PKey on the
given subnet prefix. Add an interface to get the PKey SID. Walk the PKey
ocontexts to find an entry for the given subnet prefix and pkey.
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Log the state of SELinux policy capabilities when a policy is loaded.
For each policy capability known to the kernel, log the policy capability
name and the value set in the policy. For policy capabilities that are
set in the loaded policy but unknown to the kernel, log the policy
capability index, since this is the only information presently available
in the policy.
Sample output with a policy created with a new capability defined
that is not known to the kernel:
SELinux: policy capability network_peer_controls=1
SELinux: policy capability open_perms=1
SELinux: policy capability extended_socket_class=1
SELinux: policy capability always_check_network=0
SELinux: policy capability cgroup_seclabel=0
SELinux: unknown policy capability 5
Resolves: https://github.com/SELinuxProject/selinux-kernel/issues/32
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
'perms' will never be NULL since it isn't a plain pointer but an array
of u32 values.
This fixes the following warning when building with clang:
security/selinux/ss/services.c:158:16: error: address of array
'p_in->perms' will always evaluate to 'true'
[-Werror,-Wpointer-bool-conversion]
while (p_in->perms && p_in->perms[k]) {
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
commit 1ea0ce4069 ("selinux: allow
changing labels for cgroupfs") broke the Android init program,
which looks up security contexts whenever creating directories
and attempts to assign them via setfscreatecon().
When creating subdirectories in cgroup mounts, this would previously
be ignored since cgroup did not support userspace setting of security
contexts. However, after the commit, SELinux would attempt to honor
the requested context on cgroup directories and fail due to permission
denial. Avoid breaking existing userspace/policy by wrapping this change
with a conditional on a new cgroup_seclabel policy capability. This
preserves existing behavior until/unless a new policy explicitly enables
this capability.
Reported-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Extend SELinux to support distinctions among all network address families
implemented by the kernel by defining new socket security classes
and mapping to them. Otherwise, many sockets are mapped to the generic
socket class and are indistinguishable in policy. This has come up
previously with regard to selectively allowing access to bluetooth sockets,
and more recently with regard to selectively allowing access to AF_ALG
sockets. Guido Trentalancia submitted a patch that took a similar approach
to add only support for distinguishing AF_ALG sockets, but this generalizes
his approach to handle all address families implemented by the kernel.
Socket security classes are also added for ICMP and SCTP sockets.
Socket security classes were not defined for AF_* values that are reserved
but unimplemented in the kernel, e.g. AF_NETBEUI, AF_SECURITY, AF_ASH,
AF_ECONET, AF_SNA, AF_WANPIPE.
Backward compatibility is provided by only enabling the finer-grained
socket classes if a new policy capability is set in the policy; older
policies will behave as before. The legacy redhat1 policy capability
that was only ever used in testing within Fedora for ptrace_child
is reclaimed for this purpose; as far as I can tell, this policy
capability is not enabled in any supported distro policy.
Add a pair of conditional compilation guards to detect when new AF_* values
are added so that we can update SELinux accordingly rather than having to
belatedly update it long after new address families are introduced.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
The current bounds checking of both source and target types
requires allowing any domain that has access to the child
domain to also have the same permissions to the parent, which
is undesirable. Drop the target bounds checking.
KaiGai Kohei originally removed all use of target bounds in
commit 7d52a155e3 ("selinux: remove dead code in
type_attribute_bounds_av()") but this was reverted in
commit 2ae3ba3938 ("selinux: libsepol: remove dead code in
check_avtab_hierarchy_callback()") because it would have
required explicitly allowing the parent any permissions
to the child that the child is allowed to itself.
This change in contrast retains the logic for the case where both
source and target types are bounded, thereby allowing access
if the parent of the source is allowed the corresponding
permissions to the parent of the target. Further, this change
reworks the logic such that we only perform a single computation
for each case and there is no ambiguity as to how to resolve
a bounds violation.
Under the new logic, if the source type and target types are both
bounded, then the parent of the source type must be allowed the same
permissions to the parent of the target type. If only the source
type is bounded, then the parent of the source type must be allowed
the same permissions to the target type.
Examples of the new logic and comparisons with the old logic:
1. If we have:
typebounds A B;
then:
allow B self:process <permissions>;
will satisfy the bounds constraint iff:
allow A self:process <permissions>;
is also allowed in policy.
Under the old logic, the allow rule on B satisfies the
bounds constraint if any of the following three are allowed:
allow A B:process <permissions>; or
allow B A:process <permissions>; or
allow A self:process <permissions>;
However, either of the first two ultimately require the third to
satisfy the bounds constraint under the old logic, and therefore
this degenerates to the same result (but is more efficient - we only
need to perform one compute_av call).
2. If we have:
typebounds A B;
typebounds A_exec B_exec;
then:
allow B B_exec:file <permissions>;
will satisfy the bounds constraint iff:
allow A A_exec:file <permissions>;
is also allowed in policy.
