When a key description argument is imported into the kernel from userspace, as
happens in add_key(), request_key(), KEYCTL_JOIN_SESSION_KEYRING,
KEYCTL_SEARCH, the description is copied into a buffer up to PAGE_SIZE in size.
PAGE_SIZE, however, is a variable quantity, depending on the arch. Fix this at
4096 instead (ie. 4095 plus a NUL termination) and define a constant
(KEY_MAX_DESC_SIZE) to this end.
When reading the description back with KEYCTL_DESCRIBE, a PAGE_SIZE internal
buffer is allocated into which the information and description will be
rendered. This means that the description will get truncated if an extremely
long description it has to be crammed into the buffer with the stringified
information. There is no particular need to copy the description into the
buffer, so just copy it directly to userspace in a separate operation.
Reported-by: Christian Kastner <debian@kvr.at>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Christian Kastner <debian@kvr.at>
integrity_kernel_read() duplicates the file read operations code
in vfs_read(). This patch refactors vfs_read() code creating a
helper function __vfs_read(). It is used by both vfs_read() and
integrity_kernel_read().
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch provides CONFIG_IMA_APPRAISE_SIGNED_INIT kernel configuration
option to force IMA appraisal using signatures. This is useful, when EVM
key is not initialized yet and we want securely initialize integrity or
any other functionality.
It forces embedded policy to require signature. Signed initialization
script can initialize EVM key, update the IMA policy and change further
requirement of everything to be signed.
Changes in v3:
* kernel parameter fixed to configuration option in the patch description
Changes in v2:
* policy change of this patch separated from the key loading patch
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Keys can only be loaded once the rootfs is mounted. Initcalls
are not suitable for that. This patch defines a special hook
to load the x509 public keys onto the IMA keyring, before
attempting to access any file. The keys are required for
verifying the file's signature. The hook is called after the
root filesystem is mounted and before the kernel calls 'init'.
Changes in v3:
* added more explanation to the patch description (Mimi)
Changes in v2:
* Hook renamed as 'integrity_load_keys()' to handle both IMA and EVM
keys by integrity subsystem.
* Hook patch moved after defining loading functions
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Define configuration option to load X509 certificate into the
IMA trusted kernel keyring. It implements ima_load_x509() hook
to load X509 certificate into the .ima trusted kernel keyring
from the root filesystem.
Changes in v3:
* use ima_policy_flag in ima_get_action()
ima_load_x509 temporarily clears ima_policy_flag to disable
appraisal to load key. Use it to skip appraisal rules.
* Key directory path changed to /etc/keys (Mimi)
* Expand IMA_LOAD_X509 Kconfig help
Changes in v2:
* added '__init'
* use ima_policy_flag to disable appraisal to load keys
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Provide the function to load x509 certificates from the kernel into the
integrity kernel keyring.
Changes in v2:
* configuration option removed
* function declared as '__init'
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch defines a new function called integrity_read_file()
to read file from the kernel into a buffer. Subsequent patches
will read a file containing the public keys and load them onto
the IMA keyring.
This patch moves and renames ima_kernel_read(), the non-security
checking version of kernel_read(), to integrity_kernel_read().
Changes in v3:
* Patch descriptions improved (Mimi)
* Add missing cast (kbuild test robot)
Changes in v2:
* configuration option removed
* function declared as '__init'
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Convert WARN_ONCE() to printk() in selinux_nlmsg_perm().
After conversion from audit_log() in commit e173fb26, WARN_ONCE() was
deemed too alarmist, so switch it to printk().
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: Changed to printk(WARNING) so we catch all of the different
invalid netlink messages. In Richard's defense, he brought this
point up earlier, but I didn't understand his point at the time.]
Signed-off-by: Paul Moore <pmoore@redhat.com>
The patch use kmem_cache to allocate/free inode_smack since they are
alloced in high volumes making it a perfect case for kmem_cache.
As per analysis, 24 bytes of memory is wasted per allocation due
to internal fragmentation. With kmem_cache, this can be avoided.
Accounting of memory allocation is below :
total slack net count-alloc/free caller
Before (with kzalloc)
1919872 719952 1919872 29998/0 new_inode_smack+0x14
After (with kmem_cache)
1201680 0 1201680 30042/0 new_inode_smack+0x18
>From above data, we found that 719952 bytes(~700 KB) of memory is
saved on allocation of 29998 smack inodes.
