Any process is able to send netlink messages with invalid types.
Make the warning rate-limited to prevent too much log spam.
The warning is supposed to help to find misbehaving programs, so
print the triggering command name and pid.
Reported-by: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
[PM: subject line tweak to make checkpatch.pl happy]
Signed-off-by: Paul Moore <pmoore@redhat.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>
When fetching an inode's security label, check if it is still valid, and
try reloading it if it is not. Reloading will fail when we are in RCU
context which doesn't allow sleeping, or when we can't find a dentry for
the inode. (Reloading happens via iop->getxattr which takes a dentry
parameter.) When reloading fails, continue using the old, invalid
label.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Add a hook to invalidate an inode's security label when the cached
information becomes invalid.
Add the new hook in selinux: set a flag when a security label becomes
invalid.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Add functions dentry_security and inode_security for accessing
inode->i_security. These functions initially don't do much, but they
will later be used to revalidate the security labels when necessary.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Make the inode argument of the inode_getsecid hook non-const so that we
can use it to revalidate invalid security labels.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Make the inode argument of the inode_getsecurity hook non-const so that
we can use it to revalidate invalid security labels.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
TPM2 supports authorization policies, which are essentially
combinational logic statements repsenting the conditions where the data
can be unsealed based on the TPM state. This patch enables to use
authorization policies to seal trusted keys.
Two following new options have been added for trusted keys:
* 'policydigest=': provide an auth policy digest for sealing.
* 'policyhandle=': provide a policy session handle for unsealing.
If 'hash=' option is supplied after 'policydigest=' option, this
will result an error because the state of the option would become
mixed.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
Added 'hash=' option for selecting the hash algorithm for add_key()
syscall and documentation for it.
Added entry for sm3-256 to the following tables in order to support
TPM_ALG_SM3_256:
* hash_algo_name
* hash_digest_size
Includes support for the following hash algorithms:
* sha1
* sha256
* sha384
* sha512
* sm3-256
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
The trusted keys option parsing allows specifying the same option
multiple times. The last option value specified is used.
This is problematic because:
* No gain.
* This makes complicated to specify options that are dependent on other
options.
This patch changes the behavior in a way that option can be specified
only once.
Reported-by: James Morris James Morris <jmorris@namei.org>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
This fixes CVE-2015-7550.
There's a race between keyctl_read() and keyctl_revoke(). If the revoke
happens between keyctl_read() checking the validity of a key and the key's
semaphore being taken, then the key type read method will see a revoked key.
This causes a problem for the user-defined key type because it assumes in
its read method that there will always be a payload in a non-revoked key
and doesn't check for a NULL pointer.
Fix this by making keyctl_read() check the validity of a key after taking
semaphore instead of before.
I think the bug was introduced with the original keyrings code.
This was discovered by a multithreaded test program generated by syzkaller
(http://github.com/google/syzkaller). Here's a cleaned up version:
#include <sys/types.h>
#include <keyutils.h>
#include <pthread.h>
void *thr0(void *arg)
{
key_serial_t key = (unsigned long)arg;
keyctl_revoke(key);
return 0;
}
void *thr1(void *arg)
{
key_serial_t key = (unsigned long)arg;
char buffer[16];
keyctl_read(key, buffer, 16);
return 0;
}
int main()
{
key_serial_t key = add_key("user", "%", "foo", 3, KEY_SPEC_USER_KEYRING);
pthread_t th[5];
pthread_create(&th[0], 0, thr0, (void *)(unsigned long)key);
pthread_create(&th[1], 0, thr1, (void *)(unsigned long)key);
pthread_create(&th[2], 0, thr0, (void *)(unsigned long)key);
pthread_create(&th[3], 0, thr1, (void *)(unsigned long)key);
pthread_join(th[0], 0);
pthread_join(th[1], 0);
pthread_join(th[2], 0);
pthread_join(th[3], 0);
return 0;
}
Build as:
cc -o keyctl-race keyctl-race.c -lkeyutils -lpthread
Run as:
while keyctl-race; do :; done
as it may need several iterations to crash the kernel. The crash can be
summarised as:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
IP: [<ffffffff81279b08>] user_read+0x56/0xa3
...
Call Trace:
[<ffffffff81276aa9>] keyctl_read_key+0xb6/0xd7
[<ffffffff81277815>] SyS_keyctl+0x83/0xe0
[<ffffffff815dbb97>] entry_SYSCALL_64_fastpath+0x12/0x6f
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
Smack security handler for sendmsg() syscall
is vulnerable to type confusion issue what
can allow to privilege escalation into root
or cause denial of service.
A malicious attacker can create socket of one
type for example AF_UNIX and pass is into
sendmsg() function ensuring that this is
AF_INET socket.
Remedy
Do not trust user supplied data.
Proposed fix below.
