TOMOYO: Remove next_domain from tomoyo_find_next_domain().

We can update bprm->cred->security inside tomoyo_find_next_domain().

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>

security/tomoyo/domain.c

@@ -786,13 +786,11 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char *
 /**
  * tomoyo_find_next_domain - Find a domain.
  *
- * @bprm:           Pointer to "struct linux_binprm".
- * @next_domain:    Pointer to pointer to "struct tomoyo_domain_info".
+ * @bprm: Pointer to "struct linux_binprm".
  *
  * Returns 0 on success, negative value otherwise.
  */
-int tomoyo_find_next_domain(struct linux_binprm *bprm,
-			    struct tomoyo_domain_info **next_domain)
+int tomoyo_find_next_domain(struct linux_binprm *bprm)
 {
 	/*
 	 * This function assumes that the size of buffer returned by
@@ -914,9 +912,11 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm,
 		tomoyo_set_domain_flag(old_domain, false,
 				       TOMOYO_DOMAIN_FLAGS_TRANSITION_FAILED);
  out:
+	if (!domain)
+		domain = old_domain;
+	bprm->cred->security = domain;
 	tomoyo_free(real_program_name);
 	tomoyo_free(symlink_program_name);
-	*next_domain = domain ? domain : old_domain;
 	tomoyo_free(tmp);
 	return retval;
 }

security/tomoyo/tomoyo.c

@@ -61,14 +61,8 @@ static int tomoyo_bprm_check_security(struct linux_binprm *bprm)
 	 * Execute permission is checked against pathname passed to do_execve()
 	 * using current domain.
 	 */
-	if (!domain) {
-		struct tomoyo_domain_info *next_domain = NULL;
-		int retval = tomoyo_find_next_domain(bprm, &next_domain);
-
-		if (!retval)
-			bprm->cred->security = next_domain;
-		return retval;
-	}
+	if (!domain)
+		return tomoyo_find_next_domain(bprm);
 	/*
 	 * Read permission is checked against interpreters using next domain.
 	 * '1' is the result of open_to_namei_flags(O_RDONLY).

security/tomoyo/tomoyo.h

@@ -31,8 +31,7 @@ int tomoyo_check_2path_perm(struct tomoyo_domain_info *domain,
 			    struct path *path2);
 int tomoyo_check_rewrite_permission(struct tomoyo_domain_info *domain,
 				    struct file *filp);
-int tomoyo_find_next_domain(struct linux_binprm *bprm,
-			    struct tomoyo_domain_info **next_domain);
+int tomoyo_find_next_domain(struct linux_binprm *bprm);
 
 /* Index numbers for Access Controls. */