Signed-off-by: Rohit <rohit.kr@samsung.com>
The lock access mode allows setting a read lock on a file
for with the process has only read access. The floor label is
defined to make it easy to have the basic system installed such
that everyone can read it. Once there's a desire to read lock
(rationally or otherwise) a floor file a rule needs to get set.
This happens all the time, so make the floor label a little bit
more special and allow everyone lock access, too. By implication,
give processes with the hat label (hat can read everything)
lock access as well. This reduces clutter in the Smack rule set.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
sb_finish_set_opts() can race with inode_free_security()
when initializing inode security structures for inodes
created prior to initial policy load or by the filesystem
during ->mount(). This appears to have always been
a possible race, but commit 3dc91d4 ("SELinux: Fix possible
NULL pointer dereference in selinux_inode_permission()")
made it more evident by immediately reusing the unioned
list/rcu element of the inode security structure for call_rcu()
upon an inode_free_security(). But the underlying issue
was already present before that commit as a possible use-after-free
of isec.
Shivnandan Kumar reported the list corruption and proposed
a patch to split the list and rcu elements out of the union
as separate fields of the inode_security_struct so that setting
the rcu element would not affect the list element. However,
this would merely hide the issue and not truly fix the code.
This patch instead moves up the deletion of the list entry
prior to dropping the sbsec->isec_lock initially. Then,
if the inode is dropped subsequently, there will be no further
references to the isec.
Reported-by: Shivnandan Kumar <shivnandan.k@samsung.com>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Cc: stable@vger.kernel.org
Signed-off-by: Paul Moore <pmoore@redhat.com>
Replaced the use of a Variable Length Array In Struct (VLAIS) with a C99
compliant equivalent. This patch allocates the appropriate amount of memory
using a char array using the SHASH_DESC_ON_STACK macro.
The new code can be compiled with both gcc and clang.
Signed-off-by: Behan Webster <behanw@converseincode.com>
Reviewed-by: Mark Charlebois <charlebm@gmail.com>
Reviewed-by: Jan-Simon Möller <dl9pf@gmx.de>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Cc: tglx@linutronix.de
This patch allows users to provide a custom template format through the
new kernel command line parameter 'ima_template_fmt'. If the supplied
format is not valid, IMA uses the default template descriptor.
Changelog:
- v3:
- added check for 'fields' and 'num_fields' in
template_desc_init_fields() (suggested by Mimi Zohar)
- v2:
- using template_desc_init_fields() to validate a format string
(Roberto Sassu)
- updated documentation by stating that only the chosen template
descriptor is initialized (Roberto Sassu)
- v1:
- simplified code of ima_template_fmt_setup()
(Roberto Sassu, suggested by Mimi Zohar)
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The allocation of a field pointers array is moved at the end of
template_desc_init_fields() and done only if the value of the 'fields'
and 'num_fields' parameters is not NULL. For just validating a template
format string, retrieved template field pointers are placed in a temporary
array.
Changelog:
- v3:
- do not check in this patch if 'fields' and 'num_fields' are NULL
(suggested by Mimi Zohar)
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch removes the allocation of a copy of 'template_fmt', needed for
iterating over all fields in the passed template format string. The removal
was possible by replacing strcspn(), which modifies the passed string,
with strchrnul(). The currently processed template field is copied in
a temporary variable.
The purpose of this change is use template_desc_init_fields() in two ways:
for just validating a template format string (the function should work
if called by a setup function, when memory cannot be allocated), and for
actually initializing a template descriptor. The implementation of this
feature will be complete with the next patch.
Changelog:
- v3:
- added 'goto out' in template_desc_init_fields() to free allocated
memory if a template field length is not valid (suggested by
Mimi Zohar)
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
With the introduction of the 'ima_template_fmt' kernel cmdline parameter,
a user can define a new template descriptor with custom format. However,
in this case, userspace tools will be unable to parse the measurements
list because the new template is unknown. For this reason, this patch
modifies the current IMA behavior to display in the list the template
format instead of the name (only if the length of the latter is zero)
so that a tool can extract needed information if it can handle listed
fields.
This patch also correctly displays the error log message in
ima_init_template() if the selected template cannot be initialized.
Changelog:
- v3:
- check the first byte of 'e->template_desc->name' instead of using
strlen() in ima_fs.c (suggested by Mimi Zohar)
- v2:
- print the template format in ima_init_template(), if the selected
template is custom (Roberto Sassu)
- v1:
- fixed patch description (Roberto Sassu, suggested by Mimi Zohar)
- set 'template_name' variable in ima_fs.c only once
(Roberto Sassu, suggested by Mimi Zohar)
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch adds some error messages to inform users about the following
events: template descriptor not found, invalid template descriptor,
template field not found and template initialization failed.
