2022-09-27 20:39:31

by Casey Schaufler

[permalink] [raw]
Subject: [PATCH v38 09/39] LSM: Add the lsmblob data structure.

When more than one security module is exporting data to
audit and networking sub-systems a single 32 bit integer
is no longer sufficient to represent the data. Add a
structure to be used instead.

The lsmblob structure is currently an array of
u32 "secids". There is an entry for each of the security
modules built into the system that would use secids if
active. The system assigns the module a "slot" when it
registers hooks. If modules are compiled in but not
registered there will be unused slots. The slot number
is added to the lsm_id structure.

The audit rules data is expanded to use an array of
security module data rather than a single instance.
A new structure audit_lsm_rules is defined to avoid the
confusion which commonly accompanies the use of
void ** parameters.

Signed-off-by: Casey Schaufler <[email protected]>
---
include/linux/audit.h | 9 ++++-
include/linux/lsm_hooks.h | 1 +
include/linux/security.h | 75 +++++++++++++++++++++++++++++++++---
kernel/auditfilter.c | 23 +++++------
kernel/auditsc.c | 17 ++++----
security/apparmor/lsm.c | 1 +
security/bpf/hooks.c | 1 +
security/commoncap.c | 1 +
security/landlock/setup.c | 1 +
security/loadpin/loadpin.c | 1 +
security/lockdown/lockdown.c | 1 +
security/safesetid/lsm.c | 1 +
security/security.c | 70 ++++++++++++++++++++++++++++++---
security/selinux/hooks.c | 1 +
security/smack/smack_lsm.c | 1 +
security/tomoyo/tomoyo.c | 1 +
security/yama/yama_lsm.c | 1 +
17 files changed, 171 insertions(+), 35 deletions(-)

diff --git a/include/linux/audit.h b/include/linux/audit.h
index 3608992848d3..edb919722448 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -11,6 +11,7 @@

#include <linux/sched.h>
#include <linux/ptrace.h>
+#include <linux/security.h>
#include <linux/audit_arch.h>
#include <uapi/linux/audit.h>
#include <uapi/linux/netfilter/nf_tables.h>
@@ -59,6 +60,10 @@ struct audit_krule {
/* Flag to indicate legacy AUDIT_LOGINUID unset usage */
#define AUDIT_LOGINUID_LEGACY 0x1

+struct audit_lsm_rules {
+ void *rule[LSMBLOB_ENTRIES];
+};
+
struct audit_field {
u32 type;
union {
@@ -66,8 +71,8 @@ struct audit_field {
kuid_t uid;
kgid_t gid;
struct {
- char *lsm_str;
- void *lsm_rule;
+ char *lsm_str;
+ struct audit_lsm_rules lsm_rules;
};
};
u32 op;
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index b266d0826278..db251a51d4cb 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -1605,6 +1605,7 @@ struct lsm_id {
const char *lsm; /* Name of the LSM */
int id; /* LSM ID */
int features; /* Set of LSM features */
+ int slot; /* Slot in lsmblob if allocated */
};

/*
diff --git a/include/linux/security.h b/include/linux/security.h
index fe3273a6498f..c1f8b33e7c27 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -39,6 +39,7 @@ struct kernel_siginfo;
struct sembuf;
struct kern_ipc_perm;
struct audit_context;
+struct audit_lsm_rules;
struct super_block;
struct inode;
struct dentry;
@@ -153,6 +154,66 @@ extern const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX+1];
extern int lsm_id;
extern struct lsm_id *lsm_idlist[];

