SELinux: return error codes on policy load failure

policy load failure always return EINVAL even if the failure was for some other reason (usually ENOMEM). This patch passes error codes back up the stack where they will make their way to userspace. This might help in debugging future problems with policy load.

Signed-off-by Eric Paris <[email protected]>

---

 security/selinux/ss/services.c |   37 ++++++++++++++++++++++---------------
 1 files changed, 22 insertions(+), 15 deletions(-)

security/selinux/ss/services.c +22 -15

index 0b44f5a..1de60ce 100644
@@ -1760,22 +1760,28 @@ int security_load_policy(void *data, size_t len)
 
 	if (!ss_initialized) {
 		avtab_cache_init();
-		if (policydb_read(&policydb, fp)) {
+		rc = policydb_read(&policydb, fp);
+		if (rc) {
 			avtab_cache_destroy();
-			return -EINVAL;
+			return rc;
 		}
-		if (selinux_set_mapping(&policydb, secclass_map,
-					&current_mapping,
-					&current_mapping_size)) {
+
+		rc = selinux_set_mapping(&policydb, secclass_map,
+					 &current_mapping,
+					 &current_mapping_size);
+		if (rc) {
 			policydb_destroy(&policydb);
 			avtab_cache_destroy();
-			return -EINVAL;
+			return rc;
 		}
-		if (policydb_load_isids(&policydb, &sidtab)) {
+
+		rc = policydb_load_isids(&policydb, &sidtab);
+		if (rc) {
 			policydb_destroy(&policydb);
 			avtab_cache_destroy();
-			return -EINVAL;
+			return rc;
 		}
+
 		security_load_policycaps();
 		ss_initialized = 1;
 		seqno = ++latest_granting;

@@ -1791,8 +1797,9 @@ int security_load_policy(void *data, size_t len)
 	sidtab_hash_eval(&sidtab, "sids");
 #endif
 
-	if (policydb_read(&newpolicydb, fp))
-		return -EINVAL;
+	rc = policydb_read(&newpolicydb, fp);
+	if (rc)
+		return rc;
 
 	/* If switching between different policy types, log MLS status */
 	if (policydb.mls_enabled && !newpolicydb.mls_enabled)

@@ -1807,8 +1814,8 @@ int security_load_policy(void *data, size_t len)
 		return rc;
 	}
 
-	if (selinux_set_mapping(&newpolicydb, secclass_map,
-				&map, &map_size))
+	rc = selinux_set_mapping(&newpolicydb, secclass_map, &map, &map_size);
+	if (rc)
 		goto err;
 
 	rc = security_preserve_bools(&newpolicydb);

@@ -1819,10 +1826,10 @@ int security_load_policy(void *data, size_t len)
 
 	/* Clone the SID table. */
 	sidtab_shutdown(&sidtab);
-	if (sidtab_map(&sidtab, clone_sid, &newsidtab)) {
-		rc = -ENOMEM;
+
+	rc = sidtab_map(&sidtab, clone_sid, &newsidtab);
+	if (rc)
 		goto err;
-	}
 
 	/*
 	 * Convert the internal representations of contexts

Note that policydb_read() internally has the same problem on some code paths, leading to the logic on the bad: path that defaults to EINVAL if not otherwise set.

policy load failure always return EINVAL even if the failure was for some other reason (usually ENOMEM). This patch passes error codes back up the stack where they will make their way to userspace. This might help in debugging future problems with policy load.

Signed-off-by Eric Paris <[email protected]>