Changelog:
- v2:
- display an error message if the format string contains too many
fields (Roberto Sassu)
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Pull security subsystem updates from James Morris.
Mostly ima, selinux, smack and key handling updates.
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (65 commits)
integrity: do zero padding of the key id
KEYS: output last portion of fingerprint in /proc/keys
KEYS: strip 'id:' from ca_keyid
KEYS: use swapped SKID for performing partial matching
KEYS: Restore partial ID matching functionality for asymmetric keys
X.509: If available, use the raw subjKeyId to form the key description
KEYS: handle error code encoded in pointer
selinux: normalize audit log formatting
selinux: cleanup error reporting in selinux_nlmsg_perm()
KEYS: Check hex2bin()'s return when generating an asymmetric key ID
ima: detect violations for mmaped files
ima: fix race condition on ima_rdwr_violation_check and process_measurement
ima: added ima_policy_flag variable
ima: return an error code from ima_add_boot_aggregate()
ima: provide 'ima_appraise=log' kernel option
ima: move keyring initialization to ima_init()
PKCS#7: Handle PKCS#7 messages that contain no X.509 certs
PKCS#7: Better handling of unsupported crypto
KEYS: Overhaul key identification when searching for asymmetric keys
KEYS: Implement binary asymmetric key ID handling
...
The current implementation uses an atomic counter to provide exclusive
access to the sysfs 'policy' entry to update the IMA policy. While it is
highly unlikely, the usage of a counter might potentially allow another
process to overflow the counter, open the interface and insert additional
rules into the policy being loaded.
This patch replaces using an atomic counter with atomic bit operations
which is more reliable and a widely used method to provide exclusive access.
As bit operation keep the interface locked after successful update, it makes
it unnecessary to verify if the default policy was set or not during parsing
and interface closing. This patch also removes that code.
Changes in v3:
* move audit log message to ima_relead_policy() to report successful and
unsuccessful result
* unnecessary comment removed
Changes in v2:
* keep interface locked after successful policy load as in original design
* remove sysfs entry as in original design
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Empty policy lines cause parsing failures which is, especially
for new users, hard to spot. This patch prevents it.
Changes in v2:
* strip leading blanks and tabs in rules to prevent parsing failures
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
If a rule is a comment, there is no need to allocate an entry.
Move the checking for comments before allocating the entry.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Audit messages are rate limited, often causing the policy update
info to not be visible. Report policy loading status also using
pr_info.
Changes in v2:
* reporting moved to ima_release_policy to notice parsing errors
* reporting both completed and failed status
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
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Merge tag 'locks-v3.18-1' of git://git.samba.org/jlayton/linux
Pull file locking related changes from Jeff Layton:
"This release is a little more busy for file locking changes than the
last:
- a set of patches from Kinglong Mee to fix the lockowner handling in
knfsd
- a pile of cleanups to the internal file lease API. This should get
us a bit closer to allowing for setlease methods that can block.
There are some dependencies between mine and Bruce's trees this cycle,
and I based my tree on top of the requisite patches in Bruce's tree"
* tag 'locks-v3.18-1' of git://git.samba.org/jlayton/linux: (26 commits)
locks: fix fcntl_setlease/getlease return when !CONFIG_FILE_LOCKING
locks: flock_make_lock should return a struct file_lock (or PTR_ERR)
locks: set fl_owner for leases to filp instead of current->files
locks: give lm_break a return value
locks: __break_lease cleanup in preparation of allowing direct removal of leases
locks: remove i_have_this_lease check from __break_lease
locks: move freeing of leases outside of i_lock
locks: move i_lock acquisition into generic_*_lease handlers
locks: define a lm_setup handler for leases
locks: plumb a "priv" pointer into the setlease routines
nfsd: don't keep a pointer to the lease in nfs4_file
locks: clean up vfs_setlease kerneldoc comments
locks: generic_delete_lease doesn't need a file_lock at all
nfsd: fix potential lease memory leak in nfs4_setlease
locks: close potential race in lease_get_mtime
security: make security_file_set_fowner, f_setown and __f_setown void return
locks: consolidate "nolease" routines
locks: remove lock_may_read and lock_may_write
lockd: rip out deferred lock handling from testlock codepath
NFSD: Get reference of lockowner when coping file_lock
...
Cheers,
Rusty.
