[PATCH v4 08/16] ima: Move measurement list related variables into ima_namespace
STALE1751d
From: Stefan Berger <stefanb@linux.ibm.com>
Date: 2021-12-07 20:22:37
Also in:
linux-security-module, lkml
Subsystem:
extended verification module (evm), integrity measurement architecture (ima), security subsystem, the rest · Maintainers:
Mimi Zohar, Roberto Sassu, Dmitry Kasatkin, Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds
Revision v4 of 10 in this series.
Revisions (10)
Move measurement list related variables into the ima_namespace. This way a front-end like SecurityFS can show the measurement list inside an IMA namespace. Implement ima_free_measurements() to free a list of measurements and call it when an IMA namespace is deleted. Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> --- include/linux/ima.h | 2 ++ security/integrity/ima/ima.h | 4 +-- security/integrity/ima/ima_fs.c | 6 +++-- security/integrity/ima/ima_init_ima_ns.c | 5 ++++ security/integrity/ima/ima_ns.c | 1 + security/integrity/ima/ima_queue.c | 33 ++++++++++++++---------- 6 files changed, 33 insertions(+), 18 deletions(-)
diff --git a/include/linux/ima.h b/include/linux/ima.h
index 929bf87b1bbf..53f944469de7 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h@@ -259,6 +259,8 @@ struct ima_namespace { int ima_policy_flag; struct ima_h_table ima_htable; + struct list_head ima_measurements; + unsigned long binary_runtime_size; }; extern struct ima_namespace init_ima_ns;
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index a7e6c8fb152a..bb9763cd5fb1 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h@@ -104,7 +104,6 @@ struct ima_queue_entry { struct list_head later; /* place in ima_measurements list */ struct ima_template_entry *entry; }; -extern struct list_head ima_measurements; /* list of all measurements */ /* Some details preceding the binary serialized measurement list */ struct ima_kexec_hdr {
@@ -168,8 +167,9 @@ int ima_restore_measurement_entry(struct ima_namespace *ns, struct ima_template_entry *entry); int ima_restore_measurement_list(struct ima_namespace *ns, loff_t bufsize, void *buf); +void ima_free_measurements(struct ima_namespace *ns); int ima_measurements_show(struct seq_file *m, void *v); -unsigned long ima_get_binary_runtime_size(void); +unsigned long ima_get_binary_runtime_size(struct ima_namespace *ns); int ima_init_template(void); void ima_init_template_list(void); int __init ima_init_digests(void);
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index e37c973a94c6..38b1c26479b3 100644
--- a/security/integrity/ima/ima_fs.c
+++ b/security/integrity/ima/ima_fs.c@@ -80,12 +80,13 @@ static const struct file_operations ima_measurements_count_ops = { /* returns pointer to hlist_node */ static void *ima_measurements_start(struct seq_file *m, loff_t *pos) { + struct ima_namespace *ns = get_current_ns(); loff_t l = *pos; struct ima_queue_entry *qe; /* we need a lock since pos could point beyond last element */ rcu_read_lock(); - list_for_each_entry_rcu(qe, &ima_measurements, later) { + list_for_each_entry_rcu(qe, &ns->ima_measurements, later) { if (!l--) { rcu_read_unlock(); return qe;
@@ -97,6 +98,7 @@ static void *ima_measurements_start(struct seq_file *m, loff_t *pos) static void *ima_measurements_next(struct seq_file *m, void *v, loff_t *pos) { + struct ima_namespace *ns = get_current_ns(); struct ima_queue_entry *qe = v; /* lock protects when reading beyond last element
@@ -107,7 +109,7 @@ static void *ima_measurements_next(struct seq_file *m, void *v, loff_t *pos) rcu_read_unlock(); (*pos)++; - return (&qe->later == &ima_measurements) ? NULL : qe; + return (&qe->later == &ns->ima_measurements) ? NULL : qe; } static void ima_measurements_stop(struct seq_file *m, void *v)
