diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-10-15 15:58:18 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-10-15 15:58:18 -0700 |
commit | 840e5bb326bbcb16ce82dd2416d2769de4839aea (patch) | |
tree | 0db7a077c3ae35dd99a89f0128b760951d95db72 | |
parent | fefa636d815975b34afc45f50852a2810fb23ba9 (diff) | |
parent | aa662fc04f5b290b3979332588bf8d812b189962 (diff) |
Merge tag 'integrity-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:
"Continuing IMA policy rule cleanup and validation in particular for
measuring keys, adding/removing/updating informational and error
messages (e.g. "ima_appraise" boot command line option), and other bug
fixes (e.g. minimal data size validation before use, return code and
NULL pointer checking)"
* tag 'integrity-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
ima: Fix NULL pointer dereference in ima_file_hash
evm: Check size of security.evm before using it
ima: Remove semicolon at the end of ima_get_binary_runtime_size()
ima: Don't ignore errors from crypto_shash_update()
ima: Use kmemdup rather than kmalloc+memcpy
integrity: include keyring name for unknown key request
ima: limit secure boot feedback scope for appraise
integrity: invalid kernel parameters feedback
ima: add check for enforced appraise option
integrity: Use current_uid() in integrity_audit_message()
ima: Fail rule parsing when asymmetric key measurement isn't supportable
ima: Pre-parse the list of keyrings in a KEY_CHECK rule
-rw-r--r-- | security/integrity/digsig_asymmetric.c | 10 | ||||
-rw-r--r-- | security/integrity/evm/evm_main.c | 9 | ||||
-rw-r--r-- | security/integrity/ima/ima_appraise.c | 27 | ||||
-rw-r--r-- | security/integrity/ima/ima_crypto.c | 2 | ||||
-rw-r--r-- | security/integrity/ima/ima_main.c | 23 | ||||
-rw-r--r-- | security/integrity/ima/ima_policy.c | 153 | ||||
-rw-r--r-- | security/integrity/ima/ima_queue.c | 2 | ||||
-rw-r--r-- | security/integrity/integrity_audit.c | 2 |
8 files changed, 161 insertions, 67 deletions
diff --git a/security/integrity/digsig_asymmetric.c b/security/integrity/digsig_asymmetric.c index b86a4a8f61ab..a662024b4c70 100644 --- a/security/integrity/digsig_asymmetric.c +++ b/security/integrity/digsig_asymmetric.c @@ -55,8 +55,14 @@ static struct key *request_asymmetric_key(struct key *keyring, uint32_t keyid) } if (IS_ERR(key)) { - pr_err_ratelimited("Request for unknown key '%s' err %ld\n", - name, PTR_ERR(key)); + if (keyring) + pr_err_ratelimited("Request for unknown key '%s' in '%s' keyring. err %ld\n", + name, keyring->description, + PTR_ERR(key)); + else + pr_err_ratelimited("Request for unknown key '%s' err %ld\n", + name, PTR_ERR(key)); + switch (PTR_ERR(key)) { /* Hide some search errors */ case -EACCES: diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index 0d36259b690d..76d19146d74b 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -59,6 +59,9 @@ static int __init evm_set_fixmode(char *str) { if (strncmp(str, "fix", 3) == 0) evm_fixmode = 1; + else + pr_err("invalid \"%s\" mode", str); + return 0; } __setup("evm=", evm_set_fixmode); @@ -181,6 +184,12 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry, break; case EVM_IMA_XATTR_DIGSIG: case EVM_XATTR_PORTABLE_DIGSIG: + /* accept xattr with non-empty signature field */ + if (xattr_len <= sizeof(struct signature_v2_hdr)) { + evm_status = INTEGRITY_FAIL; + goto out; + } + hdr = (struct signature_v2_hdr *)xattr_data; digest.hdr.algo = hdr->hash_algo; rc = evm_calc_hash(dentry, xattr_name, xattr_value, diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index b8848f53c8cc..3dd8c2e4314e 