Commit Graph

742 Commits

Author SHA1 Message Date
Lakshmi Ramasubramanian 34e980bb83 IMA: Add audit log for failure conditions
process_buffer_measurement() and ima_alloc_key_entry() functions need to
log an audit message for auditing integrity measurement failures.

Add audit message in these two functions. Remove "pr_devel" log message
in process_buffer_measurement().

Sample audit messages:

[    6.303048] audit: type=1804 audit(1592506281.627:2): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=kernel op=measuring_key cause=ENOMEM comm="swapper/0" name=".builtin_trusted_keys" res=0 errno=-12

[    8.019432] audit: type=1804 audit(1592506283.344:10): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 op=measuring_kexec_cmdline cause=hashing_error comm="systemd" name="kexec-cmdline" res=0 errno=-22

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-16 21:48:36 -04:00
Lakshmi Ramasubramanian 2f845882ec integrity: Add errno field in audit message
Error code is not included in the audit messages logged by
the integrity subsystem.

Define a new function integrity_audit_message() that takes error code
in the "errno" parameter. Add "errno" field in the audit messages logged
by the integrity subsystem and set the value passed in the "errno"
parameter.

[    6.303048] audit: type=1804 audit(1592506281.627:2): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=kernel op=measuring_key cause=ENOMEM comm="swapper/0" name=".builtin_trusted_keys" res=0 errno=-12

[    7.987647] audit: type=1802 audit(1592506283.312:9): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 op=policy_update cause=completed comm="systemd" res=1 errno=0

[    8.019432] audit: type=1804 audit(1592506283.344:10): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 op=measuring_kexec_cmdline cause=hashing_error comm="systemd" name="kexec-cmdline" res=0 errno=-22

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Steve Grubb <sgrubb@redhat.com>
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-16 21:48:11 -04:00
Christoph Hellwig a1f9b1c043 integrity/ima: switch to using __kernel_read
__kernel_read has a bunch of additional sanity checks, and this moves
the set_fs out of non-core code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-08 08:27:57 +02:00
Maurizio Drocco 20c59ce010 ima: extend boot_aggregate with kernel measurements
Registers 8-9 are used to store measurements of the kernel and its
command line (e.g., grub2 bootloader with tpm module enabled). IMA
should include them in the boot aggregate. Registers 8-9 should be
only included in non-SHA1 digests to avoid ambiguity.

Signed-off-by: Maurizio Drocco <maurizio.drocco@ibm.com>
Reviewed-by: Bruno Meneguele <bmeneg@redhat.com>
Tested-by: Bruno Meneguele <bmeneg@redhat.com>  (TPM 1.2, TPM 2.0)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-06-24 20:47:24 -04:00
Gustavo A. R. Silva eb492c627a ima: Replace zero-length array with flexible-array
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://github.com/KSPP/linux/issues/21

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-06-15 23:08:32 -05:00
Linus Torvalds 923ea1631e ima: mprotect performance fix
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Merge tag 'integrity-v5.8-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity

Pull integrity fix from Mimi Zohar:
 "ima mprotect performance fix"

* tag 'integrity-v5.8-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  ima: fix mprotect checking
2020-06-12 12:02:41 -07:00
Mimi Zohar 4235b1a4ef ima: fix mprotect checking
Make sure IMA is enabled before checking mprotect change.  Addresses
report of a 3.7% regression of boot-time.dhcp.

Fixes: 8eb613c0b8 ("ima: verify mprotect change is consistent with mmap policy")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Tested-by: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-06-12 11:30:18 -04:00
Roberto Sassu 8b8c704d91 ima: Remove __init annotation from ima_pcrread()
Commit 6cc7c266e5 ("ima: Call ima_calc_boot_aggregate() in
ima_eventdigest_init()") added a call to ima_calc_boot_aggregate() so that
the digest can be recalculated for the boot_aggregate measurement entry if
the 'd' template field has been requested. For the 'd' field, only SHA1 and
MD5 digests are accepted.

Given that ima_eventdigest_init() does not have the __init annotation, all
functions called should not have it. This patch removes __init from
ima_pcrread().

Cc: stable@vger.kernel.org
Fixes:  6cc7c266e5 ("ima: Call ima_calc_boot_aggregate() in ima_eventdigest_init()")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-07 16:03:09 -07:00
Linus Torvalds 3c0ad98c2e integrity-v5.8
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Merge tag 'integrity-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity

Pull integrity updates from Mimi Zohar:
 "The main changes are extending the TPM 2.0 PCR banks with bank
  specific file hashes, calculating the "boot_aggregate" based on other
  TPM PCR banks, using the default IMA hash algorithm, instead of SHA1,
  as the basis for the cache hash table key, and preventing the mprotect
  syscall to circumvent an IMA mmap appraise policy rule.

   - In preparation for extending TPM 2.0 PCR banks with bank specific
     digests, commit 0b6cf6b97b ("tpm: pass an array of
     tpm_extend_digest structures to tpm_pcr_extend()") modified
     tpm_pcr_extend(). The original SHA1 file digests were
     padded/truncated, before being extended into the other TPM PCR
     banks. This pull request calculates and extends the TPM PCR banks
     with bank specific file hashes completing the above change.

   - The "boot_aggregate", the first IMA measurement list record, is the
     "trusted boot" link between the pre-boot environment and the
     running OS. With TPM 2.0, the "boot_aggregate" record is not
     limited to being based on the SHA1 TPM PCR bank, but can be
     calculated based on any enabled bank, assuming the hash algorithm
     is also enabled in the kernel.

  Other changes include the following and five other bug fixes/code
  clean up:

   - supporting both a SHA1 and a larger "boot_aggregate" digest in a
     custom template format containing both the the SHA1 ('d') and
     larger digests ('d-ng') fields.

   - Initial hash table key fix, but additional changes would be good"

* tag 'integrity-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  ima: Directly free *entry in ima_alloc_init_template() if digests is NULL
  ima: Call ima_calc_boot_aggregate() in ima_eventdigest_init()
  ima: Directly assign the ima_default_policy pointer to ima_rules
  ima: verify mprotect change is consistent with mmap policy
  evm: Fix possible memory leak in evm_calc_hmac_or_hash()
  ima: Set again build_ima_appraise variable
  ima: Remove redundant policy rule set in add_rules()
  ima: Fix ima digest hash table key calculation
  ima: Use ima_hash_algo for collision detection in the measurement list
  ima: Calculate and extend PCR with digests in ima_template_entry
  ima: Allocate and initialize tfm for each PCR bank
  ima: Switch to dynamically allocated buffer for template digests
  ima: Store template digest directly in ima_template_entry
  ima: Evaluate error in init_ima()
  ima: Switch to ima_hash_algo for boot aggregate
2020-06-06 09:39:05 -07:00
Roberto Sassu 42413b4980 ima: Directly free *entry in ima_alloc_init_template() if digests is NULL
To support multiple template digests, the static array entry->digest has
been replaced with a dynamically allocated array in commit aa724fe18a
("ima: Switch to dynamically allocated buffer for template digests"). The
array is allocated in ima_alloc_init_template() and if the returned pointer
is NULL, ima_free_template_entry() is called.

However, (*entry)->template_desc is not yet initialized while it is used by
ima_free_template_entry(). This patch fixes the issue by directly freeing
*entry without calling ima_free_template_entry().

Fixes: aa724fe18a ("ima: Switch to dynamically allocated buffer for template digests")
Reported-by: syzbot+223310b454ba6b75974e@syzkaller.appspotmail.com
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-06-05 06:04:11 -04:00
Roberto Sassu 6cc7c266e5 ima: Call ima_calc_boot_aggregate() in ima_eventdigest_init()
If the template field 'd' is chosen and the digest to be added to the
measurement entry was not calculated with SHA1 or MD5, it is
recalculated with SHA1, by using the passed file descriptor. However, this
cannot be done for boot_aggregate, because there is no file descriptor.

This patch adds a call to ima_calc_boot_aggregate() in
ima_eventdigest_init(), so that the digest can be recalculated also for the
boot_aggregate entry.

Cc: stable@vger.kernel.org # 3.13.x
Fixes: 3ce1217d6c ("ima: define template fields library and new helpers")
Reported-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-06-03 17:20:43 -04:00
Roberto Sassu 067a436b1b ima: Directly assign the ima_default_policy pointer to ima_rules
This patch prevents the following oops:

[   10.771813] BUG: kernel NULL pointer dereference, address: 0000000000000
[...]
[   10.779790] RIP: 0010:ima_match_policy+0xf7/0xb80
[...]
[   10.798576] Call Trace:
[   10.798993]  ? ima_lsm_policy_change+0x2b0/0x2b0
[   10.799753]  ? inode_init_owner+0x1a0/0x1a0
[   10.800484]  ? _raw_spin_lock+0x7a/0xd0
[   10.801592]  ima_must_appraise.part.0+0xb6/0xf0
[   10.802313]  ? ima_fix_xattr.isra.0+0xd0/0xd0
[   10.803167]  ima_must_appraise+0x4f/0x70
[   10.804004]  ima_post_path_mknod+0x2e/0x80
[   10.804800]  do_mknodat+0x396/0x3c0

It occurs when there is a failure during IMA initialization, and
ima_init_policy() is not called. IMA hooks still call ima_match_policy()
but ima_rules is NULL. This patch prevents the crash by directly assigning
the ima_default_policy pointer to ima_rules when ima_rules is defined. This
wouldn't alter the existing behavior, as ima_rules is always set at the end
of ima_init_policy().