This is essentially the same as #1; it is merely included as
an example of dealing with object types related to a bounded domain
in a manner that satisfies the bounds relationship. Note that
this approach is preferable to leaving B_exec unbounded and having:
allow A B_exec:file <permissions>;
in policy because that would allow B's entrypoints to be used to
enter A. Similarly for _tmp or other related types.
3. If we have:
typebounds A B;
and an unbounded type T, then:
allow B T:file <permissions>;
will satisfy the bounds constraint iff:
allow A T:file <permissions>;
is allowed in policy.
The old logic would have been identical for this example.
4. If we have:
typebounds A B;
and an unbounded domain D, then:
allow D B:unix_stream_socket <permissions>;
is not subject to any bounds constraints under the new logic
because D is not bounded. This is desirable so that we can
allow a domain to e.g. connectto a child domain without having
to allow it to do the same to its parent.
The old logic would have required:
allow D A:unix_stream_socket <permissions>;
to also be allowed in policy.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: re-wrapped description to appease checkpatch.pl]
Signed-off-by: Paul Moore <paul@paul-moore.com>
security_get_bool_value(int bool) argument "bool" conflicts with
in-kernel macros such as BUILD_BUG(). This patch changes this to
index which isn't a type.
Cc: Paul Moore <paul@paul-moore.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Eric Paris <eparis@parisplace.org>
Cc: James Morris <james.l.morris@oracle.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andrew Perepechko <anserper@ya.ru>
Cc: Jeff Vander Stoep <jeffv@google.com>
Cc: selinux@tycho.nsa.gov
Cc: Eric Paris <eparis@redhat.com>
Cc: Paul Moore <pmoore@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
[PM: wrapped description for checkpatch.pl, use "selinux:..." as subj]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Make validatetrans decisions available through selinuxfs.
"/validatetrans" is added to selinuxfs for this purpose.
This functionality is needed by file system servers
implemented in userspace or kernelspace without the VFS
layer.
Writing "$oldcontext $newcontext $tclass $taskcontext"
to /validatetrans is expected to return 0 if the transition
is allowed and -EPERM otherwise.
Signed-off-by: Andrew Perepechko <anserper@ya.ru>
CC: andrew.perepechko@seagate.com
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
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>
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>
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>
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>
Move the NetLabel secattr MLS category import logic into
mls_import_netlbl_cat() where it belongs, and use the
mls_import_netlbl_cat() function in security_netlbl_secattr_to_sid().
Reported-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Restructure to keyword=value pairs without spaces. Drop superfluous words in
text. Make invalid_context a keyword. Change result= keyword to seresult=.
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[Minor rewrite to the patch subject line]
Signed-off-by: Paul Moore <pmoore@redhat.com>
With the introduction of fair queued rwlock, recursive read_lock()
may hang the offending process if there is a write_lock() somewhere
in between.
With recursive read_lock checking enabled, the following error was
reported:
=============================================
[ INFO: possible recursive locking detected ]
3.16.0-rc1 #2 Tainted: G E
---------------------------------------------
load_policy/708 is trying to acquire lock:
(policy_rwlock){.+.+..}, at: [<ffffffff8125b32a>]
security_genfs_sid+0x3a/0x170
but task is already holding lock:
(policy_rwlock){.+.+..}, at: [<ffffffff8125b48c>]
security_fs_use+0x2c/0x110
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(policy_rwlock);
lock(policy_rwlock);
This patch fixes the occurrence of recursive read_lock() of
policy_rwlock by adding a helper function __security_genfs_sid()
which requires caller to take the lock before calling it. The
security_fs_use() was then modified to call the new helper function.
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>
security_xfrm_policy_alloc can be called in atomic context so the
allocation should be done with GFP_ATOMIC. Add an argument to let the
callers choose the appropriate way. In order to do so a gfp argument
needs to be added to the method xfrm_policy_alloc_security in struct
security_operations and to the internal function
selinux_xfrm_alloc_user. After that switch to GFP_ATOMIC in the atomic
callers and leave GFP_KERNEL as before for the rest.
The path that needed the gfp argument addition is:
security_xfrm_policy_alloc -> security_ops.xfrm_policy_alloc_security ->
all users of xfrm_policy_alloc_security (e.g. selinux_xfrm_policy_alloc) ->
selinux_xfrm_alloc_user (here the allocation used to be GFP_KERNEL only)
Now adding a gfp argument to selinux_xfrm_alloc_user requires us to also
add it to security_context_to_sid which is used inside and prior to this
patch did only GFP_KERNEL allocation. So add gfp argument to
security_context_to_sid and adjust all of its callers as well.
CC: Paul Moore <paul@paul-moore.com>
CC: Dave Jones <davej@redhat.com>
CC: Steffen Klassert <steffen.klassert@secunet.com>
CC: Fan Du <fan.du@windriver.com>
CC: David S. Miller <davem@davemloft.net>
CC: LSM list <linux-security-module@vger.kernel.org>
CC: SELinux list <selinux@tycho.nsa.gov>
Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Setting an empty security context (length=0) on a file will
lead to incorrectly dereferencing the type and other fields
of the security context structure, yielding a kernel BUG.