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -19,18 +19,29 @@ static int __init default_appraise_setup(char *str) { #ifdef CONFIG_IMA_APPRAISE_BOOTPARAM - if (arch_ima_get_secureboot()) { - pr_info("Secure boot enabled: ignoring ima_appraise=%s boot parameter option", - str); - return 1; - } + bool sb_state = arch_ima_get_secureboot(); + int appraisal_state = ima_appraise; if (strncmp(str, "off", 3) == 0) - ima_appraise = 0; + appraisal_state = 0; else if (strncmp(str, "log", 3) == 0) - ima_appraise = IMA_APPRAISE_LOG; + appraisal_state = IMA_APPRAISE_LOG; else if (strncmp(str, "fix", 3) == 0) - ima_appraise = IMA_APPRAISE_FIX; + appraisal_state = IMA_APPRAISE_FIX; + else if (strncmp(str, "enforce", 7) == 0) + appraisal_state = IMA_APPRAISE_ENFORCE; + else + pr_err("invalid \"%s\" appraise option", str); + + /* If appraisal state was changed, but secure boot is enabled, + * keep its default */ + if (sb_state) { + if (!(appraisal_state & IMA_APPRAISE_ENFORCE)) + pr_info("Secure boot enabled: ignoring ima_appraise=%s option", + str); + } else { + ima_appraise = appraisal_state; + } #endif return 1; } diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c index 011c3c76af86..21989fa0c107 100644 --- a/security/integrity/ima/ima_crypto.c +++ b/security/integrity/ima/ima_crypto.c @@ -829,6 +829,8 @@ static int ima_calc_boot_aggregate_tfm(char *digest, u16 alg_id, /* now accumulate with current aggregate */ rc = crypto_shash_update(shash, d.digest, crypto_shash_digestsize(tfm)); + if (rc != 0) + return rc; } /* * Extend cumulative digest over TPM registers 8-9, which contain diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 82c9d62bcb11..2d1af8899cab 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -51,18 +51,23 @@ static int __init hash_setup(char *str) return 1; if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) { - if (strncmp(str, "sha1", 4) == 0) + if (strncmp(str, "sha1", 4) == 0) { ima_hash_algo = HASH_ALGO_SHA1; - else if (strncmp(str, "md5", 3) == 0) + } else if (strncmp(str, "md5", 3) == 0) { ima_hash_algo = HASH_ALGO_MD5; - else + } else { + pr_err("invalid hash algorithm \"%s\" for template \"%s\"", + str, IMA_TEMPLATE_IMA_NAME); return 1; + } goto out; } i = match_string(hash_algo_name, HASH_ALGO__LAST, str); - if (i < 0) + if (i < 0) { + pr_err("invalid hash algorithm \"%s\"", str); return 1; + } ima_hash_algo = i; out: @@ -532,6 +537,16 @@ int ima_file_hash(struct file *file, char *buf, size_t buf_size) return -EOPNOTSUPP; mutex_lock(&iint->mutex); + + /* + * ima_file_hash can be called when ima_collect_measurement has still + * not been called, we might not always have a hash. + */ + if (!iint->ima_hash) { + mutex_unlock(&iint->mutex); + return -EOPNOTSUPP; + } + if (buf) { size_t copied_size; diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 3b0b43e18ecf..9b5adeaa47fc 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -60,6 +60,11 @@ enum policy_types { ORIGINAL_TCB = 1, DEFAULT_TCB }; enum policy_rule_list { IMA_DEFAULT_POLICY = 1, IMA_CUSTOM_POLICY }; +struct ima_rule_opt_list { + size_t count; + char *items[]; +}; + struct ima_rule_entry { struct list_head list; int action; @@ -79,7 +84,7 @@ struct ima_rule_entry { int type; /* audit type */ } lsm[MAX_LSM_RULES]; char *fsname; - char *keyrings; /* Measure keys added to these keyrings */ + struct ima_rule_opt_list *keyrings; /* Measure keys added to these keyrings */ struct ima_template_desc *template; }; @@ -207,10 +212,6 @@ static LIST_HEAD(ima_policy_rules); static LIST_HEAD(ima_temp_rules); static struct list_head *ima_rules = &ima_default_rules; -/* Pre-allocated buffer used for