Cc: stable@vger.kernel.org # 3.7.x
Fixes: 07f6a79415 ("ima: add appraise action keywords and default rules")
Reported-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-06-03 14:54:35 -04:00
Mimi Zohar 8eb613c0b8 ima: verify mprotect change is consistent with mmap policy
Files can be mmap'ed read/write and later changed to execute to circumvent
IMA's mmap appraise policy rules.  Due to locking issues (mmap semaphore
would be taken prior to i_mutex), files can not be measured or appraised at
this point.  Eliminate this integrity gap, by denying the mprotect
PROT_EXECUTE change, if an mmap appraise policy rule exists.

On mprotect change success, return 0.  On failure, return -EACESS.

Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-22 14:41:04 -04:00
Dan Carpenter 8433856947 evm: Fix a small race in init_desc()
The IS_ERR_OR_NULL() function has two conditions and if we got really
unlucky we could hit a race where "ptr" started as an error pointer and
then was set to NULL.  Both conditions would be false even though the
pointer at the end was NULL.

This patch fixes the problem by ensuring that "*tfm" can only be NULL
or valid.  I have introduced a "tmp_tfm" variable to make that work.  I
also reversed a condition and pulled the code in one tab.

Reported-by: Roberto Sassu <roberto.sassu@huawei.com>
Fixes: 53de3b080d ("evm: Check also if *tfm is an error pointer in init_desc()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Roberto Sassu <roberto.sassu@huawei.com>
Acked-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-14 19:55:54 -04:00
Roberto Sassu 0c4395fb2a evm: Fix possible memory leak in evm_calc_hmac_or_hash()
Don't immediately return if the signature is portable and security.ima is
not present. Just set error so that memory allocated is freed before
returning from evm_calc_hmac_or_hash().

Fixes: 50b977481f ("EVM: Add support for portable signature format")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 23:36:25 -04:00
Krzysztof Struczynski b59fda449c ima: Set again build_ima_appraise variable
After adding the new add_rule() function in commit c52657d93b
("ima: refactor ima_init_policy()"), all appraisal flags are added to the
temp_ima_appraise variable. Revert to the previous behavior instead of
removing build_ima_appraise, to benefit from the protection offered by
__ro_after_init.

The mentioned commit introduced a bug, as it makes all the flags
modifiable, while build_ima_appraise flags can be protected with
__ro_after_init.

Cc: stable@vger.kernel.org # 5.0.x
Fixes: c52657d93b ("ima: refactor ima_init_policy()")
Co-developed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 22:54:09 -04:00
Krzysztof Struczynski 6ee28442a4 ima: Remove redundant policy rule set in add_rules()
Function ima_appraise_flag() returns the flag to be set in
temp_ima_appraise depending on the hook identifier passed as an argument.
It is not necessary to set the flag again for the POLICY_CHECK hook.

Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 22:54:08 -04:00
Krzysztof Struczynski 1129d31b55 ima: Fix ima digest hash table key calculation
Function hash_long() accepts unsigned long, while currently only one byte
is passed from ima_hash_key(), which calculates a key for ima_htable.

Given that hashing the digest does not give clear benefits compared to
using the digest itself, remove hash_long() and return the modulus
calculated on the first two bytes of the digest with the number of slots.
Also reduce the depth of the hash table by doubling the number of slots.

Cc: stable@vger.kernel.org
Fixes: 3323eec921 ("integrity: IMA as an integrity service provider")
Co-developed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Acked-by: David.Laight@aculab.com (big endian system concerns)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 22:54:07 -04:00
Madhuparna Bhowmik 770f60586d evm: Fix RCU list related warnings
This patch fixes the following warning and few other instances of
traversal of evm_config_xattrnames list:

[   32.848432] =============================
[   32.848707] WARNING: suspicious RCU usage
[   32.848966] 5.7.0-rc1-00006-ga8d5875ce5f0b #1 Not tainted
[   32.849308] -----------------------------
[   32.849567] security/integrity/evm/evm_main.c:231 RCU-list traversed in non-reader section!!

Since entries are only added to the list and never deleted, use
list_for_each_entry_lockless() instead of list_for_each_entry_rcu for
traversing the list.  Also, add a relevant comment in evm_secfs.c to
indicate this fact.

Reported-by: kernel test robot <lkp@intel.com>
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org> (RCU viewpoint)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 21:36:32 -04:00
Roberto Sassu 2e3a34e9f4 ima: Fix return value of ima_write_policy()
This patch fixes the return value of ima_write_policy() when a new policy
is directly passed to IMA and the current policy requires appraisal of the
file containing the policy. Currently, if appraisal is not in ENFORCE mode,
ima_write_policy() returns 0 and leads user space applications to an
endless loop. Fix this issue by denying the operation regardless of the
appraisal mode.

Cc: stable@vger.kernel.org # 4.10.x
Fixes: 19f8a84713 ("ima: measure and appraise the IMA policy itself")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 21:36:31 -04:00
Roberto Sassu 53de3b080d evm: Check also if *tfm is an error pointer in init_desc()
This patch avoids a kernel panic due to accessing an error pointer set by
crypto_alloc_shash(). It occurs especially when there are many files that
require an unsupported algorithm, as it would increase the likelihood of
the following race condition:

Task A: *tfm = crypto_alloc_shash() <= error pointer
Task B: if (*tfm == NULL) <= *tfm is not NULL, use it
Task B: rc = crypto_shash_init(desc) <= panic
Task A: *tfm = NULL

This patch uses the IS_ERR_OR_NULL macro to determine whether or not a new
crypto context must be created.

Cc: stable@vger.kernel.org
Fixes: d46eb36995 ("evm: crypto hash replaced by shash")
Co-developed-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 21:30:58 -04:00
Roberto Sassu 0014cc04e8 ima: Set file->f_mode instead of file->f_flags in ima_calc_file_hash()
Commit a408e4a86b ("ima: open a new file instance if no read
permissions") tries to create a new file descriptor to calculate a file
digest if the file has not been opened with O_RDONLY flag. However, if a
new file descriptor cannot be obtained, it sets the FMODE_READ flag to
file->f_flags instead of file->f_mode.

This patch fixes this issue by replacing f_flags with f_mode as it was
before that commit.

Cc: stable@vger.kernel.org # 4.20.x
Fixes: a408e4a86b ("ima: open a new file instance if no read permissions")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 21:30:58 -04:00
Roberto Sassu 2592677c04 ima: Use ima_hash_algo for collision detection in the measurement list
Before calculating a digest for each PCR bank, collisions were detected
with a SHA1 digest. This patch includes ima_hash_algo among the algorithms
used to calculate the template digest and checks collisions on that digest.

The position in the measurement entry array of the template digest
calculated with the IMA default hash algorithm is stored in the
ima_hash_algo_idx global variable and is determined at IMA initialization
time.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Roberto Sassu 1ea973df6e ima: Calculate and extend PCR with digests in ima_template_entry
This patch modifies ima_calc_field_array_hash() to calculate a template
digest for each allocated PCR bank and SHA1. It also passes the tpm_digest
array of the template entry to ima_pcr_extend() or in case of a violation,
the pre-initialized digests array filled with 0xff.

Padding with zeros is still done if the mapping between TPM algorithm ID
and crypto ID is unknown.

This patch calculates again the template digest when a measurement list is
restored. Copying only the SHA1 digest (due to the limitation of the
current measurement list format) is not sufficient, as hash collision
detection will be done on the digest calculated with the IMA default hash
algorithm.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Roberto Sassu 6d94809af6 ima: Allocate and initialize tfm for each PCR bank
This patch creates a crypto_shash structure for each allocated PCR bank and
for SHA1 if a bank with that algorithm is not currently allocated.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Roberto Sassu aa724fe18a ima: Switch to dynamically allocated buffer for template digests
This patch dynamically allocates the array of tpm_digest structures in
ima_alloc_init_template() and ima_restore_template_data(). The size of the
array is equal to the number of PCR banks plus ima_extra_slots, to make
room for SHA1 and the IMA default hash algorithm, when PCR banks with those
algorithms are not allocated.

Calculating the SHA1 digest is mandatory, as SHA1 still remains the default
hash algorithm for the measurement list. When IMA will support the Crypto
Agile format, remaining digests will be also provided.

The position in the measurement entry array of the SHA1 digest is stored in
the ima_sha1_idx global variable and is determined at IMA initialization
time.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Roberto Sassu 7ca79645a1 ima: Store template digest directly in ima_template_entry
In preparation for the patch that calculates a digest for each allocated
PCR bank, this patch passes to ima_calc_field_array_hash() the
ima_template_entry structure, so that digests can be directly stored in
that structure instead of ima_digest_data.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Roberto Sassu e144d6b265 ima: Evaluate error in init_ima()
Evaluate error in init_ima() before register_blocking_lsm_notifier() and
return if not zero.

Cc: stable@vger.kernel.org # 5.3.x
Fixes: b169424551 ("ima: use the lsm policy update notifier")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Roberto Sassu 6f1a1d103b ima: Switch to ima_hash_algo for boot aggregate
boot_aggregate is the first entry of IMA measurement list. Its purpose is
to link pre-boot measurements to IMA measurements. As IMA was designed to
work with a TPM 1.2, the SHA1 PCR bank was always selected even if a
TPM 2.0 with support for stronger hash algorithms is available.

This patch first tries to find a PCR bank with the IMA default hash
algorithm. If it does not find it, it selects the SHA256 PCR bank for
TPM 2.0 and SHA1 for TPM 1.2. Ultimately, it selects SHA1 also for TPM 2.0
if the SHA256 PCR bank is not found.

If none of the PCR banks above can be found, boot_aggregate file digest is
filled with zeros, as for TPM bypass, making it impossible to perform a
remote attestation of the system.