+/*
+ * Data exported by the security modules
+ *
+ * Any LSM that provides secid or secctx based hooks must be included.
+ */
+#define LSMBLOB_ENTRIES ( \
+ (IS_ENABLED(CONFIG_SECURITY_SELINUX) ? 1 : 0) + \
+ (IS_ENABLED(CONFIG_SECURITY_SMACK) ? 1 : 0) + \
+ (IS_ENABLED(CONFIG_SECURITY_APPARMOR) ? 1 : 0) + \
+ (IS_ENABLED(CONFIG_BPF_LSM) ? 1 : 0))
+
+struct lsmblob {
+ u32 secid[LSMBLOB_ENTRIES];
+};
+
+#define LSMBLOB_INVALID -1 /* Not a valid LSM slot number */
+#define LSMBLOB_NEEDED -2 /* Slot requested on initialization */
+#define LSMBLOB_NOT_NEEDED -3 /* Slot not requested */
+
+/**
+ * lsmblob_init - initialize a lsmblob structure
+ * @blob: Pointer to the data to initialize
+ * @secid: The initial secid value
+ *
+ * Set all secid for all modules to the specified value.
+ */
+static inline void lsmblob_init(struct lsmblob *blob, u32 secid)
+{
+ int i;
+
+ for (i = 0; i < LSMBLOB_ENTRIES; i++)
+ blob->secid[i] = secid;
+}
+
+/**
+ * lsmblob_is_set - report if there is a value in the lsmblob
+ * @blob: Pointer to the exported LSM data
+ *
+ * Returns true if there is a secid set, false otherwise
+ */
+static inline bool lsmblob_is_set(struct lsmblob *blob)
+{
+ const struct lsmblob empty = {};
+
+ return !!memcmp(blob, &empty, sizeof(*blob));
+}
+
+/**
+ * lsmblob_equal - report if the two lsmblob's are equal
+ * @bloba: Pointer to one LSM data
+ * @blobb: Pointer to the other LSM data
+ *
+ * Returns true if all entries in the two are equal, false otherwise
+ */
+static inline bool lsmblob_equal(const struct lsmblob *bloba,
+ const struct lsmblob *blobb)
+{
+ return !memcmp(bloba, blobb, sizeof(*bloba));
+}
+
/* These functions are in security/commoncap.c */
extern int cap_capable(const struct cred *cred, struct user_namespace *ns,
int cap, unsigned int opts);
@@ -1914,15 +1975,17 @@ static inline int security_key_getsecurity(struct key *key, char **_buffer)

#ifdef CONFIG_AUDIT
#ifdef CONFIG_SECURITY
-int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule);
+int security_audit_rule_init(u32 field, u32 op, char *rulestr,
+ struct audit_lsm_rules *lsmrules);
int security_audit_rule_known(struct audit_krule *krule);
-int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule);
-void security_audit_rule_free(void *lsmrule);
+int security_audit_rule_match(u32 secid, u32 field, u32 op,
+ struct audit_lsm_rules *lsmrules);
+void security_audit_rule_free(struct audit_lsm_rules *lsmrules);

#else

static inline int security_audit_rule_init(u32 field, u32 op, char *rulestr,
- void **lsmrule)
+ struct audit_lsm_rules *lsmrules)
{
return 0;
}
@@ -1933,12 +1996,12 @@ static inline int security_audit_rule_known(struct audit_krule *krule)
}

static inline int security_audit_rule_match(u32 secid, u32 field, u32 op,
- void *lsmrule)
+ struct audit_lsm_rules *lsmrules)
{
return 0;
}

-static inline void security_audit_rule_free(void *lsmrule)
+static inline void security_audit_rule_free(struct audit_lsm_rules *lsmrules)
{ }

#endif /* CONFIG_SECURITY */
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 42d99896e7a6..de75bd6ad866 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -76,7 +76,7 @@ static void audit_free_lsm_field(struct audit_field *f)
case AUDIT_OBJ_LEV_LOW:
case AUDIT_OBJ_LEV_HIGH:
kfree(f->lsm_str);
- security_audit_rule_free(f->lsm_rule);
+ security_audit_rule_free(&f->lsm_rules);
}
}

@@ -529,7 +529,7 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
entry->rule.buflen += f_val;
f->lsm_str = str;
err = security_audit_rule_init(f->type, f->op, str,
- (void **)&f->lsm_rule);
+ &f->lsm_rules);
/* Keep currently invalid fields around in case they
* become valid after a policy reload. */
if (err == -EINVAL) {
@@ -782,7 +782,7 @@ static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b)
return 0;
}

