diff --git a/bin/mkdir/minix-port.patch b/bin/mkdir/minix-port.patch
deleted file mode 100644
index e69de29bb..000000000
diff --git a/common/include/minix/callnr.h b/common/include/minix/callnr.h
index 0236fcf04..5af4baaa8 100644
--- a/common/include/minix/callnr.h
+++ b/common/include/minix/callnr.h
@@ -30,7 +30,10 @@
 #define PREV_FSTAT	  28
 #define PAUSE		  29
 #define UTIME		  30 
+#define GETEPINFO	  31
+#define SETGROUPS	  32
 #define ACCESS		  33 
+#define GETGROUPS	  34
 #define SYNC		  36 
 #define KILL		  37
 #define RENAME		  38
@@ -54,8 +57,8 @@
 #define SETSID		  62
 #define GETPGRP		  63
 #define ITIMER		  64
-#define GETGROUPS	  65
-#define SETGROUPS	  66
+#define GETGROUPS_O	  65
+#define SETGROUPS_O	  66
 #define GETMCONTEXT       67
 #define SETMCONTEXT       68
 
@@ -100,7 +103,7 @@
 #define PROCSTAT	103	/* to PM */
 #define GETPROCNR	104	/* to PM */
 
-#define GETEPINFO	107	/* to PM: get pid/uid/gid of an endpoint */
+#define GETEPINFO_O	107	/* to PM: get pid/uid/gid of an endpoint */
 #define ADDDMA		108	/* to PM: inform PM about a region of memory
 				 * that is used for bus-master DMA
 				 */
diff --git a/include/limits.h b/include/limits.h
index 3a69ea2e1..792d3c1d8 100644
--- a/include/limits.h
+++ b/include/limits.h
@@ -113,4 +113,7 @@
 #define IOV_MAX        INT_MAX  /* maximum number of buffers for readv/writev */
 #endif /* _POSIX_SOURCE */
 
+#define GID_MAX		USHRT_MAX
+#define UID_MAX		USHRT_MAX
+
 #endif /* _LIMITS_H */
diff --git a/include/minix/types.h b/include/minix/types.h
index 4c46763dd..1c7ba40be 100644
--- a/include/minix/types.h
+++ b/include/minix/types.h
@@ -104,7 +104,7 @@ typedef u32_t          big_dev_t;
 /* Types used in disk, inode, etc. data structures.
  * Some u64_t should be i64_t, but anyway with old libc we use .lo only.
  */
-typedef char           gid_t;	   /* group id */
+typedef u32_t          gid_t;	   /* group id */
 typedef u32_t          big_gid_t;  /* group id */
 typedef unsigned long  ino_t; 	   /* i-node number (V3 filesystem) */
 typedef u64_t          big_ino_t;  /* i-node number (V3 filesystem) */
@@ -115,7 +115,7 @@ typedef u32_t          big_nlink_t;/* number of links to a file */
 typedef long	       off_t;	   /* offset within a file */
 typedef u64_t          big_off_t;  /* offset within a file */
 typedef int            pid_t;	   /* process id (must be signed) */
-typedef short          uid_t;	   /* user id */
+typedef u32_t          uid_t;	   /* user id */
 typedef u32_t          big_uid_t;  /* user id */
 typedef unsigned long  fsblkcnt_t; /* File system block count */
 typedef unsigned long  fsfilcnt_t; /* File system file count */
diff --git a/include/net/ioctl.h b/include/net/ioctl.h
index 71ca4752b..9efb13a66 100644
--- a/include/net/ioctl.h
+++ b/include/net/ioctl.h
@@ -84,6 +84,7 @@ struct msg_control
 