PS. My virtio-next tree is empty: DaveM took the patches I had. There might
be a virtio-rng starvation fix, but so far it's a bit voodoo so I will
get to that in the next two days or it will wait.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module update from Rusty Russell:
"Nothing major: support for compressing modules, and auto-tainting
params.
PS. My virtio-next tree is empty: DaveM took the patches I had. There
might be a virtio-rng starvation fix, but so far it's a bit voodoo
so I will get to that in the next two days or it will wait"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
moduleparam: Resolve missing-field-initializer warning
kbuild: handle module compression while running 'make modules_install'.
modinst: wrap long lines in order to enhance cmd_modules_install
modsign: lookup lines ending in .ko in .mod files
modpost: simplify file name generation of *.mod.c files
modpost: reduce visibility of symbols and constify r/o arrays
param: check for tainting before calling set op.
drm/i915: taint the kernel if unsafe module parameters are set
module: add module_param_unsafe and module_param_named_unsafe
module: make it possible to have unsafe, tainting module params
module: rename KERNEL_PARAM_FL_NOARG to avoid confusion
__getname() uses slab allocation which is faster than kmalloc.
Make use of it.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
If filesystem is mounted read-only or file is immutable, updating
xattr will fail. This is a usual case during early boot until
filesystem is remount read-write. This patch verifies conditions
to skip unnecessary attempt to calculate HMAC and set xattr.
Changes in v2:
* indention changed according to Lindent (requested by Mimi)
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
integrity_init_keyring() is used only from kernel '__init'
functions. Add it there as well.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch completes the switching to the 'ima_policy_flag' variable
in the checks at the beginning of IMA functions, starting with the
commit a756024e.
Checking 'iint_initialized' is completely unnecessary, because
S_IMA flag is unset if iint was not allocated. At the same time
the integrity cache is allocated with SLAB_PANIC and the kernel will
panic if the allocation fails during kernel initialization. So on
a running system iint_initialized is always true and can be removed.
Changes in v3:
* not limiting test to IMA_APPRAISE (spotted by Roberto Sassu)
Changes in v2:
* 'iint_initialized' removal patch merged to this patch (requested
by Mimi)
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Acked-by: Roberto Sassu <roberto.sassu@polito.it>
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>
Convert audit_log() call to WARN_ONCE().
Rename "type=" to nlmsg_type=" to avoid confusion with the audit record
type.
Added "protocol=" to help track down which protocol (NETLINK_AUDIT?) was used
within the netlink protocol family.
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[Rewrote the patch subject line]
Signed-off-by: Paul Moore <pmoore@redhat.com>
This patch fixes the detection of the 'open_writers' violation for mmaped
files.
before) an 'open_writers' violation is detected if the policy contains
a rule with the criteria: func=FILE_CHECK mask=MAY_READ
after) an 'open_writers' violation is detected if the current event
matches one of the policy rules.
With the old behaviour, the 'open_writers' violation is not detected
in the following case:
policy:
measure func=FILE_MMAP mask=MAY_EXEC
steps:
1) open a shared library for writing
2) execute a binary that links that shared library
3) during the binary execution, modify the shared library and save
the change
result:
the 'open_writers' violation measurement is not present in the IMA list.
Only binaries executed are protected from writes. For libraries mapped
in memory there is the flag MAP_DENYWRITE for this purpose, but according
to the output of 'man mmap', the mmap flag is ignored.
Since ima_rdwr_violation_check() is now called by process_measurement()
the information about if the inode must be measured is already provided
by ima_get_action(). Thus the unnecessary function ima_must_measure()
has been removed.
Changes in v3 (Dmitry Kasatkin):
- Violation for MMAP_CHECK function are verified since this patch
- Changed patch description a bit
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch fixes a race condition between two functions that try to access
the same inode. Since the i_mutex lock is held and released separately
in the two functions, there may be the possibility that a violation is
not correctly detected.
Suppose there are two processes, A (reader) and B (writer), if the
following sequence happens:
A: ima_rdwr_violation_check()
B: ima_rdwr_violation_check()
B: process_measurement()
B: starts writing the inode
A: process_measurement()
the ToMToU violation (a reader may be accessing a content different from
that measured, due to a concurrent modification by a writer) will not be
detected. To avoid this issue, the violation check and the measurement
must be done atomically.
This patch fixes the problem by moving the violation check inside
process_measurement() when the i_mutex lock is held. Differently from
the old code, the violation check is executed also for the MMAP_CHECK
hook (other than for FILE_CHECK). This allows to detect ToMToU violations
that are possible because shared libraries can be opened for writing
while they are in use (according to the output of 'man mmap', the mmap()
flag MAP_DENYWRITE is ignored).