-/* Duplicate LSM field information. The lsm_rule is opaque, so must be
+/* Duplicate LSM field information. The lsm_rules is opaque, so must be
* re-initialized. */
static inline int audit_dupe_lsm_field(struct audit_field *df,
struct audit_field *sf)
@@ -796,9 +796,9 @@ static inline int audit_dupe_lsm_field(struct audit_field *df,
return -ENOMEM;
df->lsm_str = lsm_str;

- /* our own (refreshed) copy of lsm_rule */
+ /* our own (refreshed) copy of lsm_rules */
ret = security_audit_rule_init(df->type, df->op, df->lsm_str,
- (void **)&df->lsm_rule);
+ &df->lsm_rules);
/* Keep currently invalid fields around in case they
* become valid after a policy reload. */
if (ret == -EINVAL) {
@@ -850,7 +850,7 @@ struct audit_entry *audit_dupe_rule(struct audit_krule *old)
new->tree = old->tree;
memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount);

- /* deep copy this information, updating the lsm_rule fields, because
+ /* deep copy this information, updating the lsm_rules fields, because
* the originals will all be freed when the old rule is freed. */
for (i = 0; i < fcount; i++) {
switch (new->fields[i].type) {
@@ -1367,10 +1367,11 @@ int audit_filter(int msgtype, unsigned int listtype)
case AUDIT_SUBJ_TYPE:
case AUDIT_SUBJ_SEN:
case AUDIT_SUBJ_CLR:
- if (f->lsm_rule) {
+ if (f->lsm_str) {
security_current_getsecid_subj(&sid);
result = security_audit_rule_match(sid,
- f->type, f->op, f->lsm_rule);
+ f->type, f->op,
+ &f->lsm_rules);
}
break;
case AUDIT_EXE:
@@ -1397,7 +1398,7 @@ int audit_filter(int msgtype, unsigned int listtype)
return ret;
}

-static int update_lsm_rule(struct audit_krule *r)
+static int update_lsm_rules(struct audit_krule *r)
{
struct audit_entry *entry = container_of(r, struct audit_entry, rule);
struct audit_entry *nentry;
@@ -1429,7 +1430,7 @@ static int update_lsm_rule(struct audit_krule *r)
return err;
}

-/* This function will re-initialize the lsm_rule field of all applicable rules.
+/* This function will re-initialize the lsm_rules field of all applicable rules.
* It will traverse the filter lists serarching for rules that contain LSM
* specific filter fields. When such a rule is found, it is copied, the
* LSM field is re-initialized, and the old rule is replaced with the
@@ -1444,7 +1445,7 @@ int audit_update_lsm_rules(void)

for (i = 0; i < AUDIT_NR_FILTERS; i++) {
list_for_each_entry_safe(r, n, &audit_rules_list[i], list) {
- int res = update_lsm_rule(r);
+ int res = update_lsm_rules(r);
if (!err)
err = res;
}
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 79a5da1bc5bb..482805f6ea68 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -664,7 +664,7 @@ static int audit_filter_rules(struct task_struct *tsk,
match for now to avoid losing information that
may be wanted. An error message will also be
logged upon error */
- if (f->lsm_rule) {
+ if (f->lsm_str) {
if (need_sid) {
/* @tsk should always be equal to
* @current with the exception of
@@ -679,8 +679,7 @@ static int audit_filter_rules(struct task_struct *tsk,
need_sid = 0;
}
result = security_audit_rule_match(sid, f->type,
- f->op,
- f->lsm_rule);
+ f->op, &f->lsm_rules);
}
break;
case AUDIT_OBJ_USER:
@@ -690,21 +689,19 @@ static int audit_filter_rules(struct task_struct *tsk,
case AUDIT_OBJ_LEV_HIGH:
/* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
also applies here */
- if (f->lsm_rule) {
+ if (f->lsm_str) {
/* Find files that match */
if (name) {
result = security_audit_rule_match(
name->osid,
f->type,
f->op,
- f->lsm_rule);
+ &f->lsm_rules);
} else if (ctx) {
list_for_each_entry(n, &ctx->names_list, list) {
if (security_audit_rule_match(
- n->osid,
- f->type,
- f->op,
- f->lsm_rule)) {
+ n->osid, f->type, f->op,
+ &f->lsm_rules)) {
++result;
break;
}
@@ -715,7 +712,7 @@ static int audit_filter_rules(struct task_struct *tsk,
break;
if (security_audit_rule_match(ctx->ipc.osid,
f->type, f->op,
- f->lsm_rule))
+ &f->lsm_rules))
++result;
}
break;
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index caad42a0c913..25423a3aa572 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -1190,6 +1190,7 @@ static struct lsm_id apparmor_lsmid __lsm_ro_after_init = {
.lsm = "apparmor",
.id = LSM_ID_APPARMOR,
.features = LSM_ATTR_CURRENT | LSM_ATTR_PREV | LSM_ATTR_EXEC,
+ .slot = LSMBLOB_NEEDED,
};

