From 6f1a1d103b48b1533a9c804e7a069e2c8e937ce7 Mon Sep 17 00:00:00 2001
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: Wed, 25 Mar 2020 11:47:06 +0100
Subject: [PATCH 01/15] 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: 879b589210a9 ("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>
---
 security/integrity/ima/ima_crypto.c | 47 +++++++++++++++++++++++++----
 security/integrity/ima/ima_init.c   | 20 +++++++++---
 2 files changed, 57 insertions(+), 10 deletions(-)

diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index 423c84f95a14..8e445a671225 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -655,18 +655,29 @@ static void __init ima_pcrread(u32 idx, struct tpm_digest *d)
 }
 
 /*
- * Calculate the boot aggregate hash
+ * The boot_aggregate is a cumulative hash over TPM registers 0 - 7.  With
+ * TPM 1.2 the boot_aggregate was based on reading the SHA1 PCRs, but with
+ * TPM 2.0 hash agility, TPM chips could support multiple TPM PCR banks,
+ * allowing firmware to configure and enable different banks.
+ *
+ * Knowing which TPM bank is read to calculate the boot_aggregate digest
+ * needs to be conveyed to a verifier.  For this reason, use the same
+ * hash algorithm for reading the TPM PCRs as for calculating the boot
+ * aggregate digest as stored in the measurement list.
  */
-static int __init ima_calc_boot_aggregate_tfm(char *digest,
+static int __init ima_calc_boot_aggregate_tfm(char *digest, u16 alg_id,
 					      struct crypto_shash *tfm)
 {
-	struct tpm_digest d = { .alg_id = TPM_ALG_SHA1, .digest = {0} };
+	struct tpm_digest d = { .alg_id = alg_id, .digest = {0} };
 	int rc;
 	u32 i;
 	SHASH_DESC_ON_STACK(shash, tfm);
 
 	shash->tfm = tfm;
 
+	pr_devel("calculating the boot-aggregate based on TPM bank: %04x\n",
+		 d.alg_id);
+
 	rc = crypto_shash_init(shash);
 	if (rc != 0)
 		return rc;
@@ -675,7 +686,8 @@ static int __init ima_calc_boot_aggregate_tfm(char *digest,
 	for (i = TPM_PCR0; i < TPM_PCR8; i++) {
 		ima_pcrread(i, &d);
 		/* now accumulate with current aggregate */
-		rc = crypto_shash_update(shash, d.digest, TPM_DIGEST_SIZE);
+		rc = crypto_shash_update(shash, d.digest,
+					 crypto_shash_digestsize(tfm));
 	}
 	if (!rc)
 		crypto_shash_final(shash, digest);
@@ -685,14 +697,37 @@ static int __init ima_calc_boot_aggregate_tfm(char *digest,
 int __init ima_calc_boot_aggregate(struct ima_digest_data *hash)
 {
 	struct crypto_shash *tfm;
-	int rc;
+	u16 crypto_id, alg_id;
+	int rc, i, bank_idx = -1;
+
+	for (i = 0; i < ima_tpm_chip->nr_allocated_banks; i++) {
+		crypto_id = ima_tpm_chip->allocated_banks[i].crypto_id;
+		if (crypto_id == hash->algo) {
+			bank_idx = i;
+			break;
+		}
+
+		if (crypto_id == HASH_ALGO_SHA256)
+			bank_idx = i;
+
+		if (bank_idx == -1 && crypto_id == HASH_ALGO_SHA1)
+			bank_idx = i;
+	}
+
+	if (bank_idx == -1) {
+		pr_err("No suitable TPM algorithm for boot aggregate\n");
+		return 0;
+	}
+
+	hash->algo = ima_tpm_chip->allocated_banks[bank_idx].crypto_id;
 
 	tfm = ima_alloc_tfm(hash->algo);
 	if (IS_ERR(tfm))
 		return PTR_ERR(tfm);
 
 	hash->length = crypto_shash_digestsize(tfm);
-	rc = ima_calc_boot_aggregate_tfm(hash->digest, tfm);
+	alg_id = ima_tpm_chip->allocated_banks[bank_idx].alg_id;
+	rc = ima_calc_boot_aggregate_tfm(hash->digest, alg_id, tfm);
 
 	ima_free_tfm(tfm);
 
diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c
index 567468188a61..fc1e1002b48d 100644
--- a/security/integrity/ima/ima_init.c
+++ b/security/integrity/ima/ima_init.c
@@ -25,7 +25,7 @@ struct tpm_chip *ima_tpm_chip;
 /* Add the boot aggregate to the IMA measurement list and extend
  * the PCR register.
  *
- * Calculate the boot aggregate, a SHA1 over tpm registers 0-7,
+ * Calculate the boot aggregate, a hash over tpm registers 0-7,
  * assuming a TPM chip exists, and zeroes if the TPM chip does not
  * exist.  Add the boot aggregate measurement to the measurement
  * list and extend the PCR register.
@@ -49,15 +49,27 @@ static int __init ima_add_boot_aggregate(void)
 	int violation = 0;
 	struct {
 		struct ima_digest_data hdr;
-		char digest[TPM_DIGEST_SIZE];
+		char digest[TPM_MAX_DIGEST_SIZE];
 	} hash;
 
 	memset(iint, 0, sizeof(*iint));
 	memset(&hash, 0, sizeof(hash));
 	iint->ima_hash = &hash.hdr;
-	iint->ima_hash->algo = HASH_ALGO_SHA1;
-	iint->ima_hash->length = SHA1_DIGEST_SIZE;
+	iint->ima_hash->algo = ima_hash_algo;
+	iint->ima_hash->length = hash_digest_size[ima_hash_algo];
 
+	/*
+	 * With TPM 2.0 hash agility, TPM chips could support multiple TPM
+	 * PCR banks, allowing firmware to configure and enable different
+	 * banks.  The SHA1 bank is not necessarily enabled.
+	 *
+	 * Use the same hash algorithm for reading the TPM PCRs as for
+	 * calculating the boot aggregate digest.  Preference is given to
+	 * the configured IMA default hash algorithm.  Otherwise, use the
+	 * TCG required banks - SHA256 for TPM 2.0, SHA1 for TPM 1.2.
+	 * Ultimately select SHA1 also for TPM 2.0 if the SHA256 PCR bank
+	 * is not found.
+	 */
 	if (ima_tpm_chip) {
 		result = ima_calc_boot_aggregate(&hash.hdr);
 		if (result < 0) {

From e144d6b265415ddbdc54b3f17f4f95133effa5a8 Mon Sep 17 00:00:00 2001
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: Wed, 25 Mar 2020 11:47:07 +0100
Subject: [PATCH 02/15] 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: b16942455193 ("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>
---
 security/integrity/ima/ima_main.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 9d0abedeae77..f96f151294e6 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -792,6 +792,9 @@ static int __init init_ima(void)
 		error = ima_init();
 	}
 
