[PATCH v4 11/13] Audit: Change context data from secid to lsm_prop

From: Casey Schaufler
Date: Wed Oct 09 2024 - 13:36:31 EST


Change the LSM data stored in the audit transactions from a secid
to an LSM prop. This is done in struct audit_context and struct
audit_aux_data_pids. Several cases of scaffolding can be removed.

Signed-off-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx>
---
kernel/audit.h | 2 +-
kernel/auditfilter.c | 1 -
kernel/auditsc.c | 31 ++++++++++++-------------------
3 files changed, 13 insertions(+), 21 deletions(-)

diff --git a/kernel/audit.h b/kernel/audit.h
index 8e6f886a83a4..0211cb307d30 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -144,7 +144,7 @@ struct audit_context {
kuid_t target_auid;
kuid_t target_uid;
unsigned int target_sessionid;
- u32 target_sid;
+ struct lsm_prop target_ref;
char target_comm[TASK_COMM_LEN];

struct audit_tree_refs *trees, *first_trees;
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index a7de3dabe6e1..bceb9f58a09e 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -1370,7 +1370,6 @@ int audit_filter(int msgtype, unsigned int listtype)
case AUDIT_SUBJ_SEN:
case AUDIT_SUBJ_CLR:
if (f->lsm_rule) {
- /* scaffolding */
security_current_getlsmprop_subj(&prop);
result = security_audit_rule_match(
&prop, f->type, f->op,
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 53fbd2e5d934..f28fd513d047 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -100,7 +100,7 @@ struct audit_aux_data_pids {
kuid_t target_auid[AUDIT_AUX_PIDS];
kuid_t target_uid[AUDIT_AUX_PIDS];
unsigned int target_sessionid[AUDIT_AUX_PIDS];
- u32 target_sid[AUDIT_AUX_PIDS];
+ struct lsm_prop target_ref[AUDIT_AUX_PIDS];
char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
int pid_count;
};
@@ -1019,7 +1019,7 @@ static void audit_reset_context(struct audit_context *ctx)
ctx->target_pid = 0;
ctx->target_auid = ctx->target_uid = KUIDT_INIT(0);
ctx->target_sessionid = 0;
- ctx->target_sid = 0;
+ lsmprop_init(&ctx->target_ref);
ctx->target_comm[0] = '\0';
unroll_tree_refs(ctx, NULL, 0);
WARN_ON(!list_empty(&ctx->killed_trees));
@@ -1093,8 +1093,9 @@ static inline void audit_free_context(struct audit_context *context)
}

static int audit_log_pid_context(struct audit_context *context, pid_t pid,
- kuid_t auid, kuid_t uid, unsigned int sessionid,
- u32 sid, char *comm)
+ kuid_t auid, kuid_t uid,
+ unsigned int sessionid, struct lsm_prop *prop,
+ char *comm)
{
struct audit_buffer *ab;
char *ctx = NULL;
@@ -1108,8 +1109,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
from_kuid(&init_user_ns, auid),
from_kuid(&init_user_ns, uid), sessionid);
- if (sid) {
- if (security_secid_to_secctx(sid, &ctx, &len)) {
+ if (lsmprop_is_set(prop)) {
+ if (security_lsmprop_to_secctx(prop, &ctx, &len)) {
audit_log_format(ab, " obj=(none)");
rc = 1;
} else {
@@ -1778,7 +1779,7 @@ static void audit_log_exit(void)
axs->target_auid[i],
axs->target_uid[i],
axs->target_sessionid[i],
- axs->target_sid[i],
+ &axs->target_ref[i],
axs->target_comm[i]))
call_panic = 1;
}
@@ -1787,7 +1788,7 @@ static void audit_log_exit(void)
audit_log_pid_context(context, context->target_pid,
context->target_auid, context->target_uid,
context->target_sessionid,
- context->target_sid, context->target_comm))
+ &context->target_ref, context->target_comm))
call_panic = 1;

if (context->pwd.dentry && context->pwd.mnt) {
@@ -2722,15 +2723,12 @@ int __audit_sockaddr(int len, void *a)
void __audit_ptrace(struct task_struct *t)
{
struct audit_context *context = audit_context();
- struct lsm_prop prop;

context->target_pid = task_tgid_nr(t);
context->target_auid = audit_get_loginuid(t);
context->target_uid = task_uid(t);
context->target_sessionid = audit_get_sessionid(t);
- security_task_getlsmprop_obj(t, &prop);
- /* scaffolding */
- context->target_sid = prop.scaffold.secid;
+ security_task_getlsmprop_obj(t, &context->target_ref);
memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
}

@@ -2746,7 +2744,6 @@ int audit_signal_info_syscall(struct task_struct *t)
struct audit_aux_data_pids *axp;
struct audit_context *ctx = audit_context();
kuid_t t_uid = task_uid(t);
- struct lsm_prop prop;

if (!audit_signals || audit_dummy_context())
return 0;
@@ -2758,9 +2755,7 @@ int audit_signal_info_syscall(struct task_struct *t)
ctx->target_auid = audit_get_loginuid(t);
ctx->target_uid = t_uid;
ctx->target_sessionid = audit_get_sessionid(t);
- security_task_getlsmprop_obj(t, &prop);
- /* scaffolding */
- ctx->target_sid = prop.scaffold.secid;
+ security_task_getlsmprop_obj(t, &ctx->target_ref);
memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
return 0;
}
@@ -2781,9 +2776,7 @@ int audit_signal_info_syscall(struct task_struct *t)
axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
axp->target_uid[axp->pid_count] = t_uid;
axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
- security_task_getlsmprop_obj(t, &prop);
- /* scaffolding */
- axp->target_sid[axp->pid_count] = prop.scaffold.secid;
+ security_task_getlsmprop_obj(t, &axp->target_ref[axp->pid_count]);
memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
axp->pid_count++;

--
2.46.0