As a zero-length security context is never valid, just reject
all such security contexts whether coming from userspace
via setxattr or coming from the filesystem upon a getxattr
request by SELinux.
Setting a security context value (empty or otherwise) unknown to
SELinux in the first place is only possible for a root process
(CAP_MAC_ADMIN), and, if running SELinux in enforcing mode, only
if the corresponding SELinux mac_admin permission is also granted
to the domain by policy. In Fedora policies, this is only allowed for
specific domains such as livecd for setting down security contexts
that are not defined in the build host policy.
Reproducer:
su
setenforce 0
touch foo
setfattr -n security.selinux foo
Caveat:
Relabeling or removing foo after doing the above may not be possible
without booting with SELinux disabled. Any subsequent access to foo
after doing the above will also trigger the BUG.
BUG output from Matthew Thode:
[ 473.893141] ------------[ cut here ]------------
[ 473.962110] kernel BUG at security/selinux/ss/services.c:654!
[ 473.995314] invalid opcode: 0000 [#6] SMP
[ 474.027196] Modules linked in:
[ 474.058118] CPU: 0 PID: 8138 Comm: ls Tainted: G D I
3.13.0-grsec #1
[ 474.116637] Hardware name: Supermicro X8ST3/X8ST3, BIOS 2.0
07/29/10
[ 474.149768] task: ffff8805f50cd010 ti: ffff8805f50cd488 task.ti:
ffff8805f50cd488
[ 474.183707] RIP: 0010:[<ffffffff814681c7>] [<ffffffff814681c7>]
context_struct_compute_av+0xce/0x308
[ 474.219954] RSP: 0018:ffff8805c0ac3c38 EFLAGS: 00010246
[ 474.252253] RAX: 0000000000000000 RBX: ffff8805c0ac3d94 RCX:
0000000000000100
[ 474.287018] RDX: ffff8805e8aac000 RSI: 00000000ffffffff RDI:
ffff8805e8aaa000
[ 474.321199] RBP: ffff8805c0ac3cb8 R08: 0000000000000010 R09:
0000000000000006
[ 474.357446] R10: 0000000000000000 R11: ffff8805c567a000 R12:
0000000000000006
[ 474.419191] R13: ffff8805c2b74e88 R14: 00000000000001da R15:
0000000000000000
[ 474.453816] FS: 00007f2e75220800(0000) GS:ffff88061fc00000(0000)
knlGS:0000000000000000
[ 474.489254] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 474.522215] CR2: 00007f2e74716090 CR3: 00000005c085e000 CR4:
00000000000207f0
[ 474.556058] Stack:
[ 474.584325] ffff8805c0ac3c98 ffffffff811b549b ffff8805c0ac3c98
ffff8805f1190a40
[ 474.618913] ffff8805a6202f08 ffff8805c2b74e88 00068800d0464990
ffff8805e8aac860
[ 474.653955] ffff8805c0ac3cb8 000700068113833a ffff880606c75060
ffff8805c0ac3d94
[ 474.690461] Call Trace:
[ 474.723779] [<ffffffff811b549b>] ? lookup_fast+0x1cd/0x22a
[ 474.778049] [<ffffffff81468824>] security_compute_av+0xf4/0x20b
[ 474.811398] [<ffffffff8196f419>] avc_compute_av+0x2a/0x179
[ 474.843813] [<ffffffff8145727b>] avc_has_perm+0x45/0xf4
[ 474.875694] [<ffffffff81457d0e>] inode_has_perm+0x2a/0x31
[ 474.907370] [<ffffffff81457e76>] selinux_inode_getattr+0x3c/0x3e
[ 474.938726] [<ffffffff81455cf6>] security_inode_getattr+0x1b/0x22
[ 474.970036] [<ffffffff811b057d>] vfs_getattr+0x19/0x2d
[ 475.000618] [<ffffffff811b05e5>] vfs_fstatat+0x54/0x91
[ 475.030402] [<ffffffff811b063b>] vfs_lstat+0x19/0x1b
[ 475.061097] [<ffffffff811b077e>] SyS_newlstat+0x15/0x30
[ 475.094595] [<ffffffff8113c5c1>] ? __audit_syscall_entry+0xa1/0xc3
[ 475.148405] [<ffffffff8197791e>] system_call_fastpath+0x16/0x1b
[ 475.179201] Code: 00 48 85 c0 48 89 45 b8 75 02 0f 0b 48 8b 45 a0 48
8b 3d 45 d0 b6 00 8b 40 08 89 c6 ff ce e8 d1 b0 06 00 48 85 c0 49 89 c7
75 02 <0f> 0b 48 8b 45 b8 4c 8b 28 eb 1e 49 8d 7d 08 be 80 01 00 00 e8
[ 475.255884] RIP [<ffffffff814681c7>]
context_struct_compute_av+0xce/0x308
[ 475.296120] RSP <ffff8805c0ac3c38>
[ 475.328734] ---[ end trace f076482e9d754adc ]---
Reported-by: Matthew Thode <mthode@mthode.org>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Cc: stable@vger.kernel.org
Signed-off-by: Paul Moore <pmoore@redhat.com>
Pull audit update from Eric Paris:
"Again we stayed pretty well contained inside the audit system.