+	if (error)
+		return error;
+
 	error = register_blocking_lsm_notifier(&ima_lsm_policy_notifier);
 	if (error)
 		pr_warn("Couldn't register LSM notifier, error %d\n", error);

From 7ca79645a1f8837c3850b881a2c0b43cfba5dc36 Mon Sep 17 00:00:00 2001
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: Wed, 25 Mar 2020 11:47:08 +0100
Subject: [PATCH 03/15] 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>
---
 security/integrity/ima/ima.h        |  3 +--
 security/integrity/ima/ima_api.c    | 12 +-----------
 security/integrity/ima/ima_crypto.c | 18 +++++++-----------
 3 files changed, 9 insertions(+), 24 deletions(-)

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 64317d95363e..a2dfe24e04c7 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -138,8 +138,7 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash);
 int ima_calc_buffer_hash(const void *buf, loff_t len,
 			 struct ima_digest_data *hash);
 int ima_calc_field_array_hash(struct ima_field_data *field_data,
-			      struct ima_template_desc *desc, int num_fields,
-			      struct ima_digest_data *hash);
+			      struct ima_template_entry *entry);
 int __init ima_calc_boot_aggregate(struct ima_digest_data *hash);
 void ima_add_violation(struct file *file, const unsigned char *filename,
 		       struct integrity_iint_cache *iint,
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index f6bc00914aa5..2ef5a40c7ca5 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -96,26 +96,16 @@ int ima_store_template(struct ima_template_entry *entry,
 	static const char audit_cause[] = "hashing_error";
 	char *template_name = entry->template_desc->name;
 	int result;
-	struct {
-		struct ima_digest_data hdr;
-		char digest[TPM_DIGEST_SIZE];
-	} hash;
 
 	if (!violation) {
-		int num_fields = entry->template_desc->num_fields;
-
-		/* this function uses default algo */
-		hash.hdr.algo = HASH_ALGO_SHA1;
 		result = ima_calc_field_array_hash(&entry->template_data[0],
-						   entry->template_desc,
-						   num_fields, &hash.hdr);
+						   entry);
 		if (result < 0) {
 			integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode,
 					    template_name, op,
 					    audit_cause, result, 0);
 			return result;
 		}
-		memcpy(entry->digest, hash.hdr.digest, hash.hdr.length);
 	}
 	entry->pcr = pcr;
 	result = ima_add_template_entry(entry, violation, op, inode, filename);
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index 8e445a671225..03d73a4009ab 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -464,18 +464,16 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash)
  * Calculate the hash of template data
  */
 static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
-					 struct ima_template_desc *td,
-					 int num_fields,
-					 struct ima_digest_data *hash,
+					 struct ima_template_entry *entry,
 					 struct crypto_shash *tfm)
 {
 	SHASH_DESC_ON_STACK(shash, tfm);
+	struct ima_template_desc *td = entry->template_desc;
+	int num_fields = entry->template_desc->num_fields;
 	int rc, i;
 
 	shash->tfm = tfm;
 
-	hash->length = crypto_shash_digestsize(tfm);
-
 	rc = crypto_shash_init(shash);
 	if (rc != 0)
 		return rc;
@@ -504,24 +502,22 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
 	}
 
 	if (!rc)
-		rc = crypto_shash_final(shash, hash->digest);
+		rc = crypto_shash_final(shash, entry->digest);
 
 	return rc;
 }
 
 int ima_calc_field_array_hash(struct ima_field_data *field_data,
-			      struct ima_template_desc *desc, int num_fields,
-			      struct ima_digest_data *hash)
+			      struct ima_template_entry *entry)
 {
 	struct crypto_shash *tfm;
 	int rc;
 
-	tfm = ima_alloc_tfm(hash->algo);
+	tfm = ima_alloc_tfm(HASH_ALGO_SHA1);
 	if (IS_ERR(tfm))
 		return PTR_ERR(tfm);
 
-	rc = ima_calc_field_array_hash_tfm(field_data, desc, num_fields,
-					   hash, tfm);
+	rc = ima_calc_field_array_hash_tfm(field_data, entry, tfm);
 
 	ima_free_tfm(tfm);
 

From aa724fe18a8a8285d0071c3bfc932efb090d142d Mon Sep 17 00:00:00 2001
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: Wed, 25 Mar 2020 11:47:09 +0100
Subject: [PATCH 04/15] 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>
---
 security/integrity/ima/ima.h          |  6 +++++-
 security/integrity/ima/ima_api.c      | 10 ++++++++++
 security/integrity/ima/ima_crypto.c   | 10 +++++++++-
 security/integrity/ima/ima_fs.c       |  4 ++--
 security/integrity/ima/ima_queue.c    | 10 ++++++----
 security/integrity/ima/ima_template.c | 15 +++++++++++++--
 6 files changed, 45 insertions(+), 10 deletions(-)

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index a2dfe24e04c7..2a7ed68e6414 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -45,11 +45,15 @@ enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
 #define IMA_TEMPLATE_IMA_NAME "ima"
 #define IMA_TEMPLATE_IMA_FMT "d|n"
 
+#define NR_BANKS(chip) ((chip != NULL) ? chip->nr_allocated_banks : 0)
+
 /* current content of the policy */
 extern int ima_policy_flag;
 
 /* set during initialization */
 extern int ima_hash_algo;
+extern int ima_sha1_idx __ro_after_init;
+extern int ima_extra_slots __ro_after_init;
 extern int ima_appraise;
 extern struct tpm_chip *ima_tpm_chip;
 
@@ -92,7 +96,7 @@ struct ima_template_desc {
 
 struct ima_template_entry {
 	int pcr;
-	u8 digest[TPM_DIGEST_SIZE];	/* sha1 or md5 measurement hash */
+	struct tpm_digest *digests;
 	struct ima_template_desc *template_desc; /* template descriptor */
 	u32 template_data_len;
 	struct ima_field_data template_data[0];	/* template related data */
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 2ef5a40c7ca5..78e0b0a7723e 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -27,6 +27,7 @@ void ima_free_template_entry(struct ima_template_entry *entry)
 	for (i = 0; i < entry->template_desc->num_fields; i++)
 		kfree(entry->template_data[i].data);
 
+	kfree(entry->digests);
 	kfree(entry);
 }
 
@@ -38,6 +39,7 @@ int ima_alloc_init_template(struct ima_event_data *event_data,
 			    struct ima_template_desc *desc)
 {
 	struct ima_template_desc *template_desc;
+	struct tpm_digest *digests;
 	int i, result = 0;
 
 	if (desc)
@@ -50,6 +52,14 @@ int ima_alloc_init_template(struct ima_event_data *event_data,
 	if (!*entry)
 		return -ENOMEM;
 