Changes in v5 (Roberto Sassu):
* get iint if action is not zero
* exit process_measurement() after the violation check if action is zero
* reverse order process_measurement() exit cleanup (Mimi)
Changes in v4 (Dmitry Kasatkin):
* iint allocation is done before calling ima_rdrw_violation_check()
(Suggested-by Mimi)
* do not check for violations if the policy does not contain 'measure'
rules (done by Roberto Sassu)
Changes in v3 (Dmitry Kasatkin):
* no violation checking for MMAP_CHECK function in this patch
* remove use of filename from violation
* removes checking if ima is enabled from ima_rdrw_violation_check
* slight style change
Suggested-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch introduces the new variable 'ima_policy_flag', whose bits
are set depending on the action of the current policy rules. Only the
flags IMA_MEASURE, IMA_APPRAISE and IMA_AUDIT are set.
The new variable will be used to improve performance by skipping the
unnecessary execution of IMA code if the policy does not contain rules
with the above actions.
Changes in v6 (Roberto Sassu)
* do not check 'ima_initialized' before calling ima_update_policy_flag()
in ima_update_policy() (suggested by Dmitry)
* calling ima_update_policy_flag() moved to init_ima to co-locate with
ima_initialized (Dmitry)
* add/revise comments (Mimi)
Changes in v5 (Roberto Sassu)
* reset IMA_APPRAISE flag in 'ima_policy_flag' if 'ima_appraise' is set
to zero (reported by Dmitry)
* update 'ima_policy_flag' only if IMA initialization is successful
(suggested by Mimi and Dmitry)
* check 'ima_policy_flag' instead of 'ima_initialized'
(suggested by Mimi and Dmitry)
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch modifies ima_add_boot_aggregate() to return an error code.
This way we can determine if all the initialization procedures have
been executed successfully.
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The kernel boot parameter "ima_appraise" currently defines 'off',
'enforce' and 'fix' modes. When designing a policy and labeling
the system, access to files are either blocked in the default
'enforce' mode or automatically fixed in the 'fix' mode. It is
beneficial to be able to run the system in a logging only mode,
without fixing it, in order to properly analyze the system. This
patch adds a 'log' mode to run the system in a permissive mode and
log the appraisal results.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
ima_init() is used as a single place for all initializations.
Experimental keyring patches used the 'late_initcall' which was
co-located with the late_initcall(init_ima). When the late_initcall
for the keyring initialization was abandoned, initialization moved
to init_ima, though it would be more logical to move it to ima_init,
where the rest of the initialization is done. This patch moves the
keyring initialization to ima_init() as a preparatory step for
loading the keys which will be added to ima_init() in following
patches.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Make the key matching functions pointed to by key_match_data::cmp return bool
rather than int.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
A previous patch added a ->match_preparse() method to the key type. This is
allowed to override the function called by the iteration algorithm.
Therefore, we can just set a default that simply checks for an exact match of
the key description with the original criterion data and allow match_preparse
to override it as needed.
The key_type::match op is then redundant and can be removed, as can the
user_match() function.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Remove key_type::def_lookup_type as it's no longer used. The information now
defaults to KEYRING_SEARCH_LOOKUP_DIRECT but may be overridden by
type->match_preparse().
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Preparse the match data. This provides several advantages:
(1) The preparser can reject invalid criteria up front.
(2) The preparser can convert the criteria to binary data if necessary (the
asymmetric key type really wants to do binary comparison of the key IDs).
(3) The preparser can set the type of search to be performed. This means
that it's not then a one-off setting in the key type.
(4) The preparser can set an appropriate comparator function.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
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Merge tag 'keys-fixes-20140916' into keys-next
Merge in keyrings fixes, at least some of which later patches depend on:
(1) Reinstate the production of EPERM for key types beginning with '.' in
requests from userspace.
(2) Tidy up the cleanup of PKCS#7 message signed information blocks and fix a
bug this made more obvious.
Signed-off-by: David Howells <dhowells@redhat.coM>
Reinstate the generation of EPERM for a key type name beginning with a '.' in
a userspace call. Types whose name begins with a '.' are internal only.
The test was removed by:
commit a4e3b8d79a
Author: Mimi Zohar <zohar@linux.vnet.ibm.com>
Date: Thu May 22 14:02:23 2014 -0400
Subject: KEYS: special dot prefixed keyring name bug fix
I think we want to keep the restriction on type name so that userspace can't
add keys of a special internal type.