Venturing out was fixing a couple of function prototypes which were
inconsistent (didn't hurt anything, but we used the same value as an
int, uint, u32, and I think even a long in a couple of places).
We also made a couple of minor changes to when a couple of LSMs called
the audit system. We hoped to add aarch64 audit support this go
round, but it wasn't ready.
I'm disappearing on vacation on Thursday. I should have internet
access, but it'll be spotty. If anything goes wrong please be sure to
cc rgb@redhat.com. He'll make fixing things his top priority"
* git://git.infradead.org/users/eparis/audit: (50 commits)
audit: whitespace fix in kernel-parameters.txt
audit: fix location of __net_initdata for audit_net_ops
audit: remove pr_info for every network namespace
audit: Modify a set of system calls in audit class definitions
audit: Convert int limit uses to u32
audit: Use more current logging style
audit: Use hex_byte_pack_upper
audit: correct a type mismatch in audit_syscall_exit()
audit: reorder AUDIT_TTY_SET arguments
audit: rework AUDIT_TTY_SET to only grab spin_lock once
audit: remove needless switch in AUDIT_SET
audit: use define's for audit version
audit: documentation of audit= kernel parameter
audit: wait_for_auditd rework for readability
audit: update MAINTAINERS
audit: log task info on feature change
audit: fix incorrect set of audit_sock
audit: print error message when fail to create audit socket
audit: fix dangling keywords in audit_log_set_loginuid() output
audit: log on errors from filter user rules
...
Two of the conditions in selinux_audit_rule_match() should never happen and
the third indicates a race that should be retried. Remove the calls to
audit_log() (which call audit_log_start()) and deal with the errors in the
caller, logging only once if the condition is met. Calling audit_log_start()
in this location makes buffer allocation and locking more complicated in the
calling tree (audit_filter_user()).
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Revert "selinux: consider filesystem subtype in policies"
This reverts commit 102aefdda4.
Explanation from Eric Paris:
SELinux policy can specify if it should use a filesystem's
xattrs or not. In current policy we have a specification that
fuse should not use xattrs but fuse.glusterfs should use
xattrs. This patch has a bug in which non-glusterfs
filesystems would match the rule saying fuse.glusterfs should
use xattrs. If both fuse and the particular filesystem in
question are not written to handle xattr calls during the mount
command, they will deadlock.
I have fixed the bug to do proper matching, however I believe a
revert is still the correct solution. The reason I believe
that is because the code still does not work. The s_subtype is
not set until after the SELinux hook which attempts to match on
the ".gluster" portion of the rule. So we cannot match on the
rule in question. The code is useless.
Signed-off-by: Paul Moore <pmoore@redhat.com>
Dynamically allocate a couple of the larger stack variables in order to
reduce the stack footprint below 1024. gcc-4.8
security/selinux/ss/services.c: In function 'security_load_policy':
security/selinux/ss/services.c:1964:1: warning: the frame size of 1104 bytes is larger than 1024 bytes [-Wframe-larger-than=]
}
Also silence a couple of checkpatch warnings at the same time.
WARNING: sizeof policydb should be sizeof(policydb)
+ memcpy(oldpolicydb, &policydb, sizeof policydb);
WARNING: sizeof policydb should be sizeof(policydb)
+ memcpy(&policydb, newpolicydb, sizeof policydb);
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Not considering sub filesystem has the following limitation. Support
for SELinux in FUSE is dependent on the particular userspace
filesystem, which is identified by the subtype. For e.g, GlusterFS,
a FUSE based filesystem supports SELinux (by mounting and processing
FUSE requests in different threads, avoiding the mount time
deadlock), whereas other FUSE based filesystems (identified by a
different subtype) have the mount time deadlock.
By considering the subtype of the filesytem in the SELinux policies,
allows us to specify a filesystem subtype, in the following way:
fs_use_xattr fuse.glusterfs gen_context(system_u:object_r:fs_t,s0);
This way not all FUSE filesystems are put in the same bucket and
subjected to the limitations of the other subtypes.
Signed-off-by: Anand Avati <avati@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Currently the packet class in SELinux is not checked if there are no
SECMARK rules in the security or mangle netfilter tables. Some systems
prefer that packets are always checked, for example, to protect the system
should the netfilter rules fail to load or if the nefilter rules
were maliciously flushed.
Add the always_check_network policy capability which, when enabled, treats
SECMARK as enabled, even if there are no netfilter SECMARK rules and
treats peer labeling as enabled, even if there is no Netlabel or
labeled IPSEC configuration.
Includes definition of "redhat1" SELinux policy capability, which
exists in the SELinux userpace library, to keep ordering correct.
The SELinux userpace portion of this was merged last year, but this kernel
change fell on the floor.