+	digests = kcalloc(NR_BANKS(ima_tpm_chip) + ima_extra_slots,
+			  sizeof(*digests), GFP_NOFS);
+	if (!digests) {
+		result = -ENOMEM;
+		goto out;
+	}
+
+	(*entry)->digests = digests;
 	(*entry)->template_desc = template_desc;
 	for (i = 0; i < template_desc->num_fields; i++) {
 		const struct ima_template_field *field =
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index 03d73a4009ab..fe02eb28b32b 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -57,6 +57,13 @@ MODULE_PARM_DESC(ahash_bufsize, "Maximum ahash buffer size");
 static struct crypto_shash *ima_shash_tfm;
 static struct crypto_ahash *ima_ahash_tfm;
 
+int ima_sha1_idx __ro_after_init;
+/*
+ * Additional number of slots reserved, as needed, for SHA1
+ * and IMA default algo.
+ */
+int ima_extra_slots __ro_after_init = 1;
+
 int __init ima_init_crypto(void)
 {
 	long rc;
@@ -502,7 +509,8 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
 	}
 
 	if (!rc)
-		rc = crypto_shash_final(shash, entry->digest);
+		rc = crypto_shash_final(shash,
+					entry->digests[ima_sha1_idx].digest);
 
 	return rc;
 }
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index a71e822a6e92..8b030a1c5e0d 100644
--- a/security/integrity/ima/ima_fs.c
+++ b/security/integrity/ima/ima_fs.c
@@ -150,7 +150,7 @@ int ima_measurements_show(struct seq_file *m, void *v)
 	ima_putc(m, &pcr, sizeof(e->pcr));
 
 	/* 2nd: template digest */
-	ima_putc(m, e->digest, TPM_DIGEST_SIZE);
+	ima_putc(m, e->digests[ima_sha1_idx].digest, TPM_DIGEST_SIZE);
 
 	/* 3rd: template name size */
 	namelen = !ima_canonical_fmt ? strlen(template_name) :
@@ -233,7 +233,7 @@ static int ima_ascii_measurements_show(struct seq_file *m, void *v)
 	seq_printf(m, "%2d ", e->pcr);
 
 	/* 2nd: SHA1 template hash */
-	ima_print_digest(m, e->digest, TPM_DIGEST_SIZE);
+	ima_print_digest(m, e->digests[ima_sha1_idx].digest, TPM_DIGEST_SIZE);
 
 	/* 3th:  template name */
 	seq_printf(m, " %s", template_name);
diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c
index 8753212ddb18..49db71c200b4 100644
--- a/security/integrity/ima/ima_queue.c
+++ b/security/integrity/ima/ima_queue.c
@@ -55,7 +55,8 @@ static struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest_value,
 	key = ima_hash_key(digest_value);
 	rcu_read_lock();
 	hlist_for_each_entry_rcu(qe, &ima_htable.queue[key], hnext) {
-		rc = memcmp(qe->entry->digest, digest_value, TPM_DIGEST_SIZE);
+		rc = memcmp(qe->entry->digests[ima_sha1_idx].digest,
+			    digest_value, TPM_DIGEST_SIZE);
 		if ((rc == 0) && (qe->entry->pcr == pcr)) {
 			ret = qe;
 			break;
@@ -75,7 +76,7 @@ static int get_binary_runtime_size(struct ima_template_entry *entry)
 	int size = 0;
 
 	size += sizeof(u32);	/* pcr */
-	size += sizeof(entry->digest);
+	size += TPM_DIGEST_SIZE;
 	size += sizeof(int);	/* template name size field */
 	size += strlen(entry->template_desc->name);
 	size += sizeof(entry->template_data_len);
@@ -107,7 +108,7 @@ static int ima_add_digest_entry(struct ima_template_entry *entry,
 
 	atomic_long_inc(&ima_htable.len);
 	if (update_htable) {
-		key = ima_hash_key(entry->digest);
+		key = ima_hash_key(entry->digests[ima_sha1_idx].digest);
 		hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);
 	}
 
@@ -171,7 +172,8 @@ int ima_add_template_entry(struct ima_template_entry *entry, int violation,
 
 	mutex_lock(&ima_extend_list_mutex);
 	if (!violation) {
-		memcpy(digest, entry->digest, sizeof(digest));
+		memcpy(digest, entry->digests[ima_sha1_idx].digest,
+		       sizeof(digest));
 		if (ima_lookup_digest_entry(digest, entry->pcr)) {
 			audit_cause = "hash_exists";
 			result = -EEXIST;
diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c
index 062d9ad49afb..de84252e65e9 100644
--- a/security/integrity/ima/ima_template.c
+++ b/security/integrity/ima/ima_template.c
@@ -301,6 +301,7 @@ static int ima_restore_template_data(struct ima_template_desc *template_desc,
 				     int template_data_size,
 				     struct ima_template_entry **entry)
 {
+	struct tpm_digest *digests;
 	int ret = 0;
 	int i;
 
@@ -309,11 +310,21 @@ static int ima_restore_template_data(struct ima_template_desc *template_desc,
 	if (!*entry)
 		return -ENOMEM;
 
+	digests = kcalloc(NR_BANKS(ima_tpm_chip) + ima_extra_slots,
+			  sizeof(*digests), GFP_NOFS);
+	if (!digests) {
+		kfree(*entry);
+		return -ENOMEM;
+	}
+
+	(*entry)->digests = digests;
+
 	ret = ima_parse_buf(template_data, template_data + template_data_size,
 			    NULL, template_desc->num_fields,
 			    (*entry)->template_data, NULL, NULL,
 			    ENFORCE_FIELDS | ENFORCE_BUFEND, "template data");
 	if (ret < 0) {
+		kfree((*entry)->digests);
 		kfree(*entry);
 		return ret;
 	}
@@ -445,8 +456,8 @@ int ima_restore_measurement_list(loff_t size, void *buf)
 		if (ret < 0)
 			break;
 
-		memcpy(entry->digest, hdr[HDR_DIGEST].data,
-		       hdr[HDR_DIGEST].len);
+		memcpy(entry->digests[ima_sha1_idx].digest,
+		       hdr[HDR_DIGEST].data, hdr[HDR_DIGEST].len);
 		entry->pcr = !ima_canonical_fmt ? *(hdr[HDR_PCR].data) :
 			     le32_to_cpu(*(hdr[HDR_PCR].data));
 		ret = ima_restore_measurement_entry(entry);