Cc: stable@vger.kernel.org # 5.1.x
Fixes: 879b589210 ("tpm: retrieve digest size of unknown algorithms with PCR read")
Reported-by: Jerry Snitselaar <jsnitsel@redhat.com>
Suggested-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Linus Torvalds 7f218319ca Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:
 "Just a couple of updates for linux-5.7:

   - A new Kconfig option to enable IMA architecture specific runtime
     policy rules needed for secure and/or trusted boot, as requested.

   - Some message cleanup (eg. pr_fmt, additional error messages)"

* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  ima: add a new CONFIG for loading arch-specific policies
  integrity: Remove duplicate pr_fmt definitions
  IMA: Add log statements for failure conditions
  IMA: Update KBUILD_MODNAME for IMA files to ima
2020-04-02 14:49:46 -07:00
Nayna Jain 9e2b4be377 ima: add a new CONFIG for loading arch-specific policies
Every time a new architecture defines the IMA architecture specific
functions - arch_ima_get_secureboot() and arch_ima_get_policy(), the IMA
include file needs to be updated. To avoid this "noise", this patch
defines a new IMA Kconfig IMA_SECURE_AND_OR_TRUSTED_BOOT option, allowing
the different architectures to select it.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Philipp Rudo <prudo@linux.ibm.com> (s390)
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-03-12 07:43:57 -04:00
Tushar Sugandhi 555d6d71d5 integrity: Remove duplicate pr_fmt definitions
The #define for formatting log messages, pr_fmt, is duplicated in the
files under security/integrity.

This change moves the definition to security/integrity/integrity.h and
removes the duplicate definitions in the other files under
security/integrity.

With this change, the messages in the following files will be prefixed
with 'integrity'.

     security/integrity/platform_certs/platform_keyring.c
     security/integrity/platform_certs/load_powerpc.c
     security/integrity/platform_certs/load_uefi.c
     security/integrity/iint.c

     e.g. "integrity: Error adding keys to platform keyring %s\n"

And the messages in the following file will be prefixed with 'ima'.

     security/integrity/ima/ima_mok.c

     e.g. "ima: Allocating IMA blacklist keyring.\n"

For the rest of the files under security/integrity, there will be no
change in the message format.

Suggested-by: Shuah Khan <skhan@linuxfoundation.org>
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-02-28 14:32:58 -05:00
Tushar Sugandhi 72ec611c64 IMA: Add log statements for failure conditions
process_buffer_measurement() does not have log messages for failure
conditions.

This change adds a log statement in the above function.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-02-28 14:32:58 -05:00
Tushar Sugandhi e2bf6814be IMA: Update KBUILD_MODNAME for IMA files to ima
The kbuild Makefile specifies object files for vmlinux in the $(obj-y)
lists. These lists depend on the kernel configuration[1].

The kbuild Makefile for IMA combines the object files for IMA into a
single object file namely ima.o. All the object files for IMA should be
combined into ima.o. But certain object files are being added to their
own $(obj-y). This results in the log messages from those modules getting
prefixed with their respective base file name, instead of "ima". This is
inconsistent with the log messages from the IMA modules that are combined
into ima.o.

This change fixes the above issue.

[1] Documentation\kbuild\makefiles.rst

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-02-28 14:32:58 -05:00
Ingo Molnar e9765680a3 EFI updates for v5.7:
This time, the set of changes for the EFI subsystem is much larger than
 usual. The main reasons are:
 - Get things cleaned up before EFI support for RISC-V arrives, which will
   increase the size of the validation matrix, and therefore the threshold to
   making drastic changes,
 - After years of defunct maintainership, the GRUB project has finally started
   to consider changes from the distros regarding UEFI boot, some of which are
   highly specific to the way x86 does UEFI secure boot and measured boot,
   based on knowledge of both shim internals and the layout of bootparams and
   the x86 setup header. Having this maintenance burden on other architectures
   (which don't need shim in the first place) is hard to justify, so instead,
   we are introducing a generic Linux/UEFI boot protocol.
 
 Summary of changes:
 - Boot time GDT handling changes (Arvind)
 - Simplify handling of EFI properties table on arm64
 - Generic EFI stub cleanups, to improve command line handling, file I/O,
   memory allocation, etc.
 - Introduce a generic initrd loading method based on calling back into
   the firmware, instead of relying on the x86 EFI handover protocol or
   device tree.
 - Introduce a mixed mode boot method that does not rely on the x86 EFI
   handover protocol either, and could potentially be adopted by other
   architectures (if another one ever surfaces where one execution mode
   is a superset of another)
 - Clean up the contents of struct efi, and move out everything that
   doesn't need to be stored there.
 - Incorporate support for UEFI spec v2.8A changes that permit firmware
   implementations to return EFI_UNSUPPORTED from UEFI runtime services at
   OS runtime, and expose a mask of which ones are supported or unsupported
   via a configuration table.
 - Various documentation updates and minor code cleanups (Heinrich)
 - Partial fix for the lack of by-VA cache maintenance in the decompressor
   on 32-bit ARM. Note that these patches were deliberately put at the
   beginning so they can be used as a stable branch that will be shared with
   a PR containing the complete fix, which I will send to the ARM tree.
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Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi into efi/core

Pull EFI updates for v5.7 from Ard Biesheuvel:

This time, the set of changes for the EFI subsystem is much larger than
usual. The main reasons are:

 - Get things cleaned up before EFI support for RISC-V arrives, which will
   increase the size of the validation matrix, and therefore the threshold to
   making drastic changes,

 - After years of defunct maintainership, the GRUB project has finally started
   to consider changes from the distros regarding UEFI boot, some of which are
   highly specific to the way x86 does UEFI secure boot and measured boot,
   based on knowledge of both shim internals and the layout of bootparams and
   the x86 setup header. Having this maintenance burden on other architectures
   (which don't need shim in the first place) is hard to justify, so instead,
   we are introducing a generic Linux/UEFI boot protocol.

Summary of changes:

 - Boot time GDT handling changes (Arvind)

 - Simplify handling of EFI properties table on arm64

 - Generic EFI stub cleanups, to improve command line handling, file I/O,
   memory allocation, etc.

 - Introduce a generic initrd loading method based on calling back into
   the firmware, instead of relying on the x86 EFI handover protocol or
   device tree.

 - Introduce a mixed mode boot method that does not rely on the x86 EFI
   handover protocol either, and could potentially be adopted by other
   architectures (if another one ever surfaces where one execution mode
   is a superset of another)

 - Clean up the contents of struct efi, and move out everything that
   doesn't need to be stored there.

 - Incorporate support for UEFI spec v2.8A changes that permit firmware
   implementations to return EFI_UNSUPPORTED from UEFI runtime services at
   OS runtime, and expose a mask of which ones are supported or unsupported
   via a configuration table.

 - Various documentation updates and minor code cleanups (Heinrich)

 - Partial fix for the lack of by-VA cache maintenance in the decompressor
   on 32-bit ARM. Note that these patches were deliberately put at the
   beginning so they can be used as a stable branch that will be shared with
   a PR containing the complete fix, which I will send to the ARM tree.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-02-26 15:21:22 +01:00
Ard Biesheuvel 6b75d54d52 integrity: Check properly whether EFI GetVariable() is available
Testing the value of the efi.get_variable function pointer is not
the right way to establish whether the platform supports EFI
variables at runtime. Instead, use the newly added granular check
that can test for the presence of each EFI runtime service
individually.

Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23 21:59:42 +01:00
Tianjia Zhang 5780b9abd5 ima: add sm3 algorithm to hash algorithm configuration list
sm3 has been supported by the ima hash algorithm, but it is not
yet in the Kconfig configuration list. After adding, both ima and tpm2
can support sm3 well.

Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-02-18 07:35:49 -05:00
Javier Martinez Canillas 3be54d558c efi: Only print errors about failing to get certs if EFI vars are found
If CONFIG_LOAD_UEFI_KEYS is enabled, the kernel attempts to load the certs
from the db, dbx and MokListRT EFI variables into the appropriate keyrings.

But it just assumes that the variables will be present and prints an error
if the certs can't be loaded, even when is possible that the variables may
not exist. For example the MokListRT variable will only be present if shim
is used.

So only print an error message about failing to get the certs list from an
EFI variable if this is found. Otherwise these printed errors just pollute
the kernel log ring buffer with confusing messages like the following:

[    5.427251] Couldn't get size: 0x800000000000000e
[    5.427261] MODSIGN: Couldn't get UEFI db list
[    5.428012] Couldn't get size: 0x800000000000000e
[    5.428023] Couldn't get UEFI MokListRT

Reported-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-02-18 07:35:48 -05:00
Linus Torvalds 73a0bff205 Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull IMA updates from Mimi Zohar:
 "Two new features - measuring certificates and querying IMA for a file
  hash - and three bug fixes:

   - Measuring certificates is like the rest of IMA, based on policy,
     but requires loading a custom policy. Certificates loaded onto a
     keyring, for example during early boot, before a custom policy has
     been loaded, are queued and only processed after loading the custom
     policy.

   - IMA calculates and caches files hashes. Other kernel subsystems,
     and possibly kernel modules, are interested in accessing these
     cached file hashes.

  The bug fixes prevent classifying a file short read (e.g. shutdown) as
  an invalid file signature, add a missing blank when displaying the
  securityfs policy rules containing LSM labels, and, lastly, fix the
  handling of the IMA policy information for unknown LSM labels"

* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  IMA: Defined delayed workqueue to free the queued keys
  IMA: Call workqueue functions to measure queued keys
  IMA: Define workqueue for early boot key measurements
  IMA: pre-allocate buffer to hold keyrings string
  ima: ima/lsm policy rule loading logic bug fixes
  ima: add the ability to query the cached hash of a given file
  ima: Add a space after printing LSM rules for readability
  IMA: fix measuring asymmetric keys Kconfig
  IMA: Read keyrings= option from the IMA policy
  IMA: Add support to limit measuring keys
  KEYS: Call the IMA hook to measure keys
  IMA: Define an IMA hook to measure keys
  IMA: Add KEY_CHECK func to measure keys
  IMA: Check IMA policy flag
  ima: avoid appraise error for hash calc interrupt
2020-01-28 18:52:09 -08:00
Lakshmi Ramasubramanian 5b3014b952 IMA: Defined delayed workqueue to free the queued keys
Keys queued for measurement should be freed if a custom IMA policy
was not loaded.  Otherwise, the keys will remain queued forever
consuming kernel memory.