 /* setsockopt/setsockopt for unix domain sockets */
 #define NWIOGUDSSOTYPE	 _IOR('n', 90, int)		  /* SO_TYPE */
+#define NWIOGUDSPEERCREDOLD _IOR('n', 91, struct ucred_old)  /* SO_PEERCRED */
 #define NWIOGUDSPEERCRED _IOR('n', 91, struct ucred)	  /* SO_PEERCRED */
 #define NWIOGUDSSNDBUF	 _IOR('n', 92, size_t)            /* SO_SNDBUF */
 #define NWIOSUDSSNDBUF	 _IOW('n', 93, size_t)            /* SO_SNDBUF */
diff --git a/include/sys/stat.h b/include/sys/stat.h
index ee7b7fc8a..71e4a43ac 100644
--- a/include/sys/stat.h
+++ b/include/sys/stat.h
@@ -51,7 +51,7 @@ struct minix_prev_stat {
   ino_t st_ino;			/* i-node number */
   mode_t st_mode;		/* file mode, protection bits, etc. */
   nlink_t st_nlink;		/* # links; */
-  uid_t st_uid;			/* uid of the file's owner */
+  short st_uid;			/* uid of the file's owner */
   short int st_gid;		/* gid; TEMPORARY HACK: should be gid_t */
   short st_rdev;
   off_t st_size;		/* file size */
diff --git a/include/sys/ucred.h b/include/sys/ucred.h
index c88422d02..5babf6fb5 100644
--- a/include/sys/ucred.h
+++ b/include/sys/ucred.h
@@ -1,11 +1,18 @@
 #ifndef __SYS_UCRED_H
 #define __SYS_UCRED_H
 
-struct ucred
+struct ucred_old
 {
 	pid_t   pid;
-	uid_t   uid;
-	gid_t   gid;
+	short   uid;
+	char    gid;
+};
+
+struct ucred
+{
+	pid_t	pid;
+	uid_t	uid;
+	gid_t	gid;
 };
 
 #endif
diff --git a/lib/libc/other/fslib.c b/lib/libc/other/fslib.c
index bcbcd24c5..0ef6ad30b 100644
--- a/lib/libc/other/fslib.c
+++ b/lib/libc/other/fslib.c
@@ -164,9 +164,9 @@ int norm;			/* TRUE = do not swap bytes; FALSE = swap */
   if (direction == READING) {
 	/* Copy V2.x inode to the in-core table, swapping bytes if need be. */
 	rip->i_mode    = conv2(norm,dip->d2_mode);
-	rip->i_uid     = conv2(norm,dip->d2_uid );
+	rip->i_uid     = conv4(norm,dip->d2_uid );
 	rip->i_nlinks  = conv2(norm,(int) dip->d2_nlinks);
-	rip->i_gid     = conv2(norm,(int) dip->d2_gid );
+	rip->i_gid     = conv4(norm,(int) dip->d2_gid );
 	rip->i_size    = conv4(norm,dip->d2_size);
 	rip->i_atime   = conv4(norm,dip->d2_atime);
 	rip->i_ctime   = conv4(norm,dip->d2_ctime);
@@ -178,9 +178,9 @@ int norm;			/* TRUE = do not swap bytes; FALSE = swap */
   } else {
 	/* Copying V2.x inode to disk from the in-core table. */
 	dip->d2_mode   = conv2(norm,rip->i_mode);
-	dip->d2_uid    = conv2(norm,rip->i_uid );
+	dip->d2_uid    = conv4(norm,rip->i_uid );
 	dip->d2_nlinks = conv2(norm,rip->i_nlinks);
-	dip->d2_gid    = conv2(norm,rip->i_gid );
+	dip->d2_gid    = conv4(norm,rip->i_gid );
 	dip->d2_size   = conv4(norm,rip->i_size);
 	dip->d2_atime  = conv4(norm,rip->i_atime);
 	dip->d2_ctime  = conv4(norm,rip->i_ctime);
diff --git a/lib/libc/posix/_getgroups.c b/lib/libc/posix/_getgroups.c
index 27d2d6a53..39a7c6362 100644
--- a/lib/libc/posix/_getgroups.c
+++ b/lib/libc/posix/_getgroups.c
@@ -10,7 +10,7 @@ PUBLIC int getgroups(int ngroups, gid_t *arr)
 {
   message m;
   m.m1_i1 = ngroups;
-  m.m1_p1 = arr;
+  m.m1_p1 = (char *) arr;
 
   return(_syscall(PM_PROC_NR, GETGROUPS, &m));
 }
diff --git a/lib/nbsd_libc/gen/getgrent.c b/lib/nbsd_libc/gen/getgrent.c
index de0c9ea51..9e2b6957f 100644
--- a/lib/nbsd_libc/gen/getgrent.c
+++ b/lib/nbsd_libc/gen/getgrent.c
@@ -481,11 +481,7 @@ static int
 _files_getgrgid(void *nsrv, void *nscb, va_list ap)
 {
 	struct group	**retval = va_arg(ap, struct group **);
-#ifdef __minix
-	gid_t		 gid	= (gid_t)va_arg(ap, int);
-#else
 	gid_t		 gid	= va_arg(ap, gid_t);
-#endif
 
 	int	rv, rerror;
 