From 6d94809af6b0830c4dfcad661535a5939bcb8a7d Mon Sep 17 00:00:00 2001
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: Wed, 25 Mar 2020 11:52:48 +0100
Subject: [PATCH 05/15] 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>
---
 security/integrity/ima/ima_crypto.c | 145 +++++++++++++++++++++++-----
 1 file changed, 119 insertions(+), 26 deletions(-)

diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index fe02eb28b32b..ab1c05ad1314 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -57,14 +57,21 @@ MODULE_PARM_DESC(ahash_bufsize, "Maximum ahash buffer size");
 static struct crypto_shash *ima_shash_tfm;
 static struct crypto_ahash *ima_ahash_tfm;
 
+struct ima_algo_desc {
+	struct crypto_shash *tfm;
+	enum hash_algo algo;
+};
+
 int ima_sha1_idx __ro_after_init;
 /*
  * Additional number of slots reserved, as needed, for SHA1
  * and IMA default algo.
  */
-int ima_extra_slots __ro_after_init = 1;
+int ima_extra_slots __ro_after_init;
 
-int __init ima_init_crypto(void)
+static struct ima_algo_desc *ima_algo_array;
+
+static int __init ima_init_ima_crypto(void)
 {
 	long rc;
 
@@ -83,26 +90,121 @@ int __init ima_init_crypto(void)
 static struct crypto_shash *ima_alloc_tfm(enum hash_algo algo)
 {
 	struct crypto_shash *tfm = ima_shash_tfm;
-	int rc;
+	int rc, i;
 
 	if (algo < 0 || algo >= HASH_ALGO__LAST)
 		algo = ima_hash_algo;
 
-	if (algo != ima_hash_algo) {
-		tfm = crypto_alloc_shash(hash_algo_name[algo], 0, 0);
-		if (IS_ERR(tfm)) {
-			rc = PTR_ERR(tfm);
-			pr_err("Can not allocate %s (reason: %d)\n",
-			       hash_algo_name[algo], rc);
-		}
+	if (algo == ima_hash_algo)
+		return tfm;
+
+	for (i = 0; i < NR_BANKS(ima_tpm_chip) + ima_extra_slots; i++)
+		if (ima_algo_array[i].tfm && ima_algo_array[i].algo == algo)
+			return ima_algo_array[i].tfm;
+
+	tfm = crypto_alloc_shash(hash_algo_name[algo], 0, 0);
+	if (IS_ERR(tfm)) {
+		rc = PTR_ERR(tfm);
+		pr_err("Can not allocate %s (reason: %d)\n",
+		       hash_algo_name[algo], rc);
 	}
 	return tfm;
 }
 
+int __init ima_init_crypto(void)
+{
+	enum hash_algo algo;
+	long rc;
+	int i;
+
+	rc = ima_init_ima_crypto();
+	if (rc)
+		return rc;
+
+	ima_sha1_idx = -1;
+
+	for (i = 0; i < NR_BANKS(ima_tpm_chip); i++) {
+		algo = ima_tpm_chip->allocated_banks[i].crypto_id;
+		if (algo == HASH_ALGO_SHA1)
+			ima_sha1_idx = i;
+	}
+
+	if (ima_sha1_idx < 0)
+		ima_sha1_idx = NR_BANKS(ima_tpm_chip) + ima_extra_slots++;
+
+	ima_algo_array = kcalloc(NR_BANKS(ima_tpm_chip) + ima_extra_slots,
+				 sizeof(*ima_algo_array), GFP_KERNEL);
+	if (!ima_algo_array) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	for (i = 0; i < NR_BANKS(ima_tpm_chip); i++) {
+		algo = ima_tpm_chip->allocated_banks[i].crypto_id;
+		ima_algo_array[i].algo = algo;
+
+		/* unknown TPM algorithm */
+		if (algo == HASH_ALGO__LAST)
+			continue;
+
+		if (algo == ima_hash_algo) {
+			ima_algo_array[i].tfm = ima_shash_tfm;
+			continue;
+		}
+
+		ima_algo_array[i].tfm = ima_alloc_tfm(algo);
+		if (IS_ERR(ima_algo_array[i].tfm)) {
+			if (algo == HASH_ALGO_SHA1) {
+				rc = PTR_ERR(ima_algo_array[i].tfm);
+				ima_algo_array[i].tfm = NULL;
+				goto out_array;
+			}
+
+			ima_algo_array[i].tfm = NULL;
+		}
+	}
+
+	if (ima_sha1_idx >= NR_BANKS(ima_tpm_chip)) {
+		if (ima_hash_algo == HASH_ALGO_SHA1) {
+			ima_algo_array[ima_sha1_idx].tfm = ima_shash_tfm;
+		} else {
+			ima_algo_array[ima_sha1_idx].tfm =
+						ima_alloc_tfm(HASH_ALGO_SHA1);
+			if (IS_ERR(ima_algo_array[ima_sha1_idx].tfm)) {
+				rc = PTR_ERR(ima_algo_array[ima_sha1_idx].tfm);
+				goto out_array;
+			}
+		}
+
+		ima_algo_array[ima_sha1_idx].algo = HASH_ALGO_SHA1;
+	}
+
+	return 0;
+out_array:
+	for (i = 0; i < NR_BANKS(ima_tpm_chip) + ima_extra_slots; i++) {
+		if (!ima_algo_array[i].tfm ||
+		    ima_algo_array[i].tfm == ima_shash_tfm)
+			continue;
+
+		crypto_free_shash(ima_algo_array[i].tfm);
+	}
+out:
+	crypto_free_shash(ima_shash_tfm);
+	return rc;
+}
+
 static void ima_free_tfm(struct crypto_shash *tfm)
 {
-	if (tfm != ima_shash_tfm)
-		crypto_free_shash(tfm);
+	int i;
+
+	if (tfm == ima_shash_tfm)
+		return;
+
+	for (i = 0; i < NR_BANKS(ima_tpm_chip) + ima_extra_slots; i++)
+		if (ima_algo_array[i].tfm == tfm)
+			return;
+
+	crypto_free_shash(tfm);
 }
 
 /**
@@ -472,14 +574,14 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash)
  */
 static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
 					 struct ima_template_entry *entry,
-					 struct crypto_shash *tfm)
+					 int tfm_idx)
 {
-	SHASH_DESC_ON_STACK(shash, tfm);
+	SHASH_DESC_ON_STACK(shash, ima_algo_array[tfm_idx].tfm);
 	struct ima_template_desc *td = entry->template_desc;
 	int num_fields = entry->template_desc->num_fields;
 	int rc, i;
 
-	shash->tfm = tfm;
+	shash->tfm = ima_algo_array[tfm_idx].tfm;
 
 	rc = crypto_shash_init(shash);
 	if (rc != 0)
@@ -509,8 +611,7 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
 	}
 
 	if (!rc)
-		rc = crypto_shash_final(shash,
-					entry->digests[ima_sha1_idx].digest);
+		rc = crypto_shash_final(shash, entry->digests[tfm_idx].digest);
 
 	return rc;
 }
@@ -518,17 +619,9 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
 int ima_calc_field_array_hash(struct ima_field_data *field_data,
 			      struct ima_template_entry *entry)
 {
-	struct crypto_shash *tfm;
 	int rc;
 
