Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit

Pull audit updates from Paul Moore:
 "Six audit patches for 4.8.

  There are a couple of style and minor whitespace tweaks for the logs,
  as well as a minor fixup to catch errors on user filter rules, however
  the major improvements are a fix to the s390 syscall argument masking
  code (reviewed by the nice s390 folks), some consolidation around the
  exclude filtering (less code, always a win), and a double-fetch fix
  for recording the execve arguments"

* 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit:
  audit: fix a double fetch in audit_log_single_execve_arg()
  audit: fix whitespace in CWD record
  audit: add fields to exclude filter by reusing user filter
  s390: ensure that syscall arguments are properly masked on s390
  audit: fix some horrible switch statement style crimes
  audit: fixup: log on errors from filter user rules

arch/s390/kernel/ptrace.c

@@ -821,6 +821,8 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 
 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 {
+	unsigned long mask = -1UL;
+
 	/*
 	 * The sysc_tracesys code in entry.S stored the system
 	 * call number to gprs[2].
@@ -846,9 +848,12 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 		trace_sys_enter(regs, regs->gprs[2]);
 
-	audit_syscall_entry(regs->gprs[2], regs->orig_gpr2,
-			    regs->gprs[3], regs->gprs[4],
-			    regs->gprs[5]);
+	if (is_compat_task())
+		mask = 0xffffffff;
+
+	audit_syscall_entry(regs->gprs[2], regs->orig_gpr2 & mask,
+			    regs->gprs[3] &mask, regs->gprs[4] &mask,
+			    regs->gprs[5] &mask);
 
 	return regs->gprs[2];
 }

include/linux/audit.h

@@ -163,8 +163,6 @@ extern void audit_log_task_info(struct audit_buffer *ab,
 extern int		    audit_update_lsm_rules(void);
 
 				/* Private API (for audit.c only) */
-extern int audit_filter_user(int type);
-extern int audit_filter_type(int type);
 extern int audit_rule_change(int type, __u32 portid, int seq,
 				void *data, size_t datasz);
 extern int audit_list_rules_send(struct sk_buff *request_skb, int seq);

kernel/audit.c

@@ -932,7 +932,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		if (!audit_enabled && msg_type != AUDIT_USER_AVC)
 			return 0;
 
-		err = audit_filter_user(msg_type);
+		err = audit_filter(msg_type, AUDIT_FILTER_USER);
 		if (err == 1) { /* match or error */
 			err = 0;
 			if (msg_type == AUDIT_USER_TTY) {
@@ -1379,7 +1379,7 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
 	if (audit_initialized != AUDIT_INITIALIZED)
 		return NULL;
 
-	if (unlikely(audit_filter_type(type)))
+	if (unlikely(!audit_filter(type, AUDIT_FILTER_TYPE)))
 		return NULL;
 
 	if (gfp_mask & __GFP_DIRECT_RECLAIM) {

kernel/audit.h

@@ -331,6 +331,8 @@ extern pid_t audit_sig_pid;
 extern kuid_t audit_sig_uid;
 extern u32 audit_sig_sid;
 
+extern int audit_filter(int msgtype, unsigned int listtype);
+
 #ifdef CONFIG_AUDITSYSCALL
 extern int __audit_signal_info(int sig, struct task_struct *t);
 static inline int audit_signal_info(int sig, struct task_struct *t)

kernel/auditfilter.c

@@ -1290,15 +1290,20 @@ int audit_compare_dname_path(const char *dname, const char *path, int parentlen)
 	return strncmp(p, dname, dlen);
 }
 
-static int audit_filter_user_rules(struct audit_krule *rule, int type,
-				   enum audit_state *state)
+int audit_filter(int msgtype, unsigned int listtype)
 {
-	int i;
+	struct audit_entry *e;
+	int ret = 1; /* Audit by default */
+
+	rcu_read_lock();
+	if (list_empty(&audit_filter_list[listtype]))
+		goto unlock_and_return;
+	list_for_each_entry_rcu(e, &audit_filter_list[listtype], list) {
+		int i, result = 0;
 
-	for (i = 0; i < rule->field_count; i++) {
-		struct audit_field *f = &rule->fields[i];
+		for (i = 0; i < e->rule.field_count; i++) {
+			struct audit_field *f = &e->rule.fields[i];
 			pid_t pid;
-		int result = 0;
 			u32 sid;
 
 			switch (f->type) {
@@ -1321,7 +1326,7 @@ static int audit_filter_user_rules(struct audit_krule *rule, int type,
 							  f->op, f->val);
 				break;
 			case AUDIT_MSGTYPE:
-			result = audit_comparator(type, f->op, f->val);
+				result = audit_comparator(msgtype, f->op, f->val);
 				break;
 			case AUDIT_SUBJ_USER:
 			case AUDIT_SUBJ_ROLE:
@@ -1331,72 +1336,26 @@ static int audit_filter_user_rules(struct audit_krule *rule, int type,
 				if (f->lsm_rule) {
 					security_task_getsecid(current, &sid);
 					result = security_audit_rule_match(sid,
-								   f->type,
-								   f->op,
-								   f->lsm_rule,
-								   NULL);
+							f->type, f->op, f->lsm_rule, NULL);
 				}
 				break;
+			default:
+				goto unlock_and_return;
 			}
-
-		if (!result)
-			return 0;
-	}
-	switch (rule->action) {
-	case AUDIT_NEVER:    *state = AUDIT_DISABLED;	    break;
-	case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
-	}
-	return 1;
-}
-
-int audit_filter_user(int type)
-{
-	enum audit_state state = AUDIT_DISABLED;
-	struct audit_entry *e;
-	int rc, ret;
-
-	ret = 1; /* Audit by default */
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) {
-		rc = audit_filter_user_rules(&e->rule, type, &state);
-		if (rc) {
-			if (rc > 0 && state == AUDIT_DISABLED)
-				ret = 0;
-			break;
-		}
-	}
-	rcu_read_unlock();
-
-	return ret;
-}
-
-int audit_filter_type(int type)
-{
-	struct audit_entry *e;
-	int result = 0;
-
-	rcu_read_lock();
-	if (list_empty(&audit_filter_list[AUDIT_FILTER_TYPE]))
+			if (result < 0) /* error */
 				goto unlock_and_return;
-
-	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TYPE],
-				list) {
-		int i;
-		for (i = 0; i < e->rule.field_count; i++) {
-			struct audit_field *f = &e->rule.fields[i];
-			if (f->type == AUDIT_MSGTYPE) {
-				result = audit_comparator(type, f->op, f->val);
 			if (!result)
 				break;
 		}
+		if (result > 0) {
+			if (e->rule.action == AUDIT_NEVER || listtype == AUDIT_FILTER_TYPE)
+				ret = 0;
+			break;
 		}
-		if (result)
-			goto unlock_and_return;
 	}
 unlock_and_return:
 	rcu_read_unlock();
-	return result;
+	return ret;
 }
 
 static int update_lsm_rule(struct audit_krule *r)