Signed-off-by: Chris PeBenito <cpebenito@tresys.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Rather than passing pointers to memory locations, strings, and other
stuff just give up on the separation and give security_fs_use the
superblock. It just makes the code easier to read (even if not easier to
reuse on some other OS)
Signed-off-by: Eric Paris <eparis@redhat.com>
We only have 6 options, so char is good enough, but use a short as that
packs nicely. This shrinks the superblock_security_struct just a little
bit.
Signed-off-by: Eric Paris <eparis@redhat.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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>
It's possible that the caller passed a NULL for scontext. However if this
is a defered mapping we might still attempt to call *scontext=kstrdup().
This is bad. Instead just return the len.
Signed-off-by: Eric Paris <eparis@redhat.com>
Because Fedora shipped userspace based on my development tree we now
have policy version 27 in the wild defining only default user, role, and
range. Thus to add default_type we need a policy.28.
Signed-off-by: Eric Paris <eparis@redhat.com>
When new objects are created we have great and flexible rules to
determine the type of the new object. We aren't quite as flexible or
mature when it comes to determining the user, role, and range. This
patch adds a new ability to specify the place a new objects user, role,
and range should come from. For users and roles it can come from either
the source or the target of the operation. aka for files the user can
either come from the source (the running process and todays default) or
it can come from the target (aka the parent directory of the new file)
examples always are done with
directory context: system_u:object_r:mnt_t:s0-s0:c0.c512
process context: unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
[no rule]
unconfined_u:object_r:mnt_t:s0 test_none
[default user source]
unconfined_u:object_r:mnt_t:s0 test_user_source
[default user target]
system_u:object_r:mnt_t:s0 test_user_target
[default role source]
unconfined_u:unconfined_r:mnt_t:s0 test_role_source
[default role target]
unconfined_u:object_r:mnt_t:s0 test_role_target
[default range source low]
unconfined_u:object_r:mnt_t:s0 test_range_source_low
[default range source high]
unconfined_u:object_r:mnt_t:s0:c0.c1023 test_range_source_high
[default range source low-high]
unconfined_u:object_r:mnt_t:s0-s0:c0.c1023 test_range_source_low-high
[default range target low]
unconfined_u:object_r:mnt_t:s0 test_range_target_low
[default range target high]
unconfined_u:object_r:mnt_t:s0:c0.c512 test_range_target_high
[default range target low-high]
unconfined_u:object_r:mnt_t:s0-s0:c0.c512 test_range_target_low-high
Signed-off-by: Eric Paris <eparis@redhat.com>
My @hp.com will no longer be valid starting August 5, 2011 so an update is
necessary. My new email address is employer independent so we don't have
to worry about doing this again any time soon.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Right now security_get_user_sids() will pass in a NULL avd pointer to
avc_has_perm_noaudit(), which then forces that function to have a dummy
entry for that case and just generally test it.
Don't do it. The normal callers all pass a real avd pointer, and this
helper function is incredibly hot. So don't make avc_has_perm_noaudit()
do conditional stuff that isn't needed for the common case.
This also avoids some duplicated stack space.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To shorten the list we need to run if filename trans rules exist for the type
of the given parent directory I put them in a hashtable. Given the policy we
are expecting to use in Fedora this takes the worst case list run from about
5,000 entries to 17.
Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Right now we walk to filename trans rule list for every inode that is
created. First passes at policy using this facility creates around 5000
filename trans rules. Running a list of 5000 entries every time is a bad
idea. This patch adds a new ebitmap to policy which has a bit set for each
ttype that has at least 1 filename trans rule. Thus when an inode is
created we can quickly determine if any rules exist for this parent
directory type and can skip the list if we know there is definitely no
relevant entry.
Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
filename_compute_type() takes as arguments the numeric value of the type of
the subject and target. It does not take a context. Thus the names are
misleading. Fix the argument names.
Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
filename_compute_type used to take a qstr, but it now takes just a name.
Fix the comments to indicate it is an objname, not a qstr.
Signed-off-by: Eric Paris <eparis@redhat.com>
The len should be an size_t but is a ssize_t. Easy enough fix to silence
build warnings. We have no need for signed-ness.
Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Commit 6f5317e730 introduced a bug in the
handling of userspace object classes that is causing breakage for Xorg
when XSELinux is enabled. Fix the bug by changing map_class() to return
SECCLASS_NULL when the class cannot be mapped to a kernel object class.
Reported-by: "Justin P. Mattock" <justinmattock@gmail.com>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The attached patch allows /selinux/create takes optional 4th argument
to support TYPE_TRANSITION with name extension for userspace object
managers.
If 4th argument is not supplied, it shall perform as existing kernel.
In fact, the regression test of SE-PostgreSQL works well on the patched
kernel.
Thanks,
Signed-off-by: KaiGai Kohei <kohei.kaigai@eu.nec.com>
[manually verify fuzz was not an issue, and it wasn't: eparis]
Signed-off-by: Eric Paris <eparis@redhat.com>
Commit 6f5317e730 introduced a bug in the
handling of userspace object classes that is causing breakage for Xorg
when XSELinux is enabled. Fix the bug by changing map_class() to return
SECCLASS_NULL when the class cannot be mapped to a kernel object class.