-	tfm = ima_alloc_tfm(HASH_ALGO_SHA1);
-	if (IS_ERR(tfm))
-		return PTR_ERR(tfm);
-
-	rc = ima_calc_field_array_hash_tfm(field_data, entry, tfm);
-
-	ima_free_tfm(tfm);
-
+	rc = ima_calc_field_array_hash_tfm(field_data, entry, ima_sha1_idx);
 	return rc;
 }
 

From 1ea973df6e2166d1a576cabe5d08925d3261ff9d Mon Sep 17 00:00:00 2001
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: Wed, 25 Mar 2020 11:53:50 +0100
Subject: [PATCH 06/15] 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>
---
 security/integrity/ima/ima_crypto.c   | 29 +++++++++++++++++++++++++-
 security/integrity/ima/ima_queue.c    | 30 ++++++++++++++++-----------
 security/integrity/ima/ima_template.c | 14 +++++++++++--
 3 files changed, 58 insertions(+), 15 deletions(-)

diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index ab1c05ad1314..a94972d3f929 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -619,9 +619,36 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
 int ima_calc_field_array_hash(struct ima_field_data *field_data,
 			      struct ima_template_entry *entry)
 {
-	int rc;
+	u16 alg_id;
+	int rc, i;
 
 	rc = ima_calc_field_array_hash_tfm(field_data, entry, ima_sha1_idx);
+	if (rc)
+		return rc;
+
+	entry->digests[ima_sha1_idx].alg_id = TPM_ALG_SHA1;
+
+	for (i = 0; i < NR_BANKS(ima_tpm_chip) + ima_extra_slots; i++) {
+		if (i == ima_sha1_idx)
+			continue;
+
+		if (i < NR_BANKS(ima_tpm_chip)) {
+			alg_id = ima_tpm_chip->allocated_banks[i].alg_id;
+			entry->digests[i].alg_id = alg_id;
+		}
+
+		/* for unmapped TPM algorithms digest is still a padded SHA1 */
+		if (!ima_algo_array[i].tfm) {
+			memcpy(entry->digests[i].digest,
+			       entry->digests[ima_sha1_idx].digest,
+			       TPM_DIGEST_SIZE);
+			continue;
+		}
+
+		rc = ima_calc_field_array_hash_tfm(field_data, entry, i);
+		if (rc)
+			return rc;
+	}
 	return rc;
 }
 
diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c
index 49db71c200b4..82a9ca43b989 100644
--- a/security/integrity/ima/ima_queue.c
+++ b/security/integrity/ima/ima_queue.c
@@ -135,18 +135,14 @@ unsigned long ima_get_binary_runtime_size(void)
 		return binary_runtime_size + sizeof(struct ima_kexec_hdr);
 };
 
-static int ima_pcr_extend(const u8 *hash, int pcr)
+static int ima_pcr_extend(struct tpm_digest *digests_arg, int pcr)
 {
 	int result = 0;
-	int i;
 
 	if (!ima_tpm_chip)
 		return result;
 
-	for (i = 0; i < ima_tpm_chip->nr_allocated_banks; i++)
-		memcpy(digests[i].digest, hash, TPM_DIGEST_SIZE);
-
-	result = tpm_pcr_extend(ima_tpm_chip, pcr, digests);
+	result = tpm_pcr_extend(ima_tpm_chip, pcr, digests_arg);
 	if (result != 0)
 		pr_err("Error Communicating to TPM chip, result: %d\n", result);
 	return result;
@@ -164,7 +160,8 @@ int ima_add_template_entry(struct ima_template_entry *entry, int violation,
 			   const char *op, struct inode *inode,
 			   const unsigned char *filename)
 {
-	u8 digest[TPM_DIGEST_SIZE];
+	u8 *digest = entry->digests[ima_sha1_idx].digest;
+	struct tpm_digest *digests_arg = entry->digests;
 	const char *audit_cause = "hash_added";
 	char tpm_audit_cause[AUDIT_CAUSE_LEN_MAX];
 	int audit_info = 1;
@@ -172,8 +169,6 @@ int ima_add_template_entry(struct ima_template_entry *entry, int violation,
 
 	mutex_lock(&ima_extend_list_mutex);
 	if (!violation) {
-		memcpy(digest, entry->digests[ima_sha1_idx].digest,
-		       sizeof(digest));
 		if (ima_lookup_digest_entry(digest, entry->pcr)) {
 			audit_cause = "hash_exists";
 			result = -EEXIST;
@@ -189,9 +184,9 @@ int ima_add_template_entry(struct ima_template_entry *entry, int violation,
 	}
 
 	if (violation)		/* invalidate pcr */
-		memset(digest, 0xff, sizeof(digest));
+		digests_arg = digests;
 
-	tpmresult = ima_pcr_extend(digest, entry->pcr);
+	tpmresult = ima_pcr_extend(digests_arg, entry->pcr);
 	if (tpmresult != 0) {
 		snprintf(tpm_audit_cause, AUDIT_CAUSE_LEN_MAX, "TPM_error(%d)",
 			 tpmresult);
@@ -217,6 +212,8 @@ int ima_restore_measurement_entry(struct ima_template_entry *entry)
 
 int __init ima_init_digests(void)
 {
+	u16 digest_size;
+	u16 crypto_id;
 	int i;
 
 	if (!ima_tpm_chip)
@@ -227,8 +224,17 @@ int __init ima_init_digests(void)
 	if (!digests)
 		return -ENOMEM;
 
-	for (i = 0; i < ima_tpm_chip->nr_allocated_banks; i++)
+	for (i = 0; i < ima_tpm_chip->nr_allocated_banks; i++) {
 		digests[i].alg_id = ima_tpm_chip->allocated_banks[i].alg_id;
+		digest_size = ima_tpm_chip->allocated_banks[i].digest_size;
+		crypto_id = ima_tpm_chip->allocated_banks[i].crypto_id;
+
+		/* for unmapped TPM algorithms digest is still a padded SHA1 */
+		if (crypto_id == HASH_ALGO__LAST)
+			digest_size = SHA1_DIGEST_SIZE;
+
+		memset(digests[i].digest, 0xff, digest_size);
+	}
 
 	return 0;
 }
diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c
index de84252e65e9..5a2def40a733 100644
--- a/security/integrity/ima/ima_template.c
+++ b/security/integrity/ima/ima_template.c
@@ -357,6 +357,7 @@ static int ima_restore_template_data(struct ima_template_desc *template_desc,
 int ima_restore_measurement_list(loff_t size, void *buf)
 {
 	char template_name[MAX_TEMPLATE_NAME_LEN];
+	unsigned char zero[TPM_DIGEST_SIZE] = { 0 };
 
 	struct ima_kexec_hdr *khdr = buf;
 	struct ima_field_data hdr[HDR__LAST] = {
@@ -456,8 +457,17 @@ int ima_restore_measurement_list(loff_t size, void *buf)
 		if (ret < 0)
 			break;
 