@@ -510,11 +506,7 @@ static int
 _files_getgrgid_r(void *nsrv, void *nscb, va_list ap)
 {
 	int		*retval	= va_arg(ap, int *);
-#ifdef __minix
-	gid_t		 gid	= (gid_t)va_arg(ap, int);
-#else
 	gid_t		 gid	= va_arg(ap, gid_t);
-#endif
 	struct group	*grp	= va_arg(ap, struct group *);
 	char		*buffer	= va_arg(ap, char *);
 	size_t		 buflen	= va_arg(ap, size_t);
@@ -809,11 +801,7 @@ static int
 _dns_getgrgid(void *nsrv, void *nscb, va_list ap)
 {
 	struct group	**retval = va_arg(ap, struct group **);
-#ifdef __minix
-	gid_t		 gid	= (gid_t)va_arg(ap, int);
-#else
 	gid_t		 gid	= va_arg(ap, gid_t);
-#endif
 
 	int	rv, rerror;
 
@@ -837,11 +825,7 @@ static int
 _dns_getgrgid_r(void *nsrv, void *nscb, va_list ap)
 {
 	int		*retval	= va_arg(ap, int *);
-#ifdef __minix
-	gid_t		 gid	= (gid_t)va_arg(ap, int);
-#else
 	gid_t		 gid	= va_arg(ap, gid_t);
-#endif
 	struct group	*grp	= va_arg(ap, struct group *);
 	char		*buffer	= va_arg(ap, char *);
 	size_t		 buflen	= va_arg(ap, size_t);
@@ -1164,11 +1148,7 @@ static int
 _nis_getgrgid(void *nsrv, void *nscb, va_list ap)
 {
 	struct group	**retval = va_arg(ap, struct group **);
-#ifdef __minix
-	gid_t		 gid	= (gid_t)va_arg(ap, int);
-#else
 	gid_t		 gid	= va_arg(ap, gid_t);
-#endif
 
 	int	rv, rerror;
 
@@ -1192,11 +1172,7 @@ static int
 _nis_getgrgid_r(void *nsrv, void *nscb, va_list ap)
 {
 	int		*retval	= va_arg(ap, int *);
-#ifdef __minix
-	gid_t		 gid	= (gid_t)va_arg(ap, int);
-#else
 	gid_t		 gid	= va_arg(ap, gid_t);
-#endif
 	struct group	*grp	= va_arg(ap, struct group *);
 	char		*buffer	= va_arg(ap, char *);
 	size_t		 buflen	= va_arg(ap, size_t);
@@ -1432,11 +1408,7 @@ __grscan_compat(int *retval, struct group *grp, char *buffer, size_t buflen,
 				crv = nsdispatch(NULL, compatgiddtab,
 				    NSDB_GROUP_COMPAT, "getgrgid_r",
 				    __nsdefaultnis,
-#ifdef __minix
-				    &cretval, (int)gid,
-#else
 				    &cretval, gid,
-#endif
 				    &cgrp, filebuf, sizeof(filebuf), &cgrpres);
 			}
 			if (crv != NS_SUCCESS) {	/* not found */
@@ -1638,11 +1610,7 @@ static int
 _compat_getgrgid(void *nsrv, void *nscb, va_list ap)
 {
 	struct group	**retval = va_arg(ap, struct group **);
-#ifdef __minix
-	gid_t		 gid	= (gid_t)va_arg(ap, int);
-#else
 	gid_t		 gid	= va_arg(ap, gid_t);
-#endif
 
 	int	rv, rerror;
 
@@ -1667,11 +1635,7 @@ static int
 _compat_getgrgid_r(void *nsrv, void *nscb, va_list ap)
 {
 	int		*retval	= va_arg(ap, int *);
-#ifdef __minix
-	gid_t		 gid	= (gid_t)va_arg(ap, int);
-#else
 	gid_t		 gid	= va_arg(ap, gid_t);
-#endif
 	struct group	*grp	= va_arg(ap, struct group *);
 	char		*buffer	= va_arg(ap, char *);
 	size_t		 buflen	= va_arg(ap, size_t);
@@ -1821,11 +1785,7 @@ getgrgid(gid_t gid)
 