This patch defines a delayed workqueue to handle the above scenario.
The workqueue handler is setup to execute 5 minutes after IMA
initialization is completed.

If a custom IMA policy is loaded before the workqueue handler is
scheduled to execute, the workqueue task is cancelled and any queued keys
are processed for measurement.  But if a custom policy was not loaded then
the queued keys are just freed when the delayed workqueue handler is run.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Reported-by: kernel test robot <rong.a.chen@intel.com> # sleeping
function called from invalid context
Reported-by: kbuild test robot <lkp@intel.com> # redefinition of
ima_init_key_queue() function.
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-01-23 07:37:31 -05:00
Lakshmi Ramasubramanian 450d0fd515 IMA: Call workqueue functions to measure queued keys
Measuring keys requires a custom IMA policy to be loaded.  Keys should
be queued for measurement if a custom IMA policy is not yet loaded.
Keys queued for measurement, if any, should be processed when a custom
policy is loaded.

This patch updates the IMA hook function ima_post_key_create_or_update()
to queue the key if a custom IMA policy has not yet been loaded.  And,
ima_update_policy() function, which is called when a custom IMA policy
is loaded, is updated to process queued keys.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-01-23 07:35:25 -05:00
Lakshmi Ramasubramanian 9f81a2eda4 IMA: Define workqueue for early boot key measurements
Measuring keys requires a custom IMA policy to be loaded.  Keys created
or updated before a custom IMA policy is loaded should be queued and
will be processed after a custom policy is loaded.

This patch defines a workqueue for queuing keys when a custom IMA policy
has not yet been loaded.  An intermediate Kconfig boolean option namely
IMA_QUEUE_EARLY_BOOT_KEYS is used to declare the workqueue functions.

A flag namely ima_process_keys is used to check if the key should be
queued or should be processed immediately.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-01-23 07:35:11 -05:00
Lakshmi Ramasubramanian 5c7bac9fb2 IMA: pre-allocate buffer to hold keyrings string
ima_match_keyring() is called while holding rcu read lock. Since this
function executes in atomic context, it should not call any function
that can sleep (such as kstrdup()).

This patch pre-allocates a buffer to hold the keyrings string read from
the IMA policy and uses that to match the given keyring.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Fixes: e9085e0ad3 ("IMA: Add support to limit measuring keys")
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-01-22 15:22:51 -05:00
Janne Karhunen 483ec26eed ima: ima/lsm policy rule loading logic bug fixes
Keep the ima policy rules around from the beginning even if they appear
invalid at the time of loading, as they may become active after an lsm
policy load.  However, loading a custom IMA policy with unknown LSM
labels is only safe after we have transitioned from the "built-in"
policy rules to a custom IMA policy.

Patch also fixes the rule re-use during the lsm policy reload and makes
some prints a bit more human readable.

Changelog:
v4:
- Do not allow the initial policy load refer to non-existing lsm rules.
v3:
- Fix too wide policy rule matching for non-initialized LSMs
v2:
- Fix log prints

Fixes: b169424551 ("ima: use the lsm policy update notifier")
Cc: Casey Schaufler <casey@schaufler-ca.com>
Reported-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Janne Karhunen <janne.karhunen@gmail.com>
Signed-off-by: Konsta Karsisto <konsta.karsisto@gmail.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-01-22 15:22:51 -05:00
Florent Revest 6beea7afcc ima: add the ability to query the cached hash of a given file
This allows other parts of the kernel (perhaps a stacked LSM allowing
system monitoring, eg. the proposed KRSI LSM [1]) to retrieve the hash
of a given file from IMA if it's present in the iint cache.

It's true that the existence of the hash means that it's also in the
audit logs or in /sys/kernel/security/ima/ascii_runtime_measurements,
but it can be difficult to pull that information out for every
subsequent exec. This is especially true if a given host has been up
for a long time and the file was first measured a long time ago.

It should be kept in mind that this function gives access to cached
entries which can be removed, for instance on security_inode_free().

This is based on Peter Moody's patch:
 https://sourceforge.net/p/linux-ima/mailman/message/33036180/

[1] https://lkml.org/lkml/2019/9/10/393

Signed-off-by: Florent Revest <revest@google.com>
Reviewed-by: KP Singh <kpsingh@chromium.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-01-22 15:22:51 -05:00
Clay Chang 5350ceb0b7 ima: Add a space after printing LSM rules for readability
When reading ima_policy from securityfs, there is a missing
space between output string of LSM rules and the remaining
rules.

Signed-off-by: Clay Chang <clayc@hpe.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-01-22 15:22:51 -05:00
Lakshmi Ramasubramanian ea78979d30 IMA: fix measuring asymmetric keys Kconfig
As a result of the asymmetric public keys subtype Kconfig option being
defined as tristate, with the existing IMA Makefile, ima_asymmetric_keys.c
could be built as a kernel module.  To prevent this from happening, this
patch defines and uses an intermediate Kconfig boolean option named
IMA_MEASURE_ASYMMETRIC_KEYS.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: James.Bottomley <James.Bottomley@HansenPartnership.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reported-by: kbuild test robot <lkp@intel.com> # ima_asymmetric_keys.c
is built as a kernel module.
Fixes: 88e70da170 ("IMA: Define an IMA hook to measure keys")
Fixes: cb1aa3823c ("KEYS: Call the IMA hook to measure keys")
[zohar@linux.ibm.com: updated patch description]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-01-09 14:06:06 -05:00
Lakshmi Ramasubramanian 2b60c0eced IMA: Read keyrings= option from the IMA policy
Read "keyrings=" option, if specified in the IMA policy, and store in
the list of IMA rules when the configured IMA policy is read.

This patch defines a new policy token enum namely Opt_keyrings
and an option flag IMA_KEYRINGS for reading "keyrings=" option
from the IMA policy.

Updated ima_parse_rule() to parse "keyrings=" option in the policy.
Updated ima_policy_show() to display "keyrings=" option.

The following example illustrates how key measurement can be verified.

Sample "key" measurement rule in the IMA policy:

measure func=KEY_CHECK uid=0 keyrings=.ima|.evm template=ima-buf

Display "key" measurement in the IMA measurement list:

cat /sys/kernel/security/ima/ascii_runtime_measurements

10 faf3...e702 ima-buf sha256:27c915b8ddb9fae7214cf0a8a7043cc3eeeaa7539bcb136f8427067b5f6c3b7b .ima 308202863082...4aee

Verify "key" measurement data for a key added to ".ima" keyring:

cat /sys/kernel/security/integrity/ima/ascii_runtime_measurements | grep -m 1 "\.ima" | cut -d' ' -f 6 | xxd -r -p |tee ima-cert.der | sha256sum | cut -d' ' -f 1

The output of the above command should match the template hash
of the first "key" measurement entry in the IMA measurement list for
the key added to ".ima" keyring.

The file namely "ima-cert.der" generated by the above command
should be a valid x509 certificate (in DER format) and should match
the one that was used to import the key to the ".ima" keyring.
The certificate file can be verified using openssl tool.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-12-12 08:53:50 -05:00
Lakshmi Ramasubramanian e9085e0ad3 IMA: Add support to limit measuring keys
Limit measuring keys to those keys being loaded onto a given set of
keyrings only and when the user id (uid) matches if uid is specified
in the policy.

This patch defines a new IMA policy option namely "keyrings=" that
can be used to specify a set of keyrings. If this option is specified
in the policy for "measure func=KEY_CHECK" then only the keys
loaded onto a keyring given in the "keyrings=" option are measured.

If uid is specified in the policy then the key is measured only if
the current user id matches the one specified in the policy.

Added a new parameter namely "keyring" (name of the keyring) to
process_buffer_measurement(). The keyring name is passed to
ima_get_action() to determine the required action.
ima_match_rules() is updated to check keyring in the policy, if
specified, for KEY_CHECK function.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-12-12 08:53:50 -05:00
Lakshmi Ramasubramanian 88e70da170 IMA: Define an IMA hook to measure keys
Measure asymmetric keys used for verifying file signatures,
certificates, etc.

This patch defines a new IMA hook namely ima_post_key_create_or_update()
to measure the payload used to create a new asymmetric key or
update an existing asymmetric key.

Asymmetric key structure is defined only when
CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE is defined. Since the IMA hook
measures asymmetric keys, the IMA hook is defined in a new file namely
ima_asymmetric_keys.c which is built only if
CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE is defined.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-12-12 08:53:50 -05:00
Lakshmi Ramasubramanian 5808611ccc IMA: Add KEY_CHECK func to measure keys
Measure keys loaded onto any keyring.

This patch defines a new IMA policy func namely KEY_CHECK to
measure keys. Updated ima_match_rules() to check for KEY_CHECK
and ima_parse_rule() to handle KEY_CHECK.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-12-12 08:53:50 -05:00
Lakshmi Ramasubramanian c5563bad88 IMA: Check IMA policy flag
process_buffer_measurement() may be called prior to IMA being
initialized (for instance, when the IMA hook is called when
a key is added to the .builtin_trusted_keys keyring), which
would result in a kernel panic.