-		memcpy(entry->digests[ima_sha1_idx].digest,
-		       hdr[HDR_DIGEST].data, hdr[HDR_DIGEST].len);
+		if (memcmp(hdr[HDR_DIGEST].data, zero, sizeof(zero))) {
+			ret = ima_calc_field_array_hash(
+						&entry->template_data[0],
+						entry);
+			if (ret < 0) {
+				pr_err("cannot calculate template digest\n");
+				ret = -EINVAL;
+				break;
+			}
+		}
+
 		entry->pcr = !ima_canonical_fmt ? *(hdr[HDR_PCR].data) :
 			     le32_to_cpu(*(hdr[HDR_PCR].data));
 		ret = ima_restore_measurement_entry(entry);

From 2592677c0486e64a08e0b930a7dfa6fbf77e6fc1 Mon Sep 17 00:00:00 2001
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: Wed, 25 Mar 2020 11:54:24 +0100
Subject: [PATCH 07/15] 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>
---
 security/integrity/ima/ima.h        |  1 +
 security/integrity/ima/ima_crypto.c | 19 ++++++++++++++++++-
 security/integrity/ima/ima_queue.c  |  8 ++++----
 3 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 2a7ed68e6414..467dfdbea25c 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -53,6 +53,7 @@ extern int ima_policy_flag;
 /* set during initialization */
 extern int ima_hash_algo;
 extern int ima_sha1_idx __ro_after_init;
+extern int ima_hash_algo_idx __ro_after_init;
 extern int ima_extra_slots __ro_after_init;
 extern int ima_appraise;
 extern struct tpm_chip *ima_tpm_chip;
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index a94972d3f929..5201f5ec2ce4 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -63,6 +63,7 @@ struct ima_algo_desc {
 };
 
 int ima_sha1_idx __ro_after_init;
+int ima_hash_algo_idx __ro_after_init;
 /*
  * Additional number of slots reserved, as needed, for SHA1
  * and IMA default algo.
@@ -122,15 +123,25 @@ int __init ima_init_crypto(void)
 		return rc;
 
 	ima_sha1_idx = -1;
+	ima_hash_algo_idx = -1;
 
 	for (i = 0; i < NR_BANKS(ima_tpm_chip); i++) {
 		algo = ima_tpm_chip->allocated_banks[i].crypto_id;
 		if (algo == HASH_ALGO_SHA1)
 			ima_sha1_idx = i;
+
+		if (algo == ima_hash_algo)
+			ima_hash_algo_idx = i;
 	}
 
-	if (ima_sha1_idx < 0)
+	if (ima_sha1_idx < 0) {
 		ima_sha1_idx = NR_BANKS(ima_tpm_chip) + ima_extra_slots++;
+		if (ima_hash_algo == HASH_ALGO_SHA1)
+			ima_hash_algo_idx = ima_sha1_idx;
+	}
+
+	if (ima_hash_algo_idx < 0)
+		ima_hash_algo_idx = NR_BANKS(ima_tpm_chip) + ima_extra_slots++;
 
 	ima_algo_array = kcalloc(NR_BANKS(ima_tpm_chip) + ima_extra_slots,
 				 sizeof(*ima_algo_array), GFP_KERNEL);
@@ -179,6 +190,12 @@ int __init ima_init_crypto(void)
 		ima_algo_array[ima_sha1_idx].algo = HASH_ALGO_SHA1;
 	}
 
+	if (ima_hash_algo_idx >= NR_BANKS(ima_tpm_chip) &&
+	    ima_hash_algo_idx != ima_sha1_idx) {
+		ima_algo_array[ima_hash_algo_idx].tfm = ima_shash_tfm;
+		ima_algo_array[ima_hash_algo_idx].algo = ima_hash_algo;
+	}
+
 	return 0;
 out_array:
 	for (i = 0; i < NR_BANKS(ima_tpm_chip) + ima_extra_slots; i++) {
diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c
index 82a9ca43b989..fb4ec270f620 100644
--- a/security/integrity/ima/ima_queue.c
+++ b/security/integrity/ima/ima_queue.c
@@ -55,8 +55,8 @@ static struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest_value,
 	key = ima_hash_key(digest_value);
 	rcu_read_lock();
 	hlist_for_each_entry_rcu(qe, &ima_htable.queue[key], hnext) {
-		rc = memcmp(qe->entry->digests[ima_sha1_idx].digest,
-			    digest_value, TPM_DIGEST_SIZE);
+		rc = memcmp(qe->entry->digests[ima_hash_algo_idx].digest,
+			    digest_value, hash_digest_size[ima_hash_algo]);
 		if ((rc == 0) && (qe->entry->pcr == pcr)) {
 			ret = qe;
 			break;
@@ -108,7 +108,7 @@ static int ima_add_digest_entry(struct ima_template_entry *entry,
 
 	atomic_long_inc(&ima_htable.len);
 	if (update_htable) {
-		key = ima_hash_key(entry->digests[ima_sha1_idx].digest);
+		key = ima_hash_key(entry->digests[ima_hash_algo_idx].digest);
 		hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);
 	}
 
@@ -160,7 +160,7 @@ int ima_add_template_entry(struct ima_template_entry *entry, int violation,
 			   const char *op, struct inode *inode,
 			   const unsigned char *filename)
 {
-	u8 *digest = entry->digests[ima_sha1_idx].digest;
+	u8 *digest = entry->digests[ima_hash_algo_idx].digest;
 	struct tpm_digest *digests_arg = entry->digests;
 	const char *audit_cause = "hash_added";
 	char tpm_audit_cause[AUDIT_CAUSE_LEN_MAX];

From 1129d31b55d509f15e72dc68e4b5c3a4d7b4da8d Mon Sep 17 00:00:00 2001
From: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Date: Tue, 28 Apr 2020 09:30:10 +0200
Subject: [PATCH 08/15] 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: 3323eec921ef ("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>
---
 security/integrity/ima/ima.h | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 467dfdbea25c..02796473238b 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -36,7 +36,7 @@ enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
 #define IMA_DIGEST_SIZE		SHA1_DIGEST_SIZE
 #define IMA_EVENT_NAME_LEN_MAX	255
 
-#define IMA_HASH_BITS 9
+#define IMA_HASH_BITS 10
 #define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS)
 