Reported-by: "Justin P. Mattock" <justinmattock@gmail.com>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Apply role_transition rules for all kinds of classes.
Signed-off-by: Harry Ciao <qingtao.cao@windriver.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Eric Paris <eparis@redhat.com>
The socket SID would be computed on creation and no longer inherit
its creator's SID by default. Socket may have a different type but
needs to retain the creator's role and MLS attribute in order not
to break labeled networking and network access control.
The kernel value for a class would be used to determine if the class
if one of socket classes. If security_compute_sid is called from
userspace the policy value for a class would be mapped to the relevant
kernel value first.
Signed-off-by: Harry Ciao <qingtao.cao@windriver.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Currently SELinux has rules which label new objects according to 3 criteria.
The label of the process creating the object, the label of the parent
directory, and the type of object (reg, dir, char, block, etc.) This patch
adds a 4th criteria, the dentry name, thus we can distinguish between
creating a file in an etc_t directory called shadow and one called motd.
There is no file globbing, regex parsing, or anything mystical. Either the
policy exactly (strcmp) matches the dentry name of the object or it doesn't.
This patch has no changes from today if policy does not implement the new
rules.
Signed-off-by: Eric Paris <eparis@redhat.com>
The sym_val_to_name type array can be quite large as it grows linearly with
the number of types. With known policies having over 5k types these
allocations are growing large enough that they are likely to fail. Convert
those to flex_array so no allocation is larger than PAGE_SIZE
Signed-off-by: Eric Paris <eparis@redhat.com>
In rawhide type_val_to_struct will allocate 26848 bytes, an order 3
allocations. While this hasn't been seen to fail it isn't outside the
realm of possibiliy on systems with severe memory fragmentation. Convert
to flex_array so no allocation will ever be bigger than PAGE_SIZE.
Signed-off-by: Eric Paris <eparis@redhat.com>
security_netlbl_secattr_to_sid is difficult to follow, especially the
return codes. Try to make the function obvious.
Signed-off-by: Eric Paris <eparis@redhat.com>
selinuxfs.c has lots of different standards on how to handle return paths on
error. For the most part transition to
rc=errno
if (failure)
goto out;
[...]
out:
cleanup()
return rc;
Instead of doing cleanup mid function, or having multiple returns or other
options. This doesn't do that for every function, but most of the complex
functions which have cleanup routines on error.
Signed-off-by: Eric Paris <eparis@redhat.com>
/selinux/policy allows a user to copy the policy back out of the kernel.
This patch allows userspace to actually mmap that file and use it directly.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
There is interest in being able to see what the actual policy is that was
loaded into the kernel. The patch creates a new selinuxfs file
/selinux/policy which can be read by userspace. The actual policy that is
loaded into the kernel will be written back out to userspace.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
With the (long ago) interface change to have the secid_to_secctx functions
do the string allocation instead of having the caller do the allocation we
lost the ability to query the security server for the length of the
upcoming string. The SECMARK code would like to allocate a netlink skb
with enough length to hold the string but it is just too unclean to do the
string allocation twice or to do the allocation the first time and hold
onto the string and slen. This patch adds the ability to call
security_secid_to_secctx() with a NULL data pointer and it will just set
the slen pointer.
Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch provides a new /selinux/status entry which allows applications
read-only mmap(2).
This region reflects selinux_kernel_status structure in kernel space.
struct selinux_kernel_status
{
u32 length; /* length of this structure */
u32 sequence; /* sequence number of seqlock logic */
u32 enforcing; /* current setting of enforcing mode */
u32 policyload; /* times of policy reloaded */
u32 deny_unknown; /* current setting of deny_unknown */
};
When userspace object manager caches access control decisions provided
by SELinux, it needs to invalidate the cache on policy reload and setenforce
to keep consistency.
However, the applications need to check the kernel state for each accesses
on userspace avc, or launch a background worker process.
In heuristic, frequency of invalidation is much less than frequency of
making access control decision, so it is annoying to invoke a system call
to check we don't need to invalidate the userspace cache.
If we can use a background worker thread, it allows to receive invalidation
messages from the kernel. But it requires us an invasive coding toward the
base application in some cases; E.g, when we provide a feature performing
with SELinux as a plugin module, it is unwelcome manner to launch its own
worker thread from the module.
If we could map /selinux/status to process memory space, application can
know updates of selinux status; policy reload or setenforce.
A typical application checks selinux_kernel_status::sequence when it tries
to reference userspace avc. If it was changed from the last time when it
checked userspace avc, it means something was updated in the kernel space.
Then, the application can reset userspace avc or update current enforcing
mode, without any system call invocations.
This sequence number is updated according to the seqlock logic, so we need
to wait for a while if it is odd number.