This patch adds the check in process_buffer_measurement()
to return immediately if IMA is not initialized yet.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-12-12 08:53:50 -05:00
Patrick Callaghan 96c9e1de99 ima: avoid appraise error for hash calc interrupt
The integrity_kernel_read() call in ima_calc_file_hash_tfm() can return
a value of 0 before all bytes of the file are read. A value of 0 would
normally indicate an EOF. This has been observed if a user process is
causing a file appraisal and is terminated with a SIGTERM signal. The
most common occurrence of seeing the problem is if a shutdown or systemd
reload is initiated while files are being appraised.

The problem is similar to commit <f5e1040196db> (ima: always return
negative code for error) that fixed the problem in
ima_calc_file_hash_atfm().

Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Patrick Callaghan <patrickc@linux.ibm.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-12-12 08:52:05 -05:00
Pankaj Bharadiya c593642c8b treewide: Use sizeof_field() macro
Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except
at places where these are defined. Later patches will remove the unused
definition of FIELD_SIZEOF().

This patch is generated using following script:

EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h"

git grep -l -e "\bFIELD_SIZEOF\b" | while read file;
do

	if [[ "$file" =~ $EXCLUDE_FILES ]]; then
		continue
	fi
	sed -i  -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file;
done

Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: David Miller <davem@davemloft.net> # for net
2019-12-09 10:36:44 -08:00
YueHaibing 6f090192f8 x86/efi: remove unused variables
commit ad723674d6 ("x86/efi: move common keyring handler functions
to new file") leave this unused.

Fixes: ad723674d6 ("x86/efi: move common keyring handler functions to new file")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20191115130830.13320-1-yuehaibing@huawei.com
2019-11-29 22:23:46 +11:00
Nayna Jain 8220e22d11 powerpc: Load firmware trusted keys/hashes into kernel keyring
The keys used to verify the Host OS kernel are managed by firmware as
secure variables. This patch loads the verification keys into the
.platform keyring and revocation hashes into .blacklist keyring. This
enables verification and loading of the kernels signed by the boot
time keys which are trusted by firmware.

Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Eric Richter <erichte@linux.ibm.com>
[mpe: Search by compatible in load_powerpc_certs(), not using format]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1573441836-3632-5-git-send-email-nayna@linux.ibm.com
2019-11-13 00:33:23 +11:00
Nayna Jain ad723674d6 x86/efi: move common keyring handler functions to new file
The handlers to add the keys to the .platform keyring and blacklisted
hashes to the .blacklist keyring is common for both the uefi and powerpc
mechanisms of loading the keys/hashes from the firmware.

This patch moves the common code from load_uefi.c to keyring_handler.c

Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Acked-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Eric Richter <erichte@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1573441836-3632-4-git-send-email-nayna@linux.ibm.com
2019-11-13 00:33:23 +11:00
Nayna Jain 273df864cf ima: Check against blacklisted hashes for files with modsig
Asymmetric private keys are used to sign multiple files. The kernel
currently supports checking against blacklisted keys. However, if the
public key is blacklisted, any file signed by the blacklisted key will
automatically fail signature verification. Blacklisting the public key
is not fine enough granularity, as we might want to only blacklist a
particular file.

This patch adds support for checking against the blacklisted hash of
the file, without the appended signature, based on the IMA policy. It
defines a new policy option "appraise_flag=check_blacklist".

In addition to the blacklisted binary hashes stored in the firmware
"dbx" variable, the Linux kernel may be configured to load blacklisted
binary hashes onto the .blacklist keyring as well. The following
example shows how to blacklist a specific kernel module hash.

  $ sha256sum kernel/kheaders.ko
  77fa889b35a05338ec52e51591c1b89d4c8d1c99a21251d7c22b1a8642a6bad3
  kernel/kheaders.ko

  $ grep BLACKLIST .config
  CONFIG_SYSTEM_BLACKLIST_KEYRING=y
  CONFIG_SYSTEM_BLACKLIST_HASH_LIST="blacklist-hash-list"

  $ cat certs/blacklist-hash-list
  "bin:77fa889b35a05338ec52e51591c1b89d4c8d1c99a21251d7c22b1a8642a6bad3"

Update the IMA custom measurement and appraisal policy
rules (/etc/ima-policy):

  measure func=MODULE_CHECK template=ima-modsig
  appraise func=MODULE_CHECK appraise_flag=check_blacklist
  appraise_type=imasig|modsig

After building, installing, and rebooting the kernel:

   545660333 ---lswrv      0     0   \_ blacklist:
  bin:77fa889b35a05338ec52e51591c1b89d4c8d1c99a21251d7c22b1a8642a6bad3

  measure func=MODULE_CHECK template=ima-modsig
  appraise func=MODULE_CHECK appraise_flag=check_blacklist
  appraise_type=imasig|modsig

  modprobe: ERROR: could not insert 'kheaders': Permission denied

  10 0c9834db5a0182c1fb0cdc5d3adcf11a11fd83dd ima-sig
  sha256:3bc6ed4f0b4d6e31bc1dbc9ef844605abc7afdc6d81a57d77a1ec9407997c40
  2 /usr/lib/modules/5.4.0-rc3+/kernel/kernel/kheaders.ko

  10 82aad2bcc3fa8ed94762356b5c14838f3bcfa6a0 ima-modsig
  sha256:3bc6ed4f0b4d6e31bc1dbc9ef844605abc7afdc6d81a57d77a1ec9407997c40
  2 /usr/lib/modules/5.4.0rc3+/kernel/kernel/kheaders.ko  sha256:77fa889b3
  5a05338ec52e51591c1b89d4c8d1c99a21251d7c22b1a8642a6bad3
  3082029a06092a864886f70d010702a082028b30820287020101310d300b0609608648
  016503040201300b06092a864886f70d01070131820264....

  10 25b72217cc1152b44b134ce2cd68f12dfb71acb3 ima-buf
  sha256:8b58427fedcf8f4b20bc8dc007f2e232bf7285d7b93a66476321f9c2a3aa132
  b blacklisted-hash
  77fa889b35a05338ec52e51591c1b89d4c8d1c99a21251d7c22b1a8642a6bad3

Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
[zohar@linux.ibm.com: updated patch description]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1572492694-6520-8-git-send-email-zohar@linux.ibm.com
2019-11-12 12:25:50 +11:00
Nayna Jain e14555e3d0 ima: Make process_buffer_measurement() generic
process_buffer_measurement() is limited to measuring the kexec boot
command line. This patch makes process_buffer_measurement() more
generic, allowing it to measure other types of buffer data (e.g.
blacklisted binary hashes or key hashes).

process_buffer_measurement() may be called directly from an IMA hook
or as an auxiliary measurement record. In both cases the buffer
measurement is based on policy. This patch modifies the function to
conditionally retrieve the policy defined PCR and template for the IMA
hook case.

Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
[zohar@linux.ibm.com: added comment in process_buffer_measurement()]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1572492694-6520-6-git-send-email-zohar@linux.ibm.com
2019-11-12 12:25:50 +11:00
Masahiro Yamada 7a8beb7ad5 integrity: remove pointless subdir-$(CONFIG_...)
The ima/ and evm/ sub-directories contain built-in objects, so
obj-$(CONFIG_...) is the correct way to descend into them.

subdir-$(CONFIG_...) is redundant.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-10-05 15:29:49 +09:00
Masahiro Yamada 6b190d3ce0 integrity: remove unneeded, broken attempt to add -fshort-wchar
I guess commit 15ea0e1e3e ("efi: Import certificates from UEFI Secure
Boot") attempted to add -fshort-wchar for building load_uefi.o, but it
has never worked as intended.

load_uefi.o is created in the platform_certs/ sub-directory. If you
really want to add -fshort-wchar, the correct code is:

  $(obj)/platform_certs/load_uefi.o: KBUILD_CFLAGS += -fshort-wchar

But, you do not need to fix it.

Commit 8c97023cf0 ("Kbuild: use -fshort-wchar globally") had already
added -fshort-wchar globally. This code was unneeded in the first place.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-10-05 15:29:49 +09:00
Linus Torvalds aefcf2f4b5 Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull kernel lockdown mode from James Morris:
 "This is the latest iteration of the kernel lockdown patchset, from
  Matthew Garrett, David Howells and others.

  From the original description:

    This patchset introduces an optional kernel lockdown feature,
    intended to strengthen the boundary between UID 0 and the kernel.
    When enabled, various pieces of kernel functionality are restricted.
    Applications that rely on low-level access to either hardware or the
    kernel may cease working as a result - therefore this should not be
    enabled without appropriate evaluation beforehand.

    The majority of mainstream distributions have been carrying variants
    of this patchset for many years now, so there's value in providing a
    doesn't meet every distribution requirement, but gets us much closer
    to not requiring external patches.

  There are two major changes since this was last proposed for mainline:

   - Separating lockdown from EFI secure boot. Background discussion is
     covered here: https://lwn.net/Articles/751061/

   -  Implementation as an LSM, with a default stackable lockdown LSM
      module. This allows the lockdown feature to be policy-driven,
      rather than encoding an implicit policy within the mechanism.

  The new locked_down LSM hook is provided to allow LSMs to make a
  policy decision around whether kernel functionality that would allow
  tampering with or examining the runtime state of the kernel should be
  permitted.

  The included lockdown LSM provides an implementation with a simple
  policy intended for general purpose use. This policy provides a coarse
  level of granularity, controllable via the kernel command line:

    lockdown={integrity|confidentiality}

  Enable the kernel lockdown feature. If set to integrity, kernel features
  that allow userland to modify the running kernel are disabled. If set to
  confidentiality, kernel features that allow userland to extract
  confidential information from the kernel are also disabled.

  This may also be controlled via /sys/kernel/security/lockdown and
  overriden by kernel configuration.