 #define IMA_TEMPLATE_FIELD_ID_MAX_LEN	16
@@ -179,9 +179,10 @@ struct ima_h_table {
 };
 extern struct ima_h_table ima_htable;
 
-static inline unsigned long ima_hash_key(u8 *digest)
+static inline unsigned int ima_hash_key(u8 *digest)
 {
-	return hash_long(*digest, IMA_HASH_BITS);
+	/* there is no point in taking a hash of part of a digest */
+	return (digest[0] | digest[1] << 8) % IMA_MEASURE_HTABLE_SIZE;
 }
 
 #define __ima_hooks(hook)		\

From 6ee28442a465ab4c4be45e3b15015af24b1ba906 Mon Sep 17 00:00:00 2001
From: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Date: Mon, 27 Apr 2020 12:28:58 +0200
Subject: [PATCH 09/15] 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>
---
 security/integrity/ima/ima_policy.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index c334e0dc6083..ea9b991f0232 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -643,11 +643,8 @@ static void add_rules(struct ima_rule_entry *entries, int count,
 
 			list_add_tail(&entry->list, &ima_policy_rules);
 		}
-		if (entries[i].action == APPRAISE) {
+		if (entries[i].action == APPRAISE)
 			temp_ima_appraise |= ima_appraise_flag(entries[i].func);
-			if (entries[i].func == POLICY_CHECK)
-				temp_ima_appraise |= IMA_APPRAISE_POLICY;
-		}
 	}
 }
 

From b59fda449cf07f2db3be3a67142e6c000f5e8d79 Mon Sep 17 00:00:00 2001
From: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Date: Mon, 27 Apr 2020 12:28:59 +0200
Subject: [PATCH 10/15] ima: Set again build_ima_appraise variable

After adding the new add_rule() function in commit c52657d93b05
("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: c52657d93b05 ("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>
---
 security/integrity/ima/ima_policy.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index ea9b991f0232..ef7f68cc935e 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -643,8 +643,14 @@ static void add_rules(struct ima_rule_entry *entries, int count,
 
 			list_add_tail(&entry->list, &ima_policy_rules);
 		}
-		if (entries[i].action == APPRAISE)
-			temp_ima_appraise |= ima_appraise_flag(entries[i].func);
+		if (entries[i].action == APPRAISE) {
+			if (entries != build_appraise_rules)
+				temp_ima_appraise |=
+					ima_appraise_flag(entries[i].func);
+			else
+				build_ima_appraise |=
+					ima_appraise_flag(entries[i].func);
+		}
 	}
 }
 

From 0c4395fb2aa77341269ea619c5419ea48171883f Mon Sep 17 00:00:00 2001
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: Tue, 14 Apr 2020 10:01:31 +0200
Subject: [PATCH 11/15] 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: 50b977481fce9 ("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>
---
 security/integrity/evm/evm_crypto.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c
index 35682852ddea..499ea01b2edc 100644
--- a/security/integrity/evm/evm_crypto.c
+++ b/security/integrity/evm/evm_crypto.c
@@ -241,7 +241,7 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry,
 
 	/* Portable EVM signatures must include an IMA hash */
 	if (type == EVM_XATTR_PORTABLE_DIGSIG && !ima_present)
-		return -EPERM;
+		error = -EPERM;
 out:
 	kfree(xattr_value);
 	kfree(desc);

From 8eb613c0b8f19627ba1846dcf78bb2c85edbe8dd Mon Sep 17 00:00:00 2001
From: Mimi Zohar <zohar@linux.ibm.com>
Date: Sun, 3 May 2020 01:00:02 -0400
Subject: [PATCH 12/15] 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>
---
 include/linux/ima.h               |  7 +++++
 security/integrity/ima/ima_main.c | 51 +++++++++++++++++++++++++++++++
 security/security.c               |  7 ++++-
 3 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/include/linux/ima.h b/include/linux/ima.h
index aefe758f4466..9164e1534ec9 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h
@@ -18,6 +18,7 @@ extern int ima_file_check(struct file *file, int mask);
 extern void ima_post_create_tmpfile(struct inode *inode);
 extern void ima_file_free(struct file *file);
 extern int ima_file_mmap(struct file *file, unsigned long prot);
+extern int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot);
 extern int ima_load_data(enum kernel_load_data_id id);
 extern int ima_read_file(struct file *file, enum kernel_read_file_id id);
 extern int ima_post_read_file(struct file *file, void *buf, loff_t size,
@@ -70,6 +71,12 @@ static inline int ima_file_mmap(struct file *file, unsigned long prot)
 	return 0;
 }
 
+static inline int ima_file_mprotect(struct vm_area_struct *vma,
+				    unsigned long prot)
+{
+	return 0;
+}
+
 static inline int ima_load_data(enum kernel_load_data_id id)
 {
 	return 0;
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index f96f151294e6..800fb3bba418 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -393,6 +393,57 @@ int ima_file_mmap(struct file *file, unsigned long prot)
 	return 0;
 }
 
+/**
+ * ima_file_mprotect - based on policy, limit mprotect change
+ * @prot: contains the protection that will be applied by the kernel.
+ *
+ * Files can be mmap'ed read/write and later changed to execute to circumvent
+ * IMA's mmap appraisal policy rules.  Due to locking issues (mmap semaphore
+ * would be taken before 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.
+ */
+int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot)
+{
+	struct ima_template_desc *template;
+	struct file *file = vma->vm_file;
+	char filename[NAME_MAX];
+	char *pathbuf = NULL;
+	const char *pathname = NULL;
+	struct inode *inode;
+	int result = 0;
+	int action;
+	u32 secid;
+	int pcr;
+
+	/* Is mprotect making an mmap'ed file executable? */
+	if (!vma->vm_file || !(prot & PROT_EXEC) || (vma->vm_flags & VM_EXEC))
+		return 0;
+
+	security_task_getsecid(current, &secid);
+	inode = file_inode(vma->vm_file);
+	action = ima_get_action(inode, current_cred(), secid, MAY_EXEC,
+				MMAP_CHECK, &pcr, &template, 0);
+
+	/* Is the mmap'ed file in policy? */
+	if (!(action & (IMA_MEASURE | IMA_APPRAISE_SUBMASK)))
+		return 0;
+
+	if (action & IMA_APPRAISE_SUBMASK)
+		result = -EPERM;
+
+	file = vma->vm_file;
+	pathname = ima_d_path(&file->f_path, &pathbuf, filename);
+	integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, pathname,
+			    "collect_data", "failed-mprotect", result, 0);
+	if (pathbuf)
+		__putname(pathbuf);
+
+	return result;
+}
+
 /**
  * ima_bprm_check - based on policy, collect/store measurement.
  * @bprm: contains the linux_binprm structure
diff --git a/security/security.c b/security/security.c
index 7fed24b9d57e..dd0917c5bfe9 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1512,7 +1512,12 @@ int security_mmap_addr(unsigned long addr)
 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
 			    unsigned long prot)
 {
-	return call_int_hook(file_mprotect, 0, vma, reqprot, prot);
+	int ret;
+
+	ret = call_int_hook(file_mprotect, 0, vma, reqprot, prot);
+	if (ret)
+		return ret;
+	return ima_file_mprotect(vma, prot);
 }
 
 int security_file_lock(struct file *file, unsigned int cmd)

