diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
index d64967c..58e6cbce4 100644
--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -161,7 +161,13 @@
 				ret = r;
 				continue;
 			}
-			v9ses->dfltuid = option;
+			v9ses->dfltuid = make_kuid(current_user_ns(), option);
+			if (!uid_valid(v9ses->dfltuid)) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "uid field, but not a uid?\n");
+				ret = -EINVAL;
+				continue;
+			}
 			break;
 		case Opt_dfltgid:
 			r = match_int(&args[0], &option);
@@ -171,7 +177,13 @@
 				ret = r;
 				continue;
 			}
-			v9ses->dfltgid = option;
+			v9ses->dfltgid = make_kgid(current_user_ns(), option);
+			if (!gid_valid(v9ses->dfltgid)) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "gid field, but not a gid?\n");
+				ret = -EINVAL;
+				continue;
+			}
 			break;
 		case Opt_afid:
 			r = match_int(&args[0], &option);
@@ -248,8 +260,9 @@
 			else if (strcmp(s, "client") == 0) {
 				v9ses->flags |= V9FS_ACCESS_CLIENT;
 			} else {
+				uid_t uid;
 				v9ses->flags |= V9FS_ACCESS_SINGLE;
-				v9ses->uid = simple_strtoul(s, &e, 10);
+				uid = simple_strtoul(s, &e, 10);
 				if (*e != '\0') {
 					ret = -EINVAL;
 					pr_info("Unknown access argument %s\n",
@@ -257,6 +270,13 @@
 					kfree(s);
 					goto free_and_return;
 				}
+				v9ses->uid = make_kuid(current_user_ns(), uid);
+				if (!uid_valid(v9ses->uid)) {
+					ret = -EINVAL;
+					pr_info("Uknown uid %s\n", s);
+					kfree(s);
+					goto free_and_return;
+				}
 			}
 
 			kfree(s);
@@ -319,7 +339,7 @@
 	list_add(&v9ses->slist, &v9fs_sessionlist);
 	spin_unlock(&v9fs_sessionlist_lock);
 
-	v9ses->uid = ~0;
+	v9ses->uid = INVALID_UID;
 	v9ses->dfltuid = V9FS_DEFUID;
 	v9ses->dfltgid = V9FS_DEFGID;
 
@@ -364,7 +384,7 @@
 
 		v9ses->flags &= ~V9FS_ACCESS_MASK;
 		v9ses->flags |= V9FS_ACCESS_ANY;
-		v9ses->uid = ~0;
+		v9ses->uid = INVALID_UID;
 	}
 	if (!v9fs_proto_dotl(v9ses) ||
 		!((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
index 34c59f1..a8e127c 100644
--- a/fs/9p/v9fs.h
+++ b/fs/9p/v9fs.h
@@ -109,9 +109,9 @@
 	char *uname;		/* user name to mount as */
 	char *aname;		/* name of remote hierarchy being mounted */
 	unsigned int maxdata;	/* max data for client interface */
-	unsigned int dfltuid;	/* default uid/muid for legacy support */
-	unsigned int dfltgid;	/* default gid for legacy support */
-	u32 uid;		/* if ACCESS_SINGLE, the uid that has access */
+	kuid_t dfltuid;		/* default uid/muid for legacy support */
+	kgid_t dfltgid;		/* default gid for legacy support */
+	kuid_t uid;		/* if ACCESS_SINGLE, the uid that has access */
 	struct p9_client *clnt;	/* 9p client */
 	struct list_head slist; /* list of sessions registered with v9fs */
 	struct backing_dev_info bdi;
@@ -165,8 +165,8 @@
 #define V9FS_PORT	564
 #define V9FS_DEFUSER	"nobody"
 #define V9FS_DEFANAME	""
-#define V9FS_DEFUID	(-2)
-#define V9FS_DEFGID	(-2)
+#define V9FS_DEFUID	KUIDT_INIT(-2)
+#define V9FS_DEFGID	KGIDT_INIT(-2)
 
 static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
 {