[PATCH v37 12/33] LSM: Use lsmblob in security_inode_getsecid
From: Casey Schaufler
Date: Mon Jun 27 2022 - 21:05:45 EST
Change the security_inode_getsecid() interface to fill in a
lsmblob structure instead of a u32 secid. This allows for its
callers to gather data from all registered LSMs. Data is provided
for IMA and audit.
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Reviewed-by: John Johansen <john.johansen@xxxxxxxxxxxxx>
Acked-by: Stephen Smalley <stephen.smalley.work@xxxxxxxxx>
Acked-by: Paul Moore <paul@xxxxxxxxxxxxxx>
Signed-off-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx>
Cc: linux-integrity@xxxxxxxxxxxxxxx
Cc: linux-audit@xxxxxxxxxx
---
include/linux/security.h | 13 +++++++------
kernel/auditsc.c | 6 +++++-
security/integrity/ima/ima_policy.c | 9 +++++----
security/security.c | 19 +++++++++++++------
4 files changed, 30 insertions(+), 17 deletions(-)
diff --git a/include/linux/security.h b/include/linux/security.h
index ce4a4af362f3..a478faa6124e 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -476,7 +476,7 @@ int security_inode_getsecurity(struct user_namespace *mnt_userns,
void **buffer, bool alloc);
int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags);
int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size);
-void security_inode_getsecid(struct inode *inode, u32 *secid);
+void security_inode_getsecid(struct inode *inode, struct lsmblob *blob);
int security_inode_copy_up(struct dentry *src, struct cred **new);
int security_inode_copy_up_xattr(const char *name);
int security_kernfs_init_security(struct kernfs_node *kn_dir,
@@ -1022,9 +1022,10 @@ static inline int security_inode_listsecurity(struct inode *inode, char *buffer,
return 0;
}
-static inline void security_inode_getsecid(struct inode *inode, u32 *secid)
+static inline void security_inode_getsecid(struct inode *inode,
+ struct lsmblob *blob)
{
- *secid = 0;
+ lsmblob_init(blob, 0);
}
static inline int security_inode_copy_up(struct dentry *src, struct cred **new)
@@ -2034,8 +2035,8 @@ static inline void security_audit_rule_free(struct audit_lsm_rules *lsmrules)
#if defined(CONFIG_IMA_LSM_RULES) && defined(CONFIG_SECURITY)
int ima_filter_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule,
int lsmslot);
-int ima_filter_rule_match(u32 secid, u32 field, u32 op, void *lsmrule,
- int lsmslot);
+int ima_filter_rule_match(struct lsmblob *blob, u32 field, u32 op,
+ void *lsmrule, int lsmslot);
void ima_filter_rule_free(void *lsmrule, int lsmslot);
#else
@@ -2046,7 +2047,7 @@ static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr,
return 0;
}
-static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op,
+static inline int ima_filter_rule_match(struct lsmblob *blob, u32 field, u32 op,
void *lsmrule, int lsmslot)
{
return 0;
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index e5530bbfc83b..1d223176285b 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2306,13 +2306,17 @@ static void audit_copy_inode(struct audit_names *name,
const struct dentry *dentry,
struct inode *inode, unsigned int flags)
{
+ struct lsmblob blob;
+
name->ino = inode->i_ino;
name->dev = inode->i_sb->s_dev;
name->mode = inode->i_mode;
name->uid = inode->i_uid;
name->gid = inode->i_gid;
name->rdev = inode->i_rdev;
- security_inode_getsecid(inode, &name->osid);
+ security_inode_getsecid(inode, &blob);
+ /* scaffolding until osid is updated */
+ name->osid = lsmblob_first(&blob);
if (flags & AUDIT_INODE_NOEVAL) {
name->fcap_ver = -1;
return;
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 5c2bc6782e17..593b0ba51b6e 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -636,7 +636,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule,
return false;
for (i = 0; i < MAX_LSM_RULES; i++) {
int rc = 0;
- u32 osid;
+ struct lsmblob lsmdata;
if (!rule->lsm[i].rule) {
if (!rule->lsm[i].args_p)
@@ -648,8 +648,9 @@ static bool ima_match_rules(struct ima_rule_entry *rule,
case LSM_OBJ_USER:
case LSM_OBJ_ROLE:
case LSM_OBJ_TYPE:
- security_inode_getsecid(inode, &osid);
- rc = ima_filter_rule_match(osid, rule->lsm[i].type,
+ security_inode_getsecid(inode, &lsmdata);
+ rc = ima_filter_rule_match(&lsmdata,
+ rule->lsm[i].type,
Audit_equal,
rule->lsm[i].rule,
rule->lsm[i].rules_lsm);
@@ -657,7 +658,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule,
case LSM_SUBJ_USER:
case LSM_SUBJ_ROLE:
case LSM_SUBJ_TYPE:
- rc = ima_filter_rule_match(lsmblob_first(blob),
+ rc = ima_filter_rule_match(blob,
rule->lsm[i].type,
Audit_equal,
rule->lsm[i].rule,
diff --git a/security/security.c b/security/security.c
index 1a4741178944..ad1080e01ba8 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1560,9 +1560,16 @@ int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer
}
EXPORT_SYMBOL(security_inode_listsecurity);
-void security_inode_getsecid(struct inode *inode, u32 *secid)
+void security_inode_getsecid(struct inode *inode, struct lsmblob *blob)
{
- call_void_hook(inode_getsecid, inode, secid);
+ struct security_hook_list *hp;
+
+ lsmblob_init(blob, 0);
+ hlist_for_each_entry(hp, &security_hook_heads.inode_getsecid, list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ hp->hook.inode_getsecid(inode, &blob->secid[hp->lsmid->slot]);
+ }
}
int security_inode_copy_up(struct dentry *src, struct cred **new)
@@ -2804,15 +2811,15 @@ void ima_filter_rule_free(void *lsmrule, int lsmslot)
}
}
-int ima_filter_rule_match(u32 secid, u32 field, u32 op, void *lsmrule,
- int lsmslot)
+int ima_filter_rule_match(struct lsmblob *blob, u32 field, u32 op,
+ void *lsmrule, int lsmslot)
{
struct security_hook_list *hp;
hlist_for_each_entry(hp, &security_hook_heads.audit_rule_match, list)
if (hp->lsmid->slot == lsmslot)
- return hp->hook.audit_rule_match(secid, field, op,
- lsmrule);
+ return hp->hook.audit_rule_match(blob->secid[lsmslot],
+ field, op, lsmrule);
return 0;
}
--
2.36.1