From 067a436b1b0aafa593344fddd711a755a58afb3b Mon Sep 17 00:00:00 2001
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: Wed, 3 Jun 2020 17:08:20 +0200
Subject: [PATCH 13/15] 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: 07f6a79415d7d ("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>
---
 security/integrity/ima/ima_policy.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index ef7f68cc935e..e493063a3c34 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -204,7 +204,7 @@ static struct ima_rule_entry *arch_policy_entry __ro_after_init;
 static LIST_HEAD(ima_default_rules);
 static LIST_HEAD(ima_policy_rules);
 static LIST_HEAD(ima_temp_rules);
-static struct list_head *ima_rules;
+static struct list_head *ima_rules = &ima_default_rules;
 
 /* Pre-allocated buffer used for matching keyrings. */
 static char *ima_keyrings;
@@ -768,7 +768,6 @@ void __init ima_init_policy(void)
 			  ARRAY_SIZE(default_appraise_rules),
 			  IMA_DEFAULT_POLICY);
 
-	ima_rules = &ima_default_rules;
 	ima_update_policy_flag();
 }
 

From 6cc7c266e5b47d3cd2b5bb7fd3aac4e6bb2dd1d2 Mon Sep 17 00:00:00 2001
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: Wed, 3 Jun 2020 17:08:21 +0200
Subject: [PATCH 14/15] 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: 3ce1217d6cd5d ("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>
---
 security/integrity/ima/ima.h              |  3 ++-
 security/integrity/ima/ima_crypto.c       |  6 +++---
 security/integrity/ima/ima_init.c         |  2 +-
 security/integrity/ima/ima_template_lib.c | 18 ++++++++++++++++++
 4 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 02796473238b..df93ac258e01 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -57,6 +57,7 @@ extern int ima_hash_algo_idx __ro_after_init;
 extern int ima_extra_slots __ro_after_init;
 extern int ima_appraise;
 extern struct tpm_chip *ima_tpm_chip;
+extern const char boot_aggregate_name[];
 
 /* IMA event related data */
 struct ima_event_data {
@@ -144,7 +145,7 @@ int ima_calc_buffer_hash(const void *buf, loff_t len,
 			 struct ima_digest_data *hash);
 int ima_calc_field_array_hash(struct ima_field_data *field_data,
 			      struct ima_template_entry *entry);
-int __init ima_calc_boot_aggregate(struct ima_digest_data *hash);
+int ima_calc_boot_aggregate(struct ima_digest_data *hash);
 void ima_add_violation(struct file *file, const unsigned char *filename,
 		       struct integrity_iint_cache *iint,
 		       const char *op, const char *cause);
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index 5201f5ec2ce4..002fdf6994d5 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -806,8 +806,8 @@ static void __init ima_pcrread(u32 idx, struct tpm_digest *d)
  * hash algorithm for reading the TPM PCRs as for calculating the boot
  * aggregate digest as stored in the measurement list.
  */
-static int __init ima_calc_boot_aggregate_tfm(char *digest, u16 alg_id,
-					      struct crypto_shash *tfm)
+static int ima_calc_boot_aggregate_tfm(char *digest, u16 alg_id,
+				       struct crypto_shash *tfm)
 {
 	struct tpm_digest d = { .alg_id = alg_id, .digest = {0} };
 	int rc;
@@ -835,7 +835,7 @@ static int __init ima_calc_boot_aggregate_tfm(char *digest, u16 alg_id,
 	return rc;
 }
 
-int __init ima_calc_boot_aggregate(struct ima_digest_data *hash)
+int ima_calc_boot_aggregate(struct ima_digest_data *hash)
 {
 	struct crypto_shash *tfm;
 	u16 crypto_id, alg_id;
diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c
index fc1e1002b48d..4902fe7bd570 100644
--- a/security/integrity/ima/ima_init.c
+++ b/security/integrity/ima/ima_init.c
@@ -19,7 +19,7 @@
 #include "ima.h"
 
 /* name for boot aggregate entry */
-static const char boot_aggregate_name[] = "boot_aggregate";
+const char boot_aggregate_name[] = "boot_aggregate";
 struct tpm_chip *ima_tpm_chip;
 
 /* Add the boot aggregate to the IMA measurement list and extend
diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c
index 9cd1e50f3ccc..635c6ac05050 100644
--- a/security/integrity/ima/ima_template_lib.c
+++ b/security/integrity/ima/ima_template_lib.c
@@ -286,6 +286,24 @@ int ima_eventdigest_init(struct ima_event_data *event_data,
 		goto out;
 	}
 
+	if ((const char *)event_data->filename == boot_aggregate_name) {
+		if (ima_tpm_chip) {
+			hash.hdr.algo = HASH_ALGO_SHA1;
+			result = ima_calc_boot_aggregate(&hash.hdr);
+
+			/* algo can change depending on available PCR banks */
+			if (!result && hash.hdr.algo != HASH_ALGO_SHA1)
+				result = -EINVAL;
+
+			if (result < 0)
+				memset(&hash, 0, sizeof(hash));
+		}
+
+		cur_digest = hash.hdr.digest;
+		cur_digestsize = hash_digest_size[HASH_ALGO_SHA1];
+		goto out;
+	}
+
 	if (!event_data->file)	/* missing info to re-calculate the digest */
 		return -EINVAL;
 

From 42413b49804b250ced70dac8815388af2d4ad872 Mon Sep 17 00:00:00 2001
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: Fri, 5 Jun 2020 08:50:28 +0200
Subject: [PATCH 15/15] 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 aa724fe18a8a
("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: aa724fe18a8a ("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>
---
 security/integrity/ima/ima_api.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 78e0b0a7723e..bf22de8b7ce0 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -55,8 +55,9 @@ int ima_alloc_init_template(struct ima_event_data *event_data,
 	digests = kcalloc(NR_BANKS(ima_tpm_chip) + ima_extra_slots,
 			  sizeof(*digests), GFP_NOFS);
 	if (!digests) {
-		result = -ENOMEM;
-		goto out;
+		kfree(*entry);
+		*entry = NULL;
+		return -ENOMEM;
 	}
 
 	(*entry)->digests = digests;