  New or existing LSMs may implement finer-grained controls of the
  lockdown features. Refer to the lockdown_reason documentation in
  include/linux/security.h for details.

  The lockdown feature has had signficant design feedback and review
  across many subsystems. This code has been in linux-next for some
  weeks, with a few fixes applied along the way.

  Stephen Rothwell noted that commit 9d1f8be5cf ("bpf: Restrict bpf
  when kernel lockdown is in confidentiality mode") is missing a
  Signed-off-by from its author. Matthew responded that he is providing
  this under category (c) of the DCO"

* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
  kexec: Fix file verification on S390
  security: constify some arrays in lockdown LSM
  lockdown: Print current->comm in restriction messages
  efi: Restrict efivar_ssdt_load when the kernel is locked down
  tracefs: Restrict tracefs when the kernel is locked down
  debugfs: Restrict debugfs when the kernel is locked down
  kexec: Allow kexec_file() with appropriate IMA policy when locked down
  lockdown: Lock down perf when in confidentiality mode
  bpf: Restrict bpf when kernel lockdown is in confidentiality mode
  lockdown: Lock down tracing and perf kprobes when in confidentiality mode
  lockdown: Lock down /proc/kcore
  x86/mmiotrace: Lock down the testmmiotrace module
  lockdown: Lock down module params that specify hardware parameters (eg. ioport)
  lockdown: Lock down TIOCSSERIAL
  lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
  acpi: Disable ACPI table override if the kernel is locked down
  acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
  ACPI: Limit access to custom_method when the kernel is locked down
  x86/msr: Restrict MSR access when the kernel is locked down
  x86: Lock down IO port access when the kernel is locked down
  ...
2019-09-28 08:14:15 -07:00
Gustavo A. R. Silva 2a7f0e53da ima: ima_api: Use struct_size() in kzalloc()
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct ima_template_entry {
	...
        struct ima_field_data template_data[0]; /* template related data */
};

instance = kzalloc(sizeof(struct ima_template_entry) + count * sizeof(struct ima_field_data), GFP_NOFS);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kzalloc(struct_size(instance, entry, count), GFP_NOFS);

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-29 14:23:30 -04:00
Gustavo A. R. Silva fa5b571753 ima: use struct_size() in kzalloc()
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
   int stuff;
   struct boo entry[];
};

instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-29 14:23:22 -04:00
Thiago Jung Bauermann 556d971bda ima: Fix use after free in ima_read_modsig()
If we can't parse the PKCS7 in the appended modsig, we will free the modsig
structure and then access one of its members to determine the error value.

Fixes: 39b0709636 ("ima: Implement support for module-style appended signatures")
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-28 15:01:24 -04:00
Matthew Garrett 29d3c1c8df kexec: Allow kexec_file() with appropriate IMA policy when locked down
Systems in lockdown mode should block the kexec of untrusted kernels.
For x86 and ARM we can ensure that a kernel is trustworthy by validating
a PE signature, but this isn't possible on other architectures. On those
platforms we can use IMA digital signatures instead. Add a function to
determine whether IMA has or will verify signatures for a given event type,
and if so permit kexec_file() even if the kernel is otherwise locked down.
This is restricted to cases where CONFIG_INTEGRITY_TRUSTED_KEYRING is set
in order to prevent an attacker from loading additional keys at runtime.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Mimi Zohar <zohar@linux.ibm.com>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: linux-integrity@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
Jiri Bohac 99d5cadfde kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE
This is a preparatory patch for kexec_file_load() lockdown.  A locked down
kernel needs to prevent unsigned kernel images from being loaded with
kexec_file_load().  Currently, the only way to force the signature
verification is compiling with KEXEC_VERIFY_SIG.  This prevents loading
usigned images even when the kernel is not locked down at runtime.

This patch splits KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE.
Analogous to the MODULE_SIG and MODULE_SIG_FORCE for modules, KEXEC_SIG
turns on the signature verification but allows unsigned images to be
loaded.  KEXEC_SIG_FORCE disallows images without a valid signature.

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
cc: kexec@lists.infradead.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:15 -07:00
Sascha Hauer 4ece3125f2 ima: fix freeing ongoing ahash_request
integrity_kernel_read() can fail in which case we forward to call
ahash_request_free() on a currently running request. We have to wait
for its completion before we can free the request.

This was observed by interrupting a "find / -type f -xdev -print0 | xargs -0
cat 1>/dev/null" with ctrl-c on an IMA enabled filesystem.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-05 18:40:28 -04:00
Sascha Hauer f5e1040196 ima: always return negative code for error
integrity_kernel_read() returns the number of bytes read. If this is
a short read then this positive value is returned from
ima_calc_file_hash_atfm(). Currently this is only indirectly called from
ima_calc_file_hash() and this function only tests for the return value
being zero or nonzero and also doesn't forward the return value.
Nevertheless there's no point in returning a positive value as an error,
so translate a short read into -EINVAL.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-05 18:40:27 -04:00
Thiago Jung Bauermann e5092255bb ima: Store the measurement again when appraising a modsig
If the IMA template contains the "modsig" or "d-modsig" field, then the
modsig should be added to the measurement list when the file is appraised.

And that is what normally happens, but if a measurement rule caused a file
containing a modsig to be measured before a different rule causes it to be
appraised, the resulting measurement entry will not contain the modsig
because it is only fetched during appraisal. When the appraisal rule
triggers, it won't store a new measurement containing the modsig because
the file was already measured.

We need to detect that situation and store an additional measurement with
the modsig. This is done by adding an IMA_MEASURE action flag if we read a
modsig and the IMA template contains a modsig field.

Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-05 18:40:26 -04:00
Thiago Jung Bauermann 3878d505aa ima: Define ima-modsig template
Define new "d-modsig" template field which holds the digest that is
expected to match the one contained in the modsig, and also new "modsig"
template field which holds the appended file signature.

Add a new "ima-modsig" defined template descriptor with the new fields as
well as the ones from the "ima-sig" descriptor.

Change ima_store_measurement() to accept a struct modsig * argument so that
it can be passed along to the templates via struct ima_event_data.

Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-05 18:40:25 -04:00
Thiago Jung Bauermann 15588227e0 ima: Collect modsig
Obtain the modsig and calculate its corresponding hash in
ima_collect_measurement().

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-05 18:40:24 -04:00
Thiago Jung Bauermann 39b0709636 ima: Implement support for module-style appended signatures
Implement the appraise_type=imasig|modsig option, allowing IMA to read and
verify modsig signatures.

In case a file has both an xattr signature and an appended modsig, IMA will
only use the appended signature if the key used by the xattr signature
isn't present in the IMA or platform keyring.

Because modsig verification needs to convert from an integrity keyring id
to the keyring itself, add an integrity_keyring_from_id() function in
digsig.c so that integrity_modsig_verify() can use it.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-05 18:40:23 -04:00
Thiago Jung Bauermann a5fbeb615c ima: Factor xattr_verify() out of ima_appraise_measurement()
Verify xattr signature in a separate function so that the logic in
ima_appraise_measurement() remains clear when it gains the ability to also
verify an appended module signature.

The code in the switch statement is unchanged except for having to
dereference the status and cause variables (since they're now pointers),
and fixing the style of a block comment to appease checkpatch.

Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-05 18:40:22 -04:00
Thiago Jung Bauermann 9044d627fd ima: Add modsig appraise_type option for module-style appended signatures
Introduce the modsig keyword to the IMA policy syntax to specify that
a given hook should expect the file to have the IMA signature appended
to it. Here is how it can be used in a rule:

appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig

With this rule, IMA will accept either a signature stored in the extended
attribute or an appended signature.

For now, the rule above will behave exactly the same as if
appraise_type=imasig was specified. The actual modsig implementation
will be introduced separately.

Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-05 18:40:21 -04:00
Thiago Jung Bauermann cf38fed1e1 integrity: Select CONFIG_KEYS instead of depending on it
This avoids a dependency cycle in soon-to-be-introduced
CONFIG_IMA_APPRAISE_MODSIG: it will select CONFIG_MODULE_SIG_FORMAT
which in turn selects CONFIG_KEYS. Kconfig then complains that
CONFIG_INTEGRITY_SIGNATURE depends on CONFIG_KEYS.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-05 18:40:20 -04:00
Mimi Zohar b36f281f4a ima: initialize the "template" field with the default template
IMA policy rules are walked sequentially.  Depending on the ordering of
the policy rules, the "template" field might be defined in one rule, but
will be replaced by subsequent, applicable rules, even if the rule does
not explicitly define the "template" field.

This patch initializes the "template" once and only replaces the
"template", when explicitly defined.

Fixes: 19453ce0bc ("IMA: support for per policy rule template formats")
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-01 08:25:36 -04:00
Linus Torvalds 028db3e290 Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs"
This reverts merge 0f75ef6a9c (and thus
effectively commits

   7a1ade8475 ("keys: Provide KEYCTL_GRANT_PERMISSION")
   2e12256b9a ("keys: Replace uid/gid/perm permissions checking with an ACL")

that the merge brought in).

It turns out that it breaks booting with an encrypted volume, and Eric
biggers reports that it also breaks the fscrypt tests [1] and loading of
in-kernel X.509 certificates [2].

The root cause of all the breakage is likely the same, but David Howells
is off email so rather than try to work it out it's getting reverted in
order to not impact the rest of the merge window.