static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
diff --git a/security/bpf/hooks.c b/security/bpf/hooks.c
index c462fc41dd57..d92a21ca3d1b 100644
--- a/security/bpf/hooks.c
+++ b/security/bpf/hooks.c
@@ -23,6 +23,7 @@ static struct security_hook_list bpf_lsm_hooks[] __lsm_ro_after_init = {
struct lsm_id bpf_lsmid __lsm_ro_after_init = {
.lsm = "bpf",
.id = LSM_ID_BPF,
+ .slot = LSMBLOB_NEEDED,
};

static int __init bpf_lsm_init(void)
diff --git a/security/commoncap.c b/security/commoncap.c
index 4e9b140159d8..29c7642a9fb5 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -1450,6 +1450,7 @@ int cap_mmap_file(struct file *file, unsigned long reqprot,
static struct lsm_id capability_lsmid __lsm_ro_after_init = {
.lsm = "capability",
.id = LSM_ID_CAPABILITY,
+ .slot = LSMBLOB_NOT_NEEDED,
};

static struct security_hook_list capability_hooks[] __lsm_ro_after_init = {
diff --git a/security/landlock/setup.c b/security/landlock/setup.c
index 1242c61c9de4..adbe941370f3 100644
--- a/security/landlock/setup.c
+++ b/security/landlock/setup.c
@@ -27,6 +27,7 @@ struct lsm_blob_sizes landlock_blob_sizes __lsm_ro_after_init = {
struct lsm_id landlock_lsmid __lsm_ro_after_init = {
.lsm = LANDLOCK_NAME,
.id = LSM_ID_LANDLOCK,
+ .slot = LSMBLOB_NOT_NEEDED,
};

static int __init landlock_init(void)
diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c
index 276c8a7cd6fe..c3f5678b92c4 100644
--- a/security/loadpin/loadpin.c
+++ b/security/loadpin/loadpin.c
@@ -199,6 +199,7 @@ static int loadpin_load_data(enum kernel_load_data_id id, bool contents)
static struct lsm_id loadpin_lsmid __lsm_ro_after_init = {
.lsm = "loadpin",
.id = LSM_ID_LOADPIN,
+ .slot = LSMBLOB_NOT_NEEDED,
};

static struct security_hook_list loadpin_hooks[] __lsm_ro_after_init = {
diff --git a/security/lockdown/lockdown.c b/security/lockdown/lockdown.c
index 3d3347f3dbd1..1f87e8d43387 100644
--- a/security/lockdown/lockdown.c
+++ b/security/lockdown/lockdown.c
@@ -79,6 +79,7 @@ static struct security_hook_list lockdown_hooks[] __lsm_ro_after_init = {
static struct lsm_id lockdown_lsmid __lsm_ro_after_init = {
.lsm = "lockdown",
.id = LSM_ID_LOCKDOWN,
+ .slot = LSMBLOB_NOT_NEEDED,
};

static int __init lockdown_lsm_init(void)
diff --git a/security/safesetid/lsm.c b/security/safesetid/lsm.c
index 88002731e603..bddf9a28c270 100644
--- a/security/safesetid/lsm.c
+++ b/security/safesetid/lsm.c
@@ -265,6 +265,7 @@ static int safesetid_task_fix_setgroups(struct cred *new, const struct cred *old
static struct lsm_id safesetid_lsmid __lsm_ro_after_init = {
.lsm = "safesetid",
.id = LSM_ID_SAFESETID,
+ .slot = LSMBLOB_NOT_NEEDED,
};

