audit: use macros for unset inode and device values

Clean up a number of places were casted magic numbers are used to represent
unset inode and device numbers in preparation for the audit by executable path
patch set.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: enclosed the _UNSET macros in parentheses for ./scripts/checkpatch]
Signed-off-by: Paul Moore <pmoore@redhat.com>

include/linux/audit.h

@@ -27,6 +27,9 @@
 #include <linux/ptrace.h>
 #include <uapi/linux/audit.h>
 
+#define AUDIT_INO_UNSET ((unsigned long)-1)
+#define AUDIT_DEV_UNSET ((dev_t)-1)
+
 struct audit_sig_info {
 	uid_t		uid;
 	pid_t		pid;

kernel/audit.c

@@ -1759,7 +1759,7 @@ void audit_log_name(struct audit_context *context, struct audit_names *n,
 	} else
 		audit_log_format(ab, " name=(null)");
 
-	if (n->ino != (unsigned long)-1) {
+	if (n->ino != AUDIT_INO_UNSET) {
 		audit_log_format(ab, " inode=%lu"
 				 " dev=%02x:%02x mode=%#ho"
 				 " ouid=%u ogid=%u rdev=%02x:%02x",

kernel/audit_watch.c

@@ -138,7 +138,7 @@ char *audit_watch_path(struct audit_watch *watch)
 
 int audit_watch_compare(struct audit_watch *watch, unsigned long ino, dev_t dev)
 {
-	return (watch->ino != (unsigned long)-1) &&
+	return (watch->ino != AUDIT_INO_UNSET) &&
 		(watch->ino == ino) &&
 		(watch->dev == dev);
 }
@@ -179,8 +179,8 @@ static struct audit_watch *audit_init_watch(char *path)
 	INIT_LIST_HEAD(&watch->rules);
 	atomic_set(&watch->count, 1);
 	watch->path = path;
-	watch->dev = (dev_t)-1;
-	watch->ino = (unsigned long)-1;
+	watch->dev = AUDIT_DEV_UNSET;
+	watch->ino = AUDIT_INO_UNSET;
 
 	return watch;
 }
@@ -493,7 +493,7 @@ static int audit_watch_handle_event(struct fsnotify_group *group,
 	if (mask & (FS_CREATE|FS_MOVED_TO) && inode)
 		audit_update_watch(parent, dname, inode->i_sb->s_dev, inode->i_ino, 0);
 	else if (mask & (FS_DELETE|FS_MOVED_FROM))
-		audit_update_watch(parent, dname, (dev_t)-1, (unsigned long)-1, 1);
+		audit_update_watch(parent, dname, AUDIT_DEV_UNSET, AUDIT_INO_UNSET, 1);
 	else if (mask & (FS_DELETE_SELF|FS_UNMOUNT|FS_MOVE_SELF))
 		audit_remove_parent_watches(parent);
 

kernel/auditsc.c

@@ -180,7 +180,7 @@ static int audit_match_filetype(struct audit_context *ctx, int val)
 		return 0;
 
 	list_for_each_entry(n, &ctx->names_list, list) {
-		if ((n->ino != -1) &&
+		if ((n->ino != AUDIT_INO_UNSET) &&
 		    ((n->mode & S_IFMT) == mode))
 			return 1;
 	}
@@ -1681,7 +1681,7 @@ static struct audit_names *audit_alloc_name(struct audit_context *context,
 		aname->should_free = true;
 	}
 
-	aname->ino = (unsigned long)-1;
+	aname->ino = AUDIT_INO_UNSET;
 	aname->type = type;
 	list_add_tail(&aname->list, &context->names_list);
 
@@ -1923,7 +1923,7 @@ void __audit_inode_child(const struct inode *parent,
 	if (inode)
 		audit_copy_inode(found_child, dentry, inode);
 	else
-		found_child->ino = (unsigned long)-1;
+		found_child->ino = AUDIT_INO_UNSET;
 }
 EXPORT_SYMBOL_GPL(__audit_inode_child);