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by: Eric Paris <eparis@redhat.com>
--
security/selinux/include/security.h | 21 ++++++
security/selinux/selinuxfs.c | 56 +++++++++++++++
security/selinux/ss/Makefile | 2 +-
security/selinux/ss/services.c | 3 +
security/selinux/ss/status.c | 129 +++++++++++++++++++++++++++++++++++
5 files changed, 210 insertions(+), 1 deletions(-)
Signed-off-by: James Morris <jmorris@namei.org>
Current selinux policy can have over 3000 types. The type_attr_map in
policy is an array sized by the number of types times sizeof(struct ebitmap)
(12 on x86_64). Basic math tells us the array is going to be of length
3000 x 12 = 36,000 bytes. The largest 'safe' allocation on a long running
system is 16k. Most of the time a 32k allocation will work. But on long
running systems a 64k allocation (what we need) can fail quite regularly.
In order to deal with this I am converting the type_attr_map to use
flex_arrays. Let the library code deal with breaking this into PAGE_SIZE
pieces.
-v2
rework some of the if(!obj) BUG() to be BUG_ON(!obj)
drop flex_array_put() calls and just use a _get() object directly
-v3
make apply to James' tree (drop the policydb_write changes)
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
policy load failure always return EINVAL even if the failure was for some
other reason (usually ENOMEM). This patch passes error codes back up the
stack where they will make their way to userspace. This might help in
debugging future problems with policy load.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
This patch revert the commit of 7d52a155e3
which removed a part of type_attribute_bounds_av as a dead code.
However, at that time, we didn't find out the target side boundary allows
to handle some of pseudo /proc/<pid>/* entries with its process's security
context well.
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
--
security/selinux/ss/services.c | 43 ++++++++++++++++++++++++++++++++++++---
1 files changed, 39 insertions(+), 4 deletions(-)
Signed-off-by: James Morris <jmorris@namei.org>
Fix a couple of sparse warnings for callers of
context_struct_to_string, which takes a *u32, not an *int.
These cases are harmless as the values are not used.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Allow runtime switching between different policy types (e.g. from a MLS/MCS
policy to a non-MLS/non-MCS policy or viceversa).
Signed-off-by: Guido Trentalancia <guido@trentalancia.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Always load the initial SIDs, even in the case of a policy
reload and not just at the initial policy load. This comes
particularly handy after the introduction of a recent
patch for enabling runtime switching between different
policy types, although this patch is in theory independent
from that feature.
Signed-off-by: Guido Trentalancia <guido@trentalancia.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
This patch removes dead code in type_attribute_bounds_av().
Due to the historical reason, the type boundary feature is delivered
from hierarchical types in libsepol, it has supported boundary features
both of subject type (domain; in most cases) and target type.
However, we don't have any actual use cases in bounded target types,
and it tended to make conceptual confusion.
So, this patch removes the dead code to apply boundary checks on the
target types. I makes clear the TYPEBOUNDS restricts privileges of
a certain domain bounded to any other domain.
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
--
security/selinux/ss/services.c | 43 +++------------------------------------
1 files changed, 4 insertions(+), 39 deletions(-)
Signed-off-by: James Morris <jmorris@namei.org>
If allow_unknown==deny, SELinux treats an undefined kernel security
class as an error condition rather than as a typical permission denial
and thus does not allow permissions on undefined classes even when in
permissive mode. Change the SELinux logic so that this case is handled
as a typical permission denial, subject to the usual permissive mode and
permissive domain handling.
Also drop the 'requested' argument from security_compute_av() and
helpers as it is a legacy of the original security server interface and
is unused.
Changes:
- Handle permissive domains consistently by moving up the test for a
permissive domain.
- Make security_compute_av_user() consistent with security_compute_av();
the only difference now is that security_compute_av() performs mapping
between the kernel-private class and permission indices and the policy
values. In the userspace case, this mapping is handled by libselinux.
- Moved avd_init inside the policy lock.
Based in part on a patch by Paul Moore <paul.moore@hp.com>.
Reported-by: Andrew Worsley <amworsley@gmail.com>
Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
The size argument to kcalloc should be the size of desired structure,
not the pointer to it.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@expression@
expression *x;
@@
x =
<+...
-sizeof(x)
+sizeof(*x)
...+>// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Historically we've seen cases where permissions are requested for classes
where they do not exist. In particular we have seen CIFS forget to set
i_mode to indicate it is a directory so when we later check something like
remove_name we have problems since it wasn't defined in tclass file. This
used to result in a avc which included the permission 0x2000 or something.
Currently the kernel will deny the operations (good thing) but will not
print ANY information (bad thing). First the auditdeny field is no
extended to include unknown permissions. After that is fixed the logic in
avc_dump_query to output this information isn't right since it will remove
the permission from the av and print the phrase "<NULL>". This takes us
back to the behavior before the classmap rewrite.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Ensure that we release the policy read lock on all exit paths from
security_compute_av.
Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Drop remapping of netlink classes and bypass of permission checking
based on netlink message type for policy version < 18. This removes
compatibility code introduced when the original single netlink
security class used for all netlink sockets was split into
finer-grained netlink classes based on netlink protocol and when
permission checking was added based on netlink message type in Linux
2.6.8. The only known distribution that shipped with SELinux and
policy < 18 was Fedora Core 2, which was EOL'd on 2005-04-11.