 	mutex_lock(&__grmutex);
 	rv = nsdispatch(NULL, dtab, NSDB_GROUP, "getgrgid", __nsdefaultcompat,
-#ifdef __minix
-	    &retval, (int)gid);
-#else
 	    &retval, gid);
-#endif
 	mutex_unlock(&__grmutex);
 	return (rv == NS_SUCCESS) ? retval : NULL;
 }
@@ -1852,11 +1812,7 @@ getgrgid_r(gid_t gid, struct group *grp, char *buffer, size_t buflen,
 	retval = 0;
 	mutex_lock(&__grmutex);
 	rv = nsdispatch(NULL, dtab, NSDB_GROUP, "getgrgid_r", __nsdefaultcompat,
-#ifdef __minix
-	    &retval, (int)gid, grp, buffer, buflen, result);
-#else
 	    &retval, gid, grp, buffer, buflen, result);
-#endif
 	mutex_unlock(&__grmutex);
 	switch (rv) {
 	case NS_SUCCESS:
diff --git a/lib/nbsd_libc/gen/getgroupmembership.c b/lib/nbsd_libc/gen/getgroupmembership.c
index 2c8a40540..78687c0a5 100644
--- a/lib/nbsd_libc/gen/getgroupmembership.c
+++ b/lib/nbsd_libc/gen/getgroupmembership.c
@@ -101,11 +101,7 @@ _files_getgroupmembership(void *retval, void *cb_data, va_list ap)
 {
 	int		*result	= va_arg(ap, int *);
 	const char 	*uname	= va_arg(ap, const char *);
-#ifdef __minix
-	gid_t		 agroup = (gid_t)va_arg(ap, int);
-#else
 	gid_t		 agroup	= va_arg(ap, gid_t);
-#endif
 	gid_t		*groups	= va_arg(ap, gid_t *);
 	int		 maxgrp	= va_arg(ap, int);
 	int		*groupc	= va_arg(ap, int *);
@@ -148,11 +144,7 @@ _dns_getgroupmembership(void *retval, void *cb_data, va_list ap)
 {
 	int		*result	= va_arg(ap, int *);
 	const char 	*uname	= va_arg(ap, const char *);
-#ifdef __minix
-	gid_t		 agroup = (gid_t)va_arg(ap, int);
-#else
 	gid_t		 agroup	= va_arg(ap, gid_t);
-#endif
 	gid_t		*groups	= va_arg(ap, gid_t *);
 	int		 maxgrp	= va_arg(ap, int);
 	int		*groupc	= va_arg(ap, int *);
@@ -245,11 +237,7 @@ _nis_getgroupmembership(void *retval, void *cb_data, va_list ap)
 {
 	int		*result	= va_arg(ap, int *);
 	const char 	*uname	= va_arg(ap, const char *);
-#ifdef __minix
-	gid_t		 agroup = (gid_t)va_arg(ap, int);
-#else
 	gid_t		 agroup	= va_arg(ap, gid_t);
-#endif
 	gid_t		*groups	= va_arg(ap, gid_t *);
 	int		 maxgrp	= va_arg(ap, int);
 	int		*groupc	= va_arg(ap, int *);
@@ -317,11 +305,7 @@ _compat_ggm_search(void *cookie, struct group **groupres)
 	crv = nsdispatch(NULL, dtab,
 	    NSDB_GROUP_COMPAT, "getgroupmembership",
 	    __nsdefaultnis,
-#ifdef __minix
-	    &rerror, cp->uname, (int)cp->agroup, cp->groups, cp->maxgrp, cp->groupc);
-#else
 	    &rerror, cp->uname, cp->agroup, cp->groups, cp->maxgrp, cp->groupc);
-#endif
 
 	if (crv == NS_SUCCESS)
 		crv = NS_NOTFOUND;	/* indicate "no more +: entries" */
@@ -335,11 +319,7 @@ _compat_getgroupmembership(void *retval, void *cb_data, va_list ap)
 {
 	int		*result	= va_arg(ap, int *);
 	const char 	*uname	= va_arg(ap, const char *);
-#ifdef __minix
-	gid_t		 agroup = (gid_t)va_arg(ap, int);
-#else
 	gid_t		 agroup	= va_arg(ap, gid_t);
-#endif
 	gid_t		*groups	= va_arg(ap, gid_t *);
 	int		 maxgrp	= va_arg(ap, int);
 	int		*groupc	= va_arg(ap, int *);
@@ -415,11 +395,7 @@ getgroupmembership(const char *uname, gid_t agroup,
 			 */
 	(void) nsdispatch(NULL, dtab, NSDB_GROUP, "getgroupmembership",
 	    __nsdefaultcompat,
-#ifdef __minix
-	    &rerror, uname, (int)agroup, groups, maxgrp, groupc);
-#else
 	    &rerror, uname, agroup, groups, maxgrp, groupc);
-#endif
 	mutex_unlock(&__grmutex);
 