matching keyrings. */ -static char *ima_keyrings; -static size_t ima_keyrings_len; - static int ima_policy __initdata; static int __init default_measure_policy_setup(char *str) @@ -241,6 +242,8 @@ static int __init policy_setup(char *str) ima_use_secure_boot = true; else if (strcmp(p, "fail_securely") == 0) ima_fail_unverifiable_sigs = true; + else + pr_err("policy \"%s\" not found", p); } return 1; @@ -254,6 +257,72 @@ static int __init default_appraise_policy_setup(char *str) } __setup("ima_appraise_tcb", default_appraise_policy_setup); +static struct ima_rule_opt_list *ima_alloc_rule_opt_list(const substring_t *src) +{ + struct ima_rule_opt_list *opt_list; + size_t count = 0; + char *src_copy; + char *cur, *next; + size_t i; + + src_copy = match_strdup(src); + if (!src_copy) + return ERR_PTR(-ENOMEM); + + next = src_copy; + while ((cur = strsep(&next, "|"))) { + /* Don't accept an empty list item */ + if (!(*cur)) { + kfree(src_copy); + return ERR_PTR(-EINVAL); + } + count++; + } + + /* Don't accept an empty list */ + if (!count) { + kfree(src_copy); + return ERR_PTR(-EINVAL); + } + + opt_list = kzalloc(struct_size(opt_list, items, count), GFP_KERNEL); + if (!opt_list) { + kfree(src_copy); + return ERR_PTR(-ENOMEM); + } + + /* + * strsep() has already replaced all instances of '|' with '\0', + * leaving a byte sequence of NUL-terminated strings. Reference each + * string with the array of items. + * + * IMPORTANT: Ownership of the allocated buffer is transferred from + * src_copy to the first element in the items array. To free the + * buffer, kfree() must only be called on the first element of the + * array. + */ + for (i = 0, cur = src_copy; i < count; i++) { + opt_list->items[i] = cur; + cur = strchr(cur, '\0') + 1; + } + opt_list->count = count; + + return opt_list; +} + +static void ima_free_rule_opt_list(struct ima_rule_opt_list *opt_list) +{ + if (!opt_list) + return; + + if (opt_list->count) { + kfree(opt_list->items[0]); + opt_list->count = 0; + } + + kfree(opt_list); +} + static void ima_lsm_free_rule(struct ima_rule_entry *entry) { int i; @@ -275,7 +344,7 @@ static void ima_free_rule(struct ima_rule_entry *entry) * the defined_templates list and cannot be freed here */ kfree(entry->fsname); - kfree(entry->keyrings); + ima_free_rule_opt_list(entry->keyrings); ima_lsm_free_rule(entry); kfree(entry); } @@ -285,15 +354,14 @@ static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry) struct ima_rule_entry *nentry; int i; - nentry = kmalloc(sizeof(*nentry), GFP_KERNEL); - if (!nentry) - return NULL; - /* * Immutable elements are copied over as pointers and data; only * lsm rules can change */ - memcpy(nentry, entry, sizeof(*nentry)); + nentry = kmemdup(entry, sizeof(*nentry), GFP_KERNEL); + if (!nentry) + return NULL; + memset(nentry->lsm, 0, sizeof_field(struct ima_rule_entry, lsm)); for (i = 0; i < MAX_LSM_RULES; i++) { @@ -395,8 +463,8 @@ int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event, static bool ima_match_keyring(struct ima_rule_entry *rule, const char *keyring, const struct cred *cred) { - char *next_keyring, *keyrings_ptr; bool matched = false; + size_t i; if ((rule->flags & IMA_UID) && !rule->uid_op(cred->uid, rule->uid)) return false; @@ -407,15 +475,8 @@ static bool ima_match_keyring(struct ima_rule_entry *rule, if (!keyring) return false; - strcpy(ima_keyrings, rule->keyrings); - - /* - * "keyrings=" is specified in the policy in the format below: - * keyrings=.builtin_trusted_keys|.ima|.evm - */ - keyrings_ptr = ima_keyrings; - while ((next_keyring = strsep(&keyrings_ptr, "|")) != NULL) { - if (!strcmp(next_keyring, keyring)) { + for (i = 0; i < rule->keyrings->count; i++) { + if (!strcmp(rule->keyrings->items[i], keyring)) { matched = true; break; } @@ -1066,7 +1127,6 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) bool uid_token; struct ima_template_desc *template_desc; int result = 0; - size_t keyrings_len; ab = integrity_audit_log_start(audit_context(), GFP_KERNEL, AUDIT_INTEGRITY_POLICY_RULE); @@ -1175,7 +1235,8 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) entry->func = POLICY_CHECK; else if (strcmp(args[0].from, "KEXEC_CMDLINE") == 0) entry->func = KEXEC_CMDLINE; - else if (strcmp(args[0].from, "KEY_CHECK") == 0) + else if (IS_ENABLED(CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS) && + strcmp(args[0].from, "KEY_CHECK") == 0) entry->func = KEY_CHECK; else result = -EINVAL; @@ -1232,37 +1293,19 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) case Opt_keyrings: ima_log_string(ab, "keyrings", args[0].from); - keyrings_len = strlen(args[0].from) + 1; - - if ((entry->keyrings) || - (keyrings_len < 2)) { + if (!IS_ENABLED(CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS) || + entry->keyrings) { result = -EINVAL; break; } - if (keyrings_len > ima_keyrings_len) { - char *tmpbuf; - - tmpbuf = krealloc(ima_keyrings, keyrings_len, - GFP_KERNEL); - if (!tmpbuf) { - result = -ENOMEM; - break; - } - - ima_keyrings = tmpbuf; - ima_keyrings_len = keyrings_len; - } - - entry->keyrings = kstrdup(args[0].from, GFP_KERNEL); - if (!entry->keyrings) { - kfree(ima_keyrings); - ima_keyrings = NULL; - ima_keyrings_len = 0; - result = -ENOMEM; + entry->keyrings = ima_alloc_rule_opt_list(args); + if (IS_ERR(entry->keyrings)) { + result = PTR_ERR(entry->keyrings); + entry->keyrings = NULL; break; } - result = 0; + entry->flags |= IMA_KEYRINGS; break; case Opt_fsuuid: @@ -1575,6 +1618,15 @@ static void policy_func_show(struct seq_file *m, enum ima_hooks func) seq_printf(m, "func=%d ", func); } +static void ima_show_rule_opt_list(struct seq_file *m, + const struct ima_rule_opt_list *opt_list) +{ + size_t i; + + for (i = 0; i < opt_list->count; i++) + seq_printf(m, "%s%s", i ? "|" : "", opt_list->items[i]); +} + int ima_policy_show(struct seq_file *m, void *v) { struct ima_rule_entry *entry = v; @@ -1631,9 +1683,8 @@ int ima_policy_show(struct seq_file *m, void *v) } if (entry->flags & IMA_KEYRINGS) { - if (entry->keyrings != NULL) - snprintf(tbuf, sizeof(tbuf), "%s", entry->keyrings); - seq_printf(m, pt(Opt_keyrings), tbuf); + seq_puts(m, "keyrings="); + ima_show_rule_opt_list(m, entry->keyrings); seq_puts(m, " "); } diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c index fb4ec270f620..c096ef8945c7 100644 --- a/security/integrity/ima/ima_queue.c +++ b/security/integrity/ima/ima_queue.c @@ -133,7 +133,7 @@ unsigned long ima_get_binary_runtime_size(void) return ULONG_MAX; else return binary_runtime_size + sizeof(struct ima_kexec_hdr); -}; +} static int ima_pcr_extend(struct tpm_digest *digests_arg, int pcr) { diff --git a/security/integrity/integrity_audit.c b/security/integrity/integrity_audit.c index f25e7df099c8..29220056207f 100644 --- a/security/integrity/integrity_audit.c +++ b/security/integrity/integrity_audit.c @@ -47,7 +47,7 @@ void integrity_audit_message(int audit_msgno, struct inode *inode, ab = audit_log_start(audit_context(), GFP_KERNEL, audit_msgno); audit_log_format(ab, "pid=%d uid=%u auid=%u ses=%u", task_pid_nr(current), - from_kuid(&init_user_ns, current_cred()->uid), + from_kuid(&init_user_ns, current_uid()), from_kuid(&init_user_ns, audit_get_loginuid(current)), audit_get_sessionid(current)); audit_log_task_context(ab); |