 [1] https://lore.kernel.org/lkml/20190710011559.GA7973@sol.localdomain/
 [2] https://lore.kernel.org/lkml/20190710013225.GB7973@sol.localdomain/

Link: https://lore.kernel.org/lkml/CAHk-=wjxoeMJfeBahnWH=9zShKp2bsVy527vo3_y8HfOdhwAAw@mail.gmail.com/
Reported-by: Eric Biggers <ebiggers@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-10 18:43:43 -07:00
Linus Torvalds 8b68150883 Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:
 "Bug fixes, code clean up, and new features:

   - IMA policy rules can be defined in terms of LSM labels, making the
     IMA policy dependent on LSM policy label changes, in particular LSM
     label deletions. The new environment, in which IMA-appraisal is
     being used, frequently updates the LSM policy and permits LSM label
     deletions.

   - Prevent an mmap'ed shared file opened for write from also being
     mmap'ed execute. In the long term, making this and other similar
     changes at the VFS layer would be preferable.

   - The IMA per policy rule template format support is needed for a
     couple of new/proposed features (eg. kexec boot command line
     measurement, appended signatures, and VFS provided file hashes).

   - Other than the "boot-aggregate" record in the IMA measuremeent
     list, all other measurements are of file data. Measuring and
     storing the kexec boot command line in the IMA measurement list is
     the first buffer based measurement included in the measurement
     list"

* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  integrity: Introduce struct evm_xattr
  ima: Update MAX_TEMPLATE_NAME_LEN to fit largest reasonable definition
  KEXEC: Call ima_kexec_cmdline to measure the boot command line args
  IMA: Define a new template field buf
  IMA: Define a new hook to measure the kexec boot command line arguments
  IMA: support for per policy rule template formats
  integrity: Fix __integrity_init_keyring() section mismatch
  ima: Use designated initializers for struct ima_event_data
  ima: use the lsm policy update notifier
  LSM: switch to blocking policy update notifiers
  x86/ima: fix the Kconfig dependency for IMA_ARCH_POLICY
  ima: Make arch_policy_entry static
  ima: prevent a file already mmap'ed write to be mmap'ed execute
  x86/ima: check EFI SetupMode too
2019-07-08 20:28:59 -07:00
Linus Torvalds 0f75ef6a9c Keyrings ACL
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Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull keyring ACL support from David Howells:
 "This changes the permissions model used by keys and keyrings to be
  based on an internal ACL by the following means:

   - Replace the permissions mask internally with an ACL that contains a
     list of ACEs, each with a specific subject with a permissions mask.
     Potted default ACLs are available for new keys and keyrings.

     ACE subjects can be macroised to indicate the UID and GID specified
     on the key (which remain). Future commits will be able to add
     additional subject types, such as specific UIDs or domain
     tags/namespaces.

     Also split a number of permissions to give finer control. Examples
     include splitting the revocation permit from the change-attributes
     permit, thereby allowing someone to be granted permission to revoke
     a key without allowing them to change the owner; also the ability
     to join a keyring is split from the ability to link to it, thereby
     stopping a process accessing a keyring by joining it and thus
     acquiring use of possessor permits.

   - Provide a keyctl to allow the granting or denial of one or more
     permits to a specific subject. Direct access to the ACL is not
     granted, and the ACL cannot be viewed"

* tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  keys: Provide KEYCTL_GRANT_PERMISSION
  keys: Replace uid/gid/perm permissions checking with an ACL
2019-07-08 19:56:57 -07:00
Linus Torvalds c84ca912b0 Keyrings namespacing
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Merge tag 'keys-namespace-20190627' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull keyring namespacing from David Howells:
 "These patches help make keys and keyrings more namespace aware.

  Firstly some miscellaneous patches to make the process easier:

   - Simplify key index_key handling so that the word-sized chunks
     assoc_array requires don't have to be shifted about, making it
     easier to add more bits into the key.

   - Cache the hash value in the key so that we don't have to calculate
     on every key we examine during a search (it involves a bunch of
     multiplications).

   - Allow keying_search() to search non-recursively.

  Then the main patches:

   - Make it so that keyring names are per-user_namespace from the point
     of view of KEYCTL_JOIN_SESSION_KEYRING so that they're not
     accessible cross-user_namespace.

     keyctl_capabilities() shows KEYCTL_CAPS1_NS_KEYRING_NAME for this.

   - Move the user and user-session keyrings to the user_namespace
     rather than the user_struct. This prevents them propagating
     directly across user_namespaces boundaries (ie. the KEY_SPEC_*
     flags will only pick from the current user_namespace).

   - Make it possible to include the target namespace in which the key
     shall operate in the index_key. This will allow the possibility of
     multiple keys with the same description, but different target
     domains to be held in the same keyring.

     keyctl_capabilities() shows KEYCTL_CAPS1_NS_KEY_TAG for this.

   - Make it so that keys are implicitly invalidated by removal of a
     domain tag, causing them to be garbage collected.

   - Institute a network namespace domain tag that allows keys to be
     differentiated by the network namespace in which they operate. New
     keys that are of a type marked 'KEY_TYPE_NET_DOMAIN' are assigned
     the network domain in force when they are created.

   - Make it so that the desired network namespace can be handed down
     into the request_key() mechanism. This allows AFS, NFS, etc. to
     request keys specific to the network namespace of the superblock.

     This also means that the keys in the DNS record cache are
     thenceforth namespaced, provided network filesystems pass the
     appropriate network namespace down into dns_query().

     For DNS, AFS and NFS are good, whilst CIFS and Ceph are not. Other
     cache keyrings, such as idmapper keyrings, also need to set the
     domain tag - for which they need access to the network namespace of
     the superblock"

* tag 'keys-namespace-20190627' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  keys: Pass the network namespace into request_key mechanism
  keys: Network namespace domain tag
  keys: Garbage collect keys for which the domain has been removed
  keys: Include target namespace in match criteria
  keys: Move the user and user-session keyrings to the user_namespace
  keys: Namespace keyring names
  keys: Add a 'recurse' flag for keyring searches
  keys: Cache the hash value to avoid lots of recalculation
  keys: Simplify key description management
2019-07-08 19:36:47 -07:00
Thiago Jung Bauermann 650b29dbdf integrity: Introduce struct evm_xattr
Even though struct evm_ima_xattr_data includes a fixed-size array to hold a
SHA1 digest, most of the code ignores the array and uses the struct to mean
"type indicator followed by data of unspecified size" and tracks the real
size of what the struct represents in a separate length variable.

The only exception to that is the EVM code, which correctly uses the
definition of struct evm_ima_xattr_data.

So make this explicit in the code by removing the length specification from
the array in struct evm_ima_xattr_data. Also, change the name of the
element from digest to data since in most places the array doesn't hold a
digest.

A separate struct evm_xattr is introduced, with the original definition of
evm_ima_xattr_data to be used in the places that actually expect that
definition, specifically the EVM HMAC code.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-06-30 17:54:41 -04:00
Thiago Jung Bauermann 337619eb44 ima: Update MAX_TEMPLATE_NAME_LEN to fit largest reasonable definition
MAX_TEMPLATE_NAME_LEN is used when restoring measurements carried over from
a kexec. It should be set to the length of a template containing all fields
except for 'd' and 'n', which don't need to be accounted for since they
shouldn't be defined in the same template description as 'd-ng' and 'n-ng'.

That length is greater than the current 15, so update using a sizeof() to
show where the number comes from and also can be visually shown to be
correct. The sizeof() is calculated at compile time.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-06-30 17:54:40 -04:00
Prakhar Srivastava 86b4da8c0e IMA: Define a new template field buf
A buffer(kexec boot command line arguments) measured into IMA
measuremnt list cannot be appraised, without already being
aware of the buffer contents. Since hashes are non-reversible,
raw buffer is needed for validation or regenerating hash for
appraisal/attestation.

Add support to store/read the buffer contents in HEX.
The kexec cmdline hash is stored in the "d-ng" field of the
template data.  It can be verified using
sudo cat /sys/kernel/security/integrity/ima/ascii_runtime_measurements |
  grep  kexec-cmdline | cut -d' ' -f 6 | xxd -r -p | sha256sum

- Add two new fields to ima_event_data to hold the buf and
buf_len
- Add a new template field 'buf' to be used to store/read
the buffer data.
- Updated process_buffer_meaurement to add the buffer to
ima_event_data. process_buffer_measurement added in
"Define a new IMA hook to measure the boot command line
 arguments"
- Add a new template policy name ima-buf to represent
'd-ng|n-ng|buf'

Signed-off-by: Prakhar Srivastava <prsriva02@gmail.com>
Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-06-30 17:53:45 -04:00
David Howells 2e12256b9a keys: Replace uid/gid/perm permissions checking with an ACL
Replace the uid/gid/perm permissions checking on a key with an ACL to allow
the SETATTR and SEARCH permissions to be split.  This will also allow a
greater range of subjects to represented.

============
WHY DO THIS?
============

The problem is that SETATTR and SEARCH cover a slew of actions, not all of
which should be grouped together.

For SETATTR, this includes actions that are about controlling access to a
key:

 (1) Changing a key's ownership.

 (2) Changing a key's security information.

 (3) Setting a keyring's restriction.

And actions that are about managing a key's lifetime:

 (4) Setting an expiry time.

 (5) Revoking a key.

and (proposed) managing a key as part of a cache:

 (6) Invalidating a key.

Managing a key's lifetime doesn't really have anything to do with
controlling access to that key.

Expiry time is awkward since it's more about the lifetime of the content
and so, in some ways goes better with WRITE permission.  It can, however,
be set unconditionally by a process with an appropriate authorisation token
for instantiating a key, and can also be set by the key type driver when a
key is instantiated, so lumping it with the access-controlling actions is
probably okay.

As for SEARCH permission, that currently covers:

 (1) Finding keys in a keyring tree during a search.

 (2) Permitting keyrings to be joined.

 (3) Invalidation.

But these don't really belong together either, since these actions really
need to be controlled separately.