static struct security_hook_list safesetid_security_hooks[] = {
diff --git a/security/security.c b/security/security.c
index 7a604a74716a..b837500cb3dc 100644
--- a/security/security.c
+++ b/security/security.c
@@ -354,6 +354,7 @@ static void __init ordered_lsm_init(void)
init_debug("sock blob size = %d\n", blob_sizes.lbs_sock);
init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
init_debug("task blob size = %d\n", blob_sizes.lbs_task);
+ init_debug("lsmblob size = %zu\n", sizeof(struct lsmblob));

/*
* Create any kmem_caches needed for blobs
@@ -481,6 +482,11 @@ static int lsm_append(const char *new, char **result)
return 0;
}

+/*
+ * Current index to use while initializing the lsmblob secid list.
+ */
+static int lsm_slot __lsm_ro_after_init;
+
/**
* security_add_hooks - Add a modules hooks to the hook lists.
* @hooks: the hooks to add
@@ -488,6 +494,8 @@ static int lsm_append(const char *new, char **result)
* @lsmid: the identification information for the security module
*
* Each LSM has to register its hooks with the infrastructure.
+ * If the LSM is using hooks that export secids allocate a slot
+ * for it in the lsmblob.
*/
void __init security_add_hooks(struct security_hook_list *hooks, int count,
struct lsm_id *lsmid)
@@ -504,6 +512,16 @@ void __init security_add_hooks(struct security_hook_list *hooks, int count,
if (lsm_id > LSMID_ENTRIES)
panic("%s Too many LSMs registered.\n", __func__);

+ WARN_ON(!lsmid->slot || !lsmid->id);
+
+ if (lsmid->slot == LSMBLOB_NEEDED) {
+ if (lsm_slot >= LSMBLOB_ENTRIES)
+ panic("%s Too many LSMs registered.\n", __func__);
+ lsmid->slot = lsm_slot++;
+ init_debug("%s assigned lsmblob slot %d\n", lsmid->lsm,
+ lsmid->slot);
+ }
+
for (i = 0; i < count; i++) {
hooks[i].lsmid = lsmid;
hlist_add_tail_rcu(&hooks[i].list, hooks[i].head);
@@ -2616,9 +2634,27 @@ int security_key_getsecurity(struct key *key, char **_buffer)

#ifdef CONFIG_AUDIT

-int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule)
+int security_audit_rule_init(u32 field, u32 op, char *rulestr,
+ struct audit_lsm_rules *lsmrules)
{
- return call_int_hook(audit_rule_init, 0, field, op, rulestr, lsmrule);
+ struct security_hook_list *hp;
+ bool one_is_good = false;
+ int rc = 0;
+ int trc;
+
+ hlist_for_each_entry(hp, &security_hook_heads.audit_rule_init, list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ trc = hp->hook.audit_rule_init(field, op, rulestr,
+ &lsmrules->rule[hp->lsmid->slot]);
+ if (trc == 0)
+ one_is_good = true;
+ else
+ rc = trc;
+ }
+ if (one_is_good)
+ return 0;
+ return rc;
}

int security_audit_rule_known(struct audit_krule *krule)
@@ -2626,14 +2662,36 @@ int security_audit_rule_known(struct audit_krule *krule)
return call_int_hook(audit_rule_known, 0, krule);
}

-void security_audit_rule_free(void *lsmrule)
+void security_audit_rule_free(struct audit_lsm_rules *lsmrules)
{
- call_void_hook(audit_rule_free, lsmrule);
+ struct security_hook_list *hp;
+
+ hlist_for_each_entry(hp, &security_hook_heads.audit_rule_free, list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ if (lsmrules->rule[hp->lsmid->slot] == NULL)
+ continue;
+ hp->hook.audit_rule_free(lsmrules->rule[hp->lsmid->slot]);
+ }
}