 	if (*groupc > maxgrp)			/* too many groups found */
diff --git a/lib/nbsd_libc/gen/getpwent.c b/lib/nbsd_libc/gen/getpwent.c
index 1250fc73a..44abb45fd 100644
--- a/lib/nbsd_libc/gen/getpwent.c
+++ b/lib/nbsd_libc/gen/getpwent.c
@@ -671,11 +671,7 @@ static int
 _files_getpwuid(void *nsrv, void *nscb, va_list ap)
 {
 	struct passwd	**retval = va_arg(ap, struct passwd **);
-#ifdef __minix
-	uid_t		 uid	= (uid_t)va_arg(ap, int);
-#else
 	uid_t		 uid	= va_arg(ap, uid_t);
-#endif
 
 	int	rv, rerror;
 
@@ -700,11 +696,7 @@ static int
 _files_getpwuid_r(void *nsrv, void *nscb, va_list ap)
 {
 	int		*retval	= va_arg(ap, int *);
-#ifdef __minix
-	uid_t		 uid	= (uid_t)va_arg(ap, int);
-#else
 	uid_t		 uid	= va_arg(ap, uid_t);
-#endif
 	struct passwd	*pw	= va_arg(ap, struct passwd *);
 	char		*buffer	= va_arg(ap, char *);
 	size_t		 buflen	= va_arg(ap, size_t);
@@ -1000,11 +992,7 @@ static int
 _dns_getpwuid(void *nsrv, void *nscb, va_list ap)
 {
 	struct passwd	**retval = va_arg(ap, struct passwd **);
-#ifdef __minix
-	uid_t		 uid	= (uid_t)va_arg(ap, int);
-#else
 	uid_t		 uid	= va_arg(ap, uid_t);
-#endif
 
 	int	rv, rerror;
 
@@ -1031,11 +1019,7 @@ static int
 _dns_getpwuid_r(void *nsrv, void *nscb, va_list ap)
 {
 	int		*retval	= va_arg(ap, int *);
-#ifdef __minix
-	uid_t		 uid	= (uid_t)va_arg(ap, int);
-#else
 	uid_t		 uid	= va_arg(ap, uid_t);
-#endif
 	struct passwd	*pw	= va_arg(ap, struct passwd *);
 	char		*buffer	= va_arg(ap, char *);
 	size_t		 buflen	= va_arg(ap, size_t);
@@ -1524,11 +1508,7 @@ static int
 _nis_getpwuid(void *nsrv, void *nscb, va_list ap)
 {
 	struct passwd	**retval = va_arg(ap, struct passwd **);
-#ifdef __minix
-	uid_t		 uid	= (uid_t)va_arg(ap, int);
-#else
 	uid_t		 uid	= va_arg(ap, uid_t);
-#endif
 
 	int	rv, rerror;
 
@@ -1554,11 +1534,7 @@ static int
 _nis_getpwuid_r(void *nsrv, void *nscb, va_list ap)
 {
 	int		*retval	= va_arg(ap, int *);
-#ifdef __minix
-	uid_t		 uid	= (uid_t)va_arg(ap, int);
-#else
 	uid_t		 uid	= va_arg(ap, uid_t);
-#endif
 	struct passwd	*pw	= va_arg(ap, struct passwd *);
 	char		*buffer	= va_arg(ap, char *);
 	size_t		 buflen	= va_arg(ap, size_t);
@@ -1920,15 +1896,9 @@ _passwdcompat_pwscan(struct passwd *pw, char *buffer, size_t buflen,
 		    &crv, name, pw, buffer, buflen, &cpw);
 		break;
 	case _PW_KEYBYUID:
-#ifdef __minix
-		rv = nsdispatch(NULL, compatuiddtab,
-		    NSDB_PASSWD_COMPAT, "getpwuid_r", __nsdefaultnis,
-		    &crv, (int)uid, pw, buffer, buflen, &cpw);
-#else
 		rv = nsdispatch(NULL, compatuiddtab,
 		    NSDB_PASSWD_COMPAT, "getpwuid_r", __nsdefaultnis,
 		    &crv, uid, pw, buffer, buflen, &cpw);
-#endif
 		break;
 	default:
 		abort();
@@ -2331,11 +2301,7 @@ static int
 _compat_getpwuid(void *nsrv, void *nscb, va_list ap)
 {
 	struct passwd	**retval = va_arg(ap, struct passwd **);
-#ifdef __minix
-	uid_t		 uid	= (uid_t)va_arg(ap, int);
-#else
 	uid_t		 uid	= va_arg(ap, uid_t);
-#endif
 
 	int	rv, rerror;
 