Note that removal of the test causes several of the tests in the keyutils
testsuite to fail.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
While SELinux largely ignores namespaces, for good reason, there are
some places where it needs to at least be aware of namespaces in order
to function correctly. Network namespaces are one example. Basic
awareness of network namespaces are necessary in order to match a
network interface's index number to an actual network device.
This patch corrects a problem with network interfaces added to a
non-init namespace, and can be reproduced with the following commands:
[NOTE: the NetLabel configuration is here only to active the dynamic
networking controls ]
# netlabelctl unlbl add default address:0.0.0.0/0 \
label:system_u:object_r:unlabeled_t:s0
# netlabelctl unlbl add default address:::/0 \
label:system_u:object_r:unlabeled_t:s0
# netlabelctl cipsov4 add pass doi:100 tags:1
# netlabelctl map add domain:lspp_test_netlabel_t \
protocol:cipsov4,100
# ip link add type veth
# ip netns add myns
# ip link set veth1 netns myns
# ip a add dev veth0 10.250.13.100/24
# ip netns exec myns ip a add dev veth1 10.250.13.101/24
# ip l set veth0 up
# ip netns exec myns ip l set veth1 up
# ping -c 1 10.250.13.101
# ip netns exec myns ping -c 1 10.250.13.100
Reported-by: Jiri Jaburek <jjaburek@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
security_file_set_fowner always returns 0, so make it f_setown and
__f_setown void return functions and fix up the error handling in the
callers.
Cc: linux-security-module@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The kernel print macros use the KBUILD_MODNAME, which is initialized
to the module name. The current integrity/Makefile makes every file
as its own module, so pr_xxx messages are prefixed with the file name
instead of the module. Similar to the evm/Makefile and ima/Makefile,
this patch fixes the integrity/Makefile to use the single name
'integrity'.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The integrity subsystem has lots of options and takes more than
half of the security menu. This patch consolidates the options
under "integrity", which are hidden if not enabled. This change
does not affect existing configurations. Re-configuration is not
needed.
Changes v4:
- no need to change "integrity subsystem" to menuconfig as
options are hidden, when not enabled. (Mimi)
- add INTEGRITY Kconfig help description
Changes v3:
- dependency to INTEGRITY removed when behind 'if INTEGRITY'
Changes v2:
- previous patch moved integrity out of the 'security' menu.
This version keeps integrity as a security option (Mimi).
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
For better visual appearance it is better to co-locate
asymmetric key options together with signature support.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
IMA uses only one template. This patch initializes only required
template to avoid unnecessary memory allocations.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Reviewed-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
In all cases except ima_bprm_check() the filename was not defined
and ima_d_path() was used to find the full path. Unfortunately,
the bprm filename is a relative pathname (eg. ./<dir>/filename).
ima_bprm_check() selects between bprm->interp and bprm->filename.
The following dump demonstrates the differences between using
filename and interp.
bprm->filename
filename: ./foo.sh, pathname: /root/bin/foo.sh
filename: ./foo.sh, pathname: /bin/dash
bprm->interp
filename: ./foo.sh, pathname: /root/bin/foo.sh
filename: /bin/sh, pathname: /bin/dash
In both cases the pathnames are currently the same. This patch
removes usage of filename and interp in favor of d_absolute_path.
Changes v3:
- 11 extra bytes for "deleted" not needed (Mimi)
- purpose "replace relative bprm filename with full pathname" (Mimi)
Changes v2:
- use d_absolute_path() instead of d_path to work in chroot environments.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
ima_get_action() sets the "action" flags based on policy.
Before collecting, measuring, appraising, or auditing the
file, the "action" flag is updated based on the cached
iint->flags.
This patch removes the subsequent unnecessary appraisal
test in ima_appraise_measurement().
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Add missing keywords to the function definition to cleanup
to discard initialization code.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Reviewed-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
'function' variable value can be changed instead of
allocating extra '_func' variable.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Precede bit testing before string comparison makes code
faster. Also refactor statement as a single line pointer
assignment. Logic is following: we set 'xattr_ptr' to read
xattr value when we will do appraisal or in any case when
measurement template is other than 'ima'.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Commit f381c27 "integrity: move ima inode integrity data management"
(re)moved few functions but left their declarations in header files.
This patch removes them and also removes duplicated declaration of
integrity_iint_find().