Given that the remapping code was never updated to address the
addition of newer netlink classes, that the corresponding userland
support was dropped in 2005, and that the assumptions made by the
remapping code about the fixed ordering among netlink classes in the
policy may be violated in the future due to the dynamic class/perm
discovery support, we should drop this compatibility code now.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Modify SELinux to dynamically discover class and permission values
upon policy load, based on the dynamic object class/perm discovery
logic from libselinux. A mapping is created between kernel-private
class and permission indices used outside the security server and the
policy values used within the security server.
The mappings are only applied upon kernel-internal computations;
similar mappings for the private indices of userspace object managers
is handled on a per-object manager basis by the userspace AVC. The
interfaces for compute_av and transition_sid are split for kernel
vs. userspace; the userspace functions are distinguished by a _user
suffix.
The kernel-private class indices are no longer tied to the policy
values and thus do not need to skip indices for userspace classes;
thus the kernel class index values are compressed. The flask.h
definitions were regenerated by deleting the userspace classes from
refpolicy's definitions and then regenerating the headers. Going
forward, we can just maintain the flask.h, av_permissions.h, and
classmap.h definitions separately from policy as they are no longer
tied to the policy values. The next patch introduces a utility to
automate generation of flask.h and av_permissions.h from the
classmap.h definitions.
The older kernel class and permission string tables are removed and
replaced by a single security class mapping table that is walked at
policy load to generate the mapping. The old kernel class validation
logic is completely replaced by the mapping logic.
The handle unknown logic is reworked. reject_unknown=1 is handled
when the mappings are computed at policy load time, similar to the old
handling by the class validation logic. allow_unknown=1 is handled
when computing and mapping decisions - if the permission was not able
to be mapped (i.e. undefined, mapped to zero), then it is
automatically added to the allowed vector. If the class was not able
to be mapped (i.e. undefined, mapped to zero), then all permissions
are allowed for it if allow_unknown=1.
avc_audit leverages the new security class mapping table to lookup the
class and permission names from the kernel-private indices.
The mdp program is updated to use the new table when generating the
class definitions and allow rules for a minimal boot policy for the
kernel. It should be noted that this policy will not include any
userspace classes, nor will its policy index values for the kernel
classes correspond with the ones in refpolicy (they will instead match
the kernel-private indices).
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The attached patch adds support to generate audit messages on two cases.
The first one is a case when a multi-thread process tries to switch its
performing security context using setcon(3), but new security context is
not bounded by the old one.
type=SELINUX_ERR msg=audit(1245311998.599:17): \
op=security_bounded_transition result=denied \
oldcontext=system_u:system_r:httpd_t:s0 \
newcontext=system_u:system_r:guest_webapp_t:s0
The other one is a case when security_compute_av() masked any permissions
due to the type boundary violation.
type=SELINUX_ERR msg=audit(1245312836.035:32): \
op=security_compute_av reason=bounds \
scontext=system_u:object_r:user_webapp_t:s0 \
tcontext=system_u:object_r:shadow_t:s0:c0 \
tclass=file perms=getattr,open
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
It is a cleanup patch to cut down a line within 80 columns.
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
--
security/selinux/ss/services.c | 6 +++---
1 files changed, 3 insertions(+), 3 deletions(-)
Signed-off-by: James Morris <jmorris@namei.org>
This patch enables applications to handle permissive domain correctly.
Since the v2.6.26 kernel, SELinux has supported an idea of permissive
domain which allows certain processes to work as if permissive mode,
even if the global setting is enforcing mode.
However, we don't have an application program interface to inform
what domains are permissive one, and what domains are not.
It means applications focuses on SELinux (XACE/SELinux, SE-PostgreSQL
and so on) cannot handle permissive domain correctly.
This patch add the sixth field (flags) on the reply of the /selinux/access
interface which is used to make an access control decision from userspace.
If the first bit of the flags field is positive, it means the required
access control decision is on permissive domain, so application should
allow any required actions, as the kernel doing.
This patch also has a side benefit. The av_decision.flags is set at
context_struct_compute_av(). It enables to check required permissions
without read_lock(&policy_rwlock).
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@redhat.com>
--
security/selinux/avc.c | 2 +-
security/selinux/include/security.h | 4 +++-
security/selinux/selinuxfs.c | 4 ++--
security/selinux/ss/services.c | 30 +++++-------------------------
4 files changed, 11 insertions(+), 29 deletions(-)
Signed-off-by: James Morris <jmorris@namei.org>
It appears there was an intention to have the security server only decide
certain permissions and leave other for later as some sort of a portential
performance win. We are currently always deciding all 32 bits of
permissions and this is a useless couple of branches and wasted space.
This patch completely drops the av.decided concept.
This in a 17% reduction in the time spent in avc_has_perm_noaudit
based on oprofile sampling of a tbench benchmark.
Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Don't store the field->op in the messy (and very inconvenient for e.g.
audit_comparator()) form; translate to dense set of values and do full
validation of userland-submitted value while we are at it.
->audit_init_rule() and ->audit_match_rule() get new values now; in-tree
instances updated.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