-int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule)
+int security_audit_rule_match(u32 secid, u32 field, u32 op,
+ struct audit_lsm_rules *lsmrules)
{
- return call_int_hook(audit_rule_match, 0, secid, field, op, lsmrule);
+ struct security_hook_list *hp;
+ int rc;
+
+ hlist_for_each_entry(hp, &security_hook_heads.audit_rule_match, list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ if (lsmrules->rule[hp->lsmid->slot] == NULL)
+ continue;
+ rc = hp->hook.audit_rule_match(secid, field, op,
+ &lsmrules->rule[hp->lsmid->slot]);
+ if (rc)
+ return rc;
+ }
+ return 0;
}
#endif /* CONFIG_AUDIT */

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 25cc17bdd33c..cf89ccaa018d 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -7014,6 +7014,7 @@ static struct lsm_id selinux_lsmid __lsm_ro_after_init = {
.id = LSM_ID_SELINUX,
.features = LSM_ATTR_CURRENT | LSM_ATTR_EXEC | LSM_ATTR_FSCREATE |
LSM_ATTR_KEYCREATE | LSM_ATTR_PREV | LSM_ATTR_SOCKCREATE,
+ .slot = LSMBLOB_NEEDED,
};

/*
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index c399ed799ceb..fbcf20ef1394 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -4773,6 +4773,7 @@ static struct lsm_id smack_lsmid __lsm_ro_after_init = {
.lsm = "smack",
.id = LSM_ID_SMACK,
.features = LSM_ATTR_CURRENT,
+ .slot = LSMBLOB_NEEDED,
};

static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c
index 71eab206ba6e..78b11332eb5b 100644
--- a/security/tomoyo/tomoyo.c
+++ b/security/tomoyo/tomoyo.c
@@ -534,6 +534,7 @@ static void tomoyo_task_free(struct task_struct *task)
static struct lsm_id tomoyo_lsmid __lsm_ro_after_init = {
.lsm = "tomoyo",
.id = LSM_ID_TOMOYO,
+ .slot = LSMBLOB_NOT_NEEDED,
};

/*
diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c
index b178d74bb00b..e11dd71553f4 100644
--- a/security/yama/yama_lsm.c
+++ b/security/yama/yama_lsm.c
@@ -425,6 +425,7 @@ static int yama_ptrace_traceme(struct task_struct *parent)
static struct lsm_id yama_lsmid __lsm_ro_after_init = {
.lsm = "yama",
.id = LSM_ID_YAMA,
+ .slot = LSMBLOB_NOT_NEEDED,
};

static struct security_hook_list yama_hooks[] __lsm_ro_after_init = {
--
2.37.3


2022-10-12 22:00:47

by Mickaël Salaün

[permalink] [raw]
Subject: Re: [PATCH v38 09/39] LSM: Add the lsmblob data structure.


On 27/09/2022 21:53, Casey Schaufler wrote:
> When more than one security module is exporting data to
> audit and networking sub-systems a single 32 bit integer
> is no longer sufficient to represent the data. Add a
> structure to be used instead.
>
> The lsmblob structure is currently an array of
> u32 "secids". There is an entry for each of the security
> modules built into the system that would use secids if
> active. The system assigns the module a "slot" when it
> registers hooks. If modules are compiled in but not
> registered there will be unused slots. The slot number
> is added to the lsm_id structure.
>
> The audit rules data is expanded to use an array of
> security module data rather than a single instance.
> A new structure audit_lsm_rules is defined to avoid the
> confusion which commonly accompanies the use of
> void ** parameters.
>
> Signed-off-by: Casey Schaufler <[email protected]>
> ---

[...]

> diff --git a/security/landlock/setup.c b/security/landlock/setup.c
> index 1242c61c9de4..adbe941370f3 100644
> --- a/security/landlock/setup.c
> +++ b/security/landlock/setup.c
> @@ -27,6 +27,7 @@ struct lsm_blob_sizes landlock_blob_sizes __lsm_ro_after_init = {
> struct lsm_id landlock_lsmid __lsm_ro_after_init = {
> .lsm = LANDLOCK_NAME,
> .id = LSM_ID_LANDLOCK,
> + .slot = LSMBLOB_NOT_NEEDED,

Please only use one space after ".slot"