Commit c7de7ad "ima: remove unused cleanup functions". This patch
removes these definitions as well.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
If file has IMA signature, IMA in enforce mode, but key is missing
then file access is blocked and single error message is printed.
If IMA appraisal is enabled in fix mode, then system runs as usual
but might produce tons of 'Request for unknown key' messages.
This patch switches 'pr_warn' to 'pr_err_ratelimited'.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Empty files and missing xattrs do not guarantee that a file was
just created. This patch passes FILE_CREATED flag to IMA to
reliably identify new files.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> 3.14+
Unless an LSM labels a file during d_instantiate(), newly created
files are not labeled with an initial security.evm xattr, until
the file closes. EVM, before allowing a protected, security xattr
to be written, verifies the existing 'security.evm' value is good.
For newly created files without a security.evm label, this
verification prevents writing any protected, security xattrs,
until the file closes.
Following is the example when this happens:
fd = open("foo", O_CREAT | O_WRONLY, 0644);
setxattr("foo", "security.SMACK64", value, sizeof(value), 0);
close(fd);
While INTEGRITY_NOXATTRS status is handled in other places, such
as evm_inode_setattr(), it does not handle it in all cases in
evm_protect_xattr(). By limiting the use of INTEGRITY_NOXATTRS to
newly created files, we can now allow setting "protected" xattrs.
Changelog:
- limit the use of INTEGRITY_NOXATTRS to IMA identified new files
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> 3.14+
This patch fix spelling typo found in DocBook/kernel-api.xml.
It is because the file is generated from the source comments,
I have to fix the comments in source codes.
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Push ipv4 and ipv6 nf hooks into single array and register/unregister
them via single call.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Paul Moore <pmoore@redhat.com>
On ima_file_free(), newly created empty files are not labeled with
an initial security.ima value, because the iversion did not change.
Commit dff6efc "fs: fix iversion handling" introduced a change in
iversion behavior. To verify this change use the shell command:
$ (exec >foo)
$ getfattr -h -e hex -d -m security foo
This patch defines the IMA_NEW_FILE flag. The flag is initially
set, when IMA detects that a new file is created, and subsequently
checked on the ima_file_free() hook to set the initial security.ima
value.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> 3.14+
This patch fixes a bug, where evm_verify_hmac() returns INTEGRITY_PASS
if inode->i_op->getxattr() returns an error in evm_find_protected_xattrs.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
A previous commit c0828e5048 ("selinux:
process labeled IPsec TCP SYN-ACK packets properly in
selinux_ip_postroute()") mistakenly left out a 'break' from a switch
statement which caused problems with IPv6 traffic.
Thanks to Florian Westphal for reporting and debugging the issue.
Reported-by: Florian Westphal <fwestpha@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Now that NFS client uses the kernel key ring facility to store the NFSv4
id/gid mappings, the defaults for root_maxkeys and root_maxbytes need to be
substantially increased.
These values have been soak tested:
https://bugzilla.redhat.com/show_bug.cgi?id=1033708#c73
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
This patch fixes checkpatch 'return' warnings introduced with commit
9819cf2 "checkpatch: warn on unnecessary void function return statements".
Use scripts/checkpatch.pl --file security/integrity/evm/evm_main.c
to produce the warnings.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
3.16 commit aad4f8bb42
'switch simple generic_file_aio_read() users to ->read_iter()'
replaced ->aio_read with ->read_iter in most of the file systems
and introduced new_sync_read() as a replacement for do_sync_read().
Most of file systems set '->read' and ima_kernel_read is not affected.
When ->read is not set, this patch adopts fallback call changes from the
vfs_read.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> 3.16+
This patch fixes the case where the file's signature/hash xattr contains
an invalid hash algorithm. Although we can not verify the xattr, we still
need to measure the file. Use the default IMA hash algorithm.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The patch 3bcced39ea7d: "ima: use ahash API for file hash
calculation" from Feb 26, 2014, leads to the following static checker
warning:
security/integrity/ima/ima_crypto.c:204 ima_alloc_atfm()
error: buffer overflow 'hash_algo_name' 17 <= 17
Unlike shash tfm memory, which is allocated on initialization, the
ahash tfm memory allocation is deferred until needed.
This patch fixes the case where ima_ahash_tfm has not yet been
allocated and the file's signature/hash xattr contains an invalid hash
algorithm. Although we can not verify the xattr, we still need to
measure the file. Use the default IMA hash algorithm.