Finally, there are number of special cases to do with granting the
administrator special rights to invalidate or clear keys that I would like
to handle with the ACL rather than key flags and special checks.


===============
WHAT IS CHANGED
===============

The SETATTR permission is split to create two new permissions:

 (1) SET_SECURITY - which allows the key's owner, group and ACL to be
     changed and a restriction to be placed on a keyring.

 (2) REVOKE - which allows a key to be revoked.

The SEARCH permission is split to create:

 (1) SEARCH - which allows a keyring to be search and a key to be found.

 (2) JOIN - which allows a keyring to be joined as a session keyring.

 (3) INVAL - which allows a key to be invalidated.

The WRITE permission is also split to create:

 (1) WRITE - which allows a key's content to be altered and links to be
     added, removed and replaced in a keyring.

 (2) CLEAR - which allows a keyring to be cleared completely.  This is
     split out to make it possible to give just this to an administrator.

 (3) REVOKE - see above.


Keys acquire ACLs which consist of a series of ACEs, and all that apply are
unioned together.  An ACE specifies a subject, such as:

 (*) Possessor - permitted to anyone who 'possesses' a key
 (*) Owner - permitted to the key owner
 (*) Group - permitted to the key group
 (*) Everyone - permitted to everyone

Note that 'Other' has been replaced with 'Everyone' on the assumption that
you wouldn't grant a permit to 'Other' that you wouldn't also grant to
everyone else.

Further subjects may be made available by later patches.

The ACE also specifies a permissions mask.  The set of permissions is now:

	VIEW		Can view the key metadata
	READ		Can read the key content
	WRITE		Can update/modify the key content
	SEARCH		Can find the key by searching/requesting
	LINK		Can make a link to the key
	SET_SECURITY	Can change owner, ACL, expiry
	INVAL		Can invalidate
	REVOKE		Can revoke
	JOIN		Can join this keyring
	CLEAR		Can clear this keyring


The KEYCTL_SETPERM function is then deprecated.

The KEYCTL_SET_TIMEOUT function then is permitted if SET_SECURITY is set,
or if the caller has a valid instantiation auth token.

The KEYCTL_INVALIDATE function then requires INVAL.

The KEYCTL_REVOKE function then requires REVOKE.

The KEYCTL_JOIN_SESSION_KEYRING function then requires JOIN to join an
existing keyring.

The JOIN permission is enabled by default for session keyrings and manually
created keyrings only.


======================
BACKWARD COMPATIBILITY
======================

To maintain backward compatibility, KEYCTL_SETPERM will translate the
permissions mask it is given into a new ACL for a key - unless
KEYCTL_SET_ACL has been called on that key, in which case an error will be
returned.

It will convert possessor, owner, group and other permissions into separate
ACEs, if each portion of the mask is non-zero.

SETATTR permission turns on all of INVAL, REVOKE and SET_SECURITY.  WRITE
permission turns on WRITE, REVOKE and, if a keyring, CLEAR.  JOIN is turned
on if a keyring is being altered.

The KEYCTL_DESCRIBE function translates the ACL back into a permissions
mask to return depending on possessor, owner, group and everyone ACEs.

It will make the following mappings:

 (1) INVAL, JOIN -> SEARCH

 (2) SET_SECURITY -> SETATTR

 (3) REVOKE -> WRITE if SETATTR isn't already set

 (4) CLEAR -> WRITE

Note that the value subsequently returned by KEYCTL_DESCRIBE may not match
the value set with KEYCTL_SETATTR.


=======
TESTING
=======

This passes the keyutils testsuite for all but a couple of tests:

 (1) tests/keyctl/dh_compute/badargs: The first wrong-key-type test now
     returns EOPNOTSUPP rather than ENOKEY as READ permission isn't removed
     if the type doesn't have ->read().  You still can't actually read the
     key.

 (2) tests/keyctl/permitting/valid: The view-other-permissions test doesn't
     work as Other has been replaced with Everyone in the ACL.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-27 23:03:07 +01:00
David Howells dcf49dbc80 keys: Add a 'recurse' flag for keyring searches
Add a 'recurse' flag for keyring searches so that the flag can be omitted
and recursion disabled, thereby allowing just the nominated keyring to be
searched and none of the children.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-26 21:02:32 +01:00
Prakhar Srivastava b0935123a1 IMA: Define a new hook to measure the kexec boot command line arguments
Currently during soft reboot(kexec_file_load) boot command line
arguments are not measured. Define hooks needed to measure kexec
command line arguments during soft reboot(kexec_file_load).

- A new ima hook ima_kexec_cmdline is defined to be called by the
kexec code.
- A new function process_buffer_measurement is defined to measure
the buffer hash into the IMA measurement list.
- A new func policy KEXEC_CMDLINE is defined to control the
 measurement.

Signed-off-by: Prakhar Srivastava <prsriva02@gmail.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-06-24 08:29:57 -04:00
Matthew Garrett 19453ce0bc IMA: support for per policy rule template formats
Admins may wish to log different measurements using different IMA
templates. Add support for overriding the default template on a per-rule
basis.

Inspired-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-06-19 18:51:01 -04:00
Geert Uytterhoeven 8c655784e2 integrity: Fix __integrity_init_keyring() section mismatch
With gcc-4.6.3:

    WARNING: vmlinux.o(.text.unlikely+0x24c64): Section mismatch in reference from the function __integrity_init_keyring() to the function .init.text:set_platform_trusted_keys()
    The function __integrity_init_keyring() references
    the function __init set_platform_trusted_keys().
    This is often because __integrity_init_keyring lacks a __init
    annotation or the annotation of set_platform_trusted_keys is wrong.

Indeed, if the compiler decides not to inline __integrity_init_keyring(),
a warning is issued.

Fix this by adding the missing __init annotation.

Fixes: 9dc92c4517 ("integrity: Define a trusted platform keyring")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Nayna Jain <nayna@linux.ibm.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-06-17 14:13:20 -04:00
Thiago Jung Bauermann e038f5f691 ima: Use designated initializers for struct ima_event_data
Designated initializers allow specifying only the members of the struct
that need initialization. Non-mentioned members are initialized to zero.

This makes the code a bit clearer (particularly in ima_add_boot_aggregate)
and also allows adding a new member to the struct without having to update
all struct initializations.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-06-14 09:02:44 -04:00
Janne Karhunen b169424551 ima: use the lsm policy update notifier
Don't do lazy policy updates while running the rule matching,
run the updates as they happen.

Depends on commit f242064c5df3 ("LSM: switch to blocking policy update notifiers")

Signed-off-by: Janne Karhunen <janne.karhunen@gmail.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-06-14 09:02:43 -04:00
Nayna Jain 9e1e5d4372 x86/ima: fix the Kconfig dependency for IMA_ARCH_POLICY
If enabled, ima arch specific policies always adds the measurements rules,
this makes it dependent on CONFIG_IMA. CONFIG_IMA_APPRAISE implicitly takes
care of this, however it is needed explicitly for CONFIG_KEXEC_VERIFY_SIG.

This patch adds the CONFIG_IMA dependency in combination with
CONFIG_KEXEC_VERIFY_SIG for CONFIG_IMA_ARCH_POLICY

Fixes: d958083a8f (x86/ima: define arch_get_ima_policy() for x86)
Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-06-14 08:53:58 -04:00
YueHaibing 68f2529078 ima: Make arch_policy_entry static
Fix sparse warning:

security/integrity/ima/ima_policy.c:202:23: warning:
 symbol 'arch_policy_entry' was not declared. Should it be static?

Fixes: 6191706246 ("ima: add support for arch specific policies")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Cc: stable@vger.kernel.org (linux-5.0)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-06-14 08:53:57 -04:00
Thomas Gleixner b886d83c5b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation version 2 of the license

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 315 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:17 +02:00
Mimi Zohar 2cd4737bc8 ima: prevent a file already mmap'ed write to be mmap'ed execute
The kernel calls deny_write_access() to prevent a file already opened
for write from being executed and also prevents files being executed
from being opened for write.  For some reason this does not extend to
files being mmap'ed execute.

From an IMA perspective, measuring/appraising the integrity of a file
being mmap'ed shared execute, without first making sure the file cannot
be modified, makes no sense.  This patch prevents files, in policy,
already mmap'ed shared write, from being mmap'ed execute.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-06-04 16:47:30 -04:00
Linus Torvalds d266b3f5ca Merge branch 'next-fixes-for-5.2-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity subsystem fixes from Mimi Zohar:
 "Four bug fixes, none 5.2-specific, all marked for stable.

  The first two are related to the architecture specific IMA policy
  support. The other two patches, one is related to EVM signatures,
  based on additional hash algorithms, and the other is related to
  displaying the IMA policy"

* 'next-fixes-for-5.2-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  ima: show rules with IMA_INMASK correctly
  evm: check hash algorithm passed to init_desc()
  ima: fix wrong signed policy requirement when not appraising
  x86/ima: Check EFI_RUNTIME_SERVICES before using
2019-05-31 11:08:44 -07:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Roberto Sassu 8cdc23a3d9 ima: show rules with IMA_INMASK correctly
Show the '^' character when a policy rule has flag IMA_INMASK.

Fixes: 80eae209d6 ("IMA: allow reading back the current IMA policy")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-05-29 23:18:25 -04:00
Roberto Sassu 221be106d7 evm: check hash algorithm passed to init_desc()
This patch prevents memory access beyond the evm_tfm array by checking the
validity of the index (hash algorithm) passed to init_desc(). The hash
algorithm can be arbitrarily set if the security.ima xattr type is not
EVM_XATTR_HMAC.

Fixes: 5feeb61183 ("evm: Allow non-SHA1 digital signatures")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-05-29 23:18:25 -04:00
Thomas Gleixner ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00