Signed-off-by: Roman Kubiak <r.kubiak@samsung.com>
Signed-off-by: Mateusz Fruba <m.fruba@samsung.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
While creating a temporary list of new rules, the ima_appraise flag is
updated, but not reverted on failure to append the new rules to the
existing policy. This patch defines temp_ima_appraise flag. Only when
the new rules are appended to the policy is the flag updated.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Petko Manolov <petkan@mip-labs.com>
Set the KEY_FLAGS_KEEP on the .ima_blacklist to prevent userspace
from removing keys from the keyring.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Userspace should not be allowed to remove keys from certain keyrings
(eg. blacklist), though the keys themselves can expire.
This patch defines a new key flag named KEY_FLAG_KEEP to prevent
userspace from being able to unlink, revoke, invalidate or timed
out a key on a keyring. When this flag is set on the keyring, all
keys subsequently added are flagged.
In addition, when this flag is set, the keyring itself can not be
cleared.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: David Howells <dhowells@redhat.com>
It is often useful to be able to read back the IMA policy. It is
even more important after introducing CONFIG_IMA_WRITE_POLICY.
This option allows the root user to see the current policy rules.
Signed-off-by: Zbigniew Jasinski <z.jasinski@samsung.com>
Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This option creates IMA MOK and blacklist keyrings. IMA MOK is an
intermediate keyring that sits between .system and .ima keyrings,
effectively forming a simple CA hierarchy. To successfully import a key
into .ima_mok it must be signed by a key which CA is in .system keyring.
On turn any key that needs to go in .ima keyring must be signed by CA in
either .system or .ima_mok keyrings. IMA MOK is empty at kernel boot.
IMA blacklist keyring contains all revoked IMA keys. It is consulted
before any other keyring. If the search is successful the requested
operation is rejected and error is returned to the caller.
Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The new rules get appended to the original policy, forming a queue.
The new rules are first added to a temporary list, which on error
get released without disturbing the normal IMA operations. On
success both lists (the current policy and the new rules) are spliced.
IMA policy reads are many orders of magnitude more numerous compared to
writes, the match code is RCU protected. The updater side also does
list splice in RCU manner.
Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The newly added EVM_LOAD_X509 code can be configured even if
CONFIG_EVM is disabled, but that causes a link error:
security/built-in.o: In function `integrity_load_keys':
digsig_asymmetric.c:(.init.text+0x400): undefined reference to `evm_load_x509'
This adds a Kconfig dependency to ensure it is only enabled when
CONFIG_EVM is set as well.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 2ce523eb89 ("evm: load x509 certificate from the kernel")
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
The EVM verification status is cached in iint->evm_status and if it
was successful, never re-verified again when IMA passes the 'iint' to
evm_verifyxattr().
When file attributes or extended attributes change, we may wish to
re-verify EVM integrity as well. For example, after setting a digital
signature we may need to re-verify the signature and update the
iint->flags that there is an EVM signature.
This patch enables that by resetting evm_status to INTEGRITY_UKNOWN
state.
Changes in v2:
* Flag setting moved to EVM layer
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
A crypto HW kernel module can possibly initialize the EVM key from the
kernel __init code to enable EVM before calling the 'init' process.
This patch provides a function evm_set_key() to set the EVM key
directly without using the KEY subsystem.
Changes in v4:
* kernel-doc style for evm_set_key
Changes in v3:
* error reporting moved to evm_set_key
* EVM_INIT_HMAC moved to evm_set_key
* added bitop to prevent key setting race
Changes in v2:
* use size_t for key size instead of signed int
* provide EVM_MAX_KEY_SIZE macro in <linux/evm.h>
* provide EVM_MIN_KEY_SIZE macro in <linux/evm.h>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
In order to enable EVM before starting the 'init' process,
evm_initialized needs to be non-zero. Previously non-zero indicated
that the HMAC key was loaded. When EVM loads the X509 before calling
'init', with this patch it is now possible to enable EVM to start
signature based verification.
This patch defines bits to enable EVM if a key of any type is loaded.
Changes in v3:
* print error message if key is not set
Changes in v2:
* EVM_STATE_KEY_SET replaced by EVM_INIT_HMAC
* EVM_STATE_X509_SET replaced by EVM_INIT_X509
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch defines a configuration option and the evm_load_x509() hook
to load an X509 certificate onto the EVM trusted kernel keyring.
Changes in v4:
* Patch description updated
Changes in v3:
* Removed EVM_X509_PATH definition. CONFIG_EVM_X509_PATH is used
directly.
Changes in v2:
* default key patch changed to /etc/keys
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Vladis Dronov
Andrew Perepechko
Andreas Gruenbacher
Jarkko Sakkinen
David Howells
Roman Kubiak
Paul Gortmaker
Mimi Zohar
Petko Manolov
Arnd Bergmann
Dmitry Kasatkin