Changelog:
- set valid algo before testing tfm - based on Dmitry's comment
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Smack used to use a mix of smack_known struct and char* throughout its
APIs and implementation. This patch unifies the behaviour and makes it
store and operate exclusively on smack_known struct pointers when managing
labels.
Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@samsung.com>
Conflicts:
security/smack/smack_access.c
security/smack/smack_lsm.c
The 54e70ec5eb commit introduced a
bidirectional check that should have checked for mutual WRITE access
between two labels. Due to a typo the second check was incorrect.
Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@samsung.com>
People keep asking me for permissive mode, and I keep saying "no".
Permissive mode is wrong for more reasons than I can enumerate,
but the compelling one is that it's once on, never off.
Nonetheless, there is an argument to be made for running a
process with lots of permissions, logging which are required,
and then locking the process down. There wasn't a way to do
that with Smack, but this provides it.
The notion is that you start out by giving the process an
appropriate Smack label, such as "ATBirds". You create rules
with a wide range of access and the "b" mode. On Tizen it
might be:
ATBirds System rwxalb
ATBirds User rwxalb
ATBirds _ rwxalb
User ATBirds wb
System ATBirds wb
Accesses that fail will generate audit records. Accesses
that succeed because of rules marked with a "b" generate
log messages identifying the rule, the program and as much
object information as is convenient.
When the system is properly configured and the programs
brought in line with the labeling scheme the "b" mode can
be removed from the rules. When the system is ready for
production the facility can be configured out.
This provides the developer the convenience of permissive
mode without creating a system that looks like it is
enforcing a policy while it is not.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
If the callee SID is bounded by the caller SID, then allowing
the transition to occur poses no risk of privilege escalation and we can
therefore safely allow the transition to occur. Add this exemption
for both the case where a transition was explicitly requested by the
application and the case where an automatic transition is defined in
policy.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Make it clear this is about kernel_param_ops, not kernel_param (which
will soon have a flags field of its own). No functional changes.
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Jon Mason <jon.mason@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Commit 7177a9c4b5 ("fs: call rename2 if exists") changed
"struct inode_operations"->rename == NULL if
"struct inode_operations"->rename2 != NULL .
TOMOYO needs to check for both ->rename and ->rename2 , or
a system on (e.g.) ext4 filesystem won't boot.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
While opening with CAP_MAC_OVERRIDE file label is not set.
Other calls may access it after CAP_MAC_OVERRIDE is dropped from process.
Signed-off-by: Marcin Niesluchowski <m.niesluchow@samsung.com>
Pull SElinux fixes from Paul Moore:
"Two small patches to fix a couple of build warnings in SELinux and
NetLabel. The patches are obvious enough that I don't think any
additional explanation is necessary, but it basically boils down to
the usual: I was stupid, and these patches fix some of the stupid.
Both patches were posted earlier this week to the SELinux list, and
that is where they sat as I didn't think there were noteworthy enough
to go upstream at this point in time, but DaveM would rather see them
upstream now so who am I to argue. As the patches are both very
small"
* 'stable-3.17' of git://git.infradead.org/users/pcmoore/selinux:
selinux: remove unused variabled in the netport, netnode, and netif caches
netlabel: fix the netlbl_catmap_setlong() dummy function
Values of extended attributes are stored as binary blobs. NULL-termination
of them isn't required. It just wastes disk space and confuses command-line
tools like getfattr because they have to print that zero byte at the end.
This patch removes terminating zero byte from initial security label in
smack_inode_init_security and cuts it out in function smack_inode_getsecurity
which is used by syscall getxattr. This change seems completely safe, because
function smk_parse_smack ignores everything after first zero byte.
Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
Zero-length security labels are invalid but kernel should handle them.
This patch fixes kernel panic after setting zero-length security labels:
# attr -S -s "SMACK64" -V "" file
And after writing zero-length string into smackfs files syslog and onlycp:
# python -c 'import os; os.write(1, "")' > /smack/syslog
The problem is caused by brain-damaged logic in function smk_parse_smack()
which takes pointer to buffer and its length but if length below or equal zero
it thinks that the buffer is zero-terminated. Unfortunately callers of this
function are widely used and proper fix requires serious refactoring.
Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
Security operation ->inode_listsecurity is used for generating list of
available extended attributes for syscall listxattr. Currently it's used
only in nfs4 or if filesystem doesn't provide i_op->listxattr.
The list is the set of NULL-terminated names, one after the other.
This method must include zero byte at the and into result.
Also this function must return length even if string does not fit into
output buffer or it is NULL, see similar method in selinux and man listxattr.
Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
David Howells