diff --git a/security/integrity/ima/ima_init_ima_ns.c b/security/integrity/ima/ima_init_ima_ns.c
index e13adc3287ed..57e46a10c001 100644
--- a/security/integrity/ima/ima_init_ima_ns.c
+++ b/security/integrity/ima/ima_init_ima_ns.c@@ -43,6 +43,11 @@ int ima_init_namespace(struct ima_namespace *ns) atomic_long_set(&ns->ima_htable.len, 0); atomic_long_set(&ns->ima_htable.violations, 0); memset(&ns->ima_htable.queue, 0, sizeof(ns->ima_htable.queue)); + INIT_LIST_HEAD(&ns->ima_measurements); + if (IS_ENABLED(CONFIG_IMA_KEXEC) && ns == &init_ima_ns) + ns->binary_runtime_size = 0; + else + ns->binary_runtime_size = ULONG_MAX; return 0; }
diff --git a/security/integrity/ima/ima_ns.c b/security/integrity/ima/ima_ns.c
index efbf7087a8ee..debe863364fd 100644
--- a/security/integrity/ima/ima_ns.c
+++ b/security/integrity/ima/ima_ns.c@@ -69,6 +69,7 @@ static void destroy_ima_ns(struct ima_namespace *ns) pr_debug("DESTROY ima_ns: 0x%p\n", ns); ima_free_policy_rules(ns); free_ns_status_cache(ns); + ima_free_measurements(ns); kmem_cache_free(imans_cachep, ns); }
diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c
index 373154039b91..f15f776918ec 100644
--- a/security/integrity/ima/ima_queue.c
+++ b/security/integrity/ima/ima_queue.c@@ -25,13 +25,6 @@ /* pre-allocated array of tpm_digest structures to extend a PCR */ static struct tpm_digest *digests; -LIST_HEAD(ima_measurements); /* list of all measurements */ -#ifdef CONFIG_IMA_KEXEC -static unsigned long binary_runtime_size; -#else -static unsigned long binary_runtime_size = ULONG_MAX; -#endif - /* mutex protects atomicity of extending measurement list * and extending the TPM PCR aggregate. Since tpm_extend can take * long (and the tpm driver uses a mutex), we can't use the spinlock.
@@ -107,7 +100,7 @@ static int ima_add_digest_entry(struct ima_namespace *ns, qe->entry = entry; INIT_LIST_HEAD(&qe->later); - list_add_tail_rcu(&qe->later, &ima_measurements); + list_add_tail_rcu(&qe->later, &ns->ima_measurements); atomic_long_inc(&ns->ima_htable.len); if (update_htable) {
@@ -116,12 +109,12 @@ static int ima_add_digest_entry(struct ima_namespace *ns, } else INIT_HLIST_NODE(&qe->hnext); - if (binary_runtime_size != ULONG_MAX) { + if (ns->binary_runtime_size != ULONG_MAX) { int size; size = get_binary_runtime_size(entry); - binary_runtime_size = (binary_runtime_size < ULONG_MAX - size) ? - binary_runtime_size + size : ULONG_MAX; + ns->binary_runtime_size = (ns->binary_runtime_size < ULONG_MAX - size) ? + ns->binary_runtime_size + size : ULONG_MAX; } return 0; }
@@ -131,12 +124,12 @@ static int ima_add_digest_entry(struct ima_namespace *ns, * entire binary_runtime_measurement list, including the ima_kexec_hdr * structure. */ -unsigned long ima_get_binary_runtime_size(void) +unsigned long ima_get_binary_runtime_size(struct ima_namespace *ns) { - if (binary_runtime_size >= (ULONG_MAX - sizeof(struct ima_kexec_hdr))) + if (ns->binary_runtime_size >= (ULONG_MAX - sizeof(struct ima_kexec_hdr))) return ULONG_MAX; else - return binary_runtime_size + sizeof(struct ima_kexec_hdr); + return ns->binary_runtime_size + sizeof(struct ima_kexec_hdr); } static int ima_pcr_extend(struct tpm_digest *digests_arg, int pcr)
@@ -217,6 +210,18 @@ int ima_restore_measurement_entry(struct ima_namespace *ns, return result; } +void ima_free_measurements(struct ima_namespace *ns) +{ + struct ima_queue_entry *qe, *tmp; + + list_for_each_entry_safe(qe, tmp, &ns->ima_measurements, later) { + list_del(&qe->later); + if (!hlist_unhashed(&qe->hnext)) + hlist_del(&qe->hnext); + kfree(qe); + } +} + int __init ima_init_digests(void) { u16 digest_size;
--
2.31.1