@@ -2360,11 +2326,7 @@ static int
 _compat_getpwuid_r(void *nsrv, void *nscb, va_list ap)
 {
 	int		*retval	= va_arg(ap, int *);
-#ifdef __minix
-	uid_t		 uid	= (uid_t)va_arg(ap, int);
-#else
 	uid_t		 uid	= va_arg(ap, uid_t);
-#endif
 	struct passwd	*pw	= va_arg(ap, struct passwd *);
 	char		*buffer	= va_arg(ap, char *);
 	size_t		 buflen	= va_arg(ap, size_t);
@@ -2520,13 +2482,8 @@ getpwuid(uid_t uid)
 	};
 
 	mutex_lock(&_pwmutex);
-#ifdef __minix
-	rv = nsdispatch(NULL, dtab, NSDB_PASSWD, "getpwuid", __nsdefaultcompat,
-	    &retval, (int)uid);
-#else
 	rv = nsdispatch(NULL, dtab, NSDB_PASSWD, "getpwuid", __nsdefaultcompat,
 	    &retval, uid);
-#endif
 	mutex_unlock(&_pwmutex);
 	return (rv == NS_SUCCESS) ? retval : NULL;
 }
@@ -2552,13 +2509,8 @@ getpwuid_r(uid_t uid, struct passwd *pwd, char *buffer, size_t buflen,
 	*result = NULL;
 	retval = 0;
 	mutex_lock(&_pwmutex);
-#ifdef __minix
-	r = nsdispatch(NULL, dtab, NSDB_PASSWD, "getpwuid_r", __nsdefaultcompat,
-	    &retval, (int)uid, pwd, buffer, buflen, result);
-#else
 	r = nsdispatch(NULL, dtab, NSDB_PASSWD, "getpwuid_r", __nsdefaultcompat,
 	    &retval, uid, pwd, buffer, buflen, result);
-#endif
 
 	mutex_unlock(&_pwmutex);
 	switch (r) {
diff --git a/lib/nbsd_libminlib/fslib.c b/lib/nbsd_libminlib/fslib.c
index bcbcd24c5..0ef6ad30b 100644
--- a/lib/nbsd_libminlib/fslib.c
+++ b/lib/nbsd_libminlib/fslib.c
@@ -164,9 +164,9 @@ int norm;			/* TRUE = do not swap bytes; FALSE = swap */
   if (direction == READING) {
 	/* Copy V2.x inode to the in-core table, swapping bytes if need be. */
 	rip->i_mode    = conv2(norm,dip->d2_mode);
-	rip->i_uid     = conv2(norm,dip->d2_uid );
+	rip->i_uid     = conv4(norm,dip->d2_uid );
 	rip->i_nlinks  = conv2(norm,(int) dip->d2_nlinks);
-	rip->i_gid     = conv2(norm,(int) dip->d2_gid );
+	rip->i_gid     = conv4(norm,(int) dip->d2_gid );
 	rip->i_size    = conv4(norm,dip->d2_size);
 	rip->i_atime   = conv4(norm,dip->d2_atime);
 	rip->i_ctime   = conv4(norm,dip->d2_ctime);
@@ -178,9 +178,9 @@ int norm;			/* TRUE = do not swap bytes; FALSE = swap */
   } else {
 	/* Copying V2.x inode to disk from the in-core table. */
 	dip->d2_mode   = conv2(norm,rip->i_mode);
-	dip->d2_uid    = conv2(norm,rip->i_uid );
+	dip->d2_uid    = conv4(norm,rip->i_uid );
 	dip->d2_nlinks = conv2(norm,rip->i_nlinks);
-	dip->d2_gid    = conv2(norm,rip->i_gid );
+	dip->d2_gid    = conv4(norm,rip->i_gid );
 	dip->d2_size   = conv4(norm,rip->i_size);
 	dip->d2_atime  = conv4(norm,rip->i_atime);
 	dip->d2_ctime  = conv4(norm,rip->i_ctime);
diff --git a/nbsd_include/sys/ansi.h b/nbsd_include/sys/ansi.h
index 2f9365892..c17ca9e2a 100644
--- a/nbsd_include/sys/ansi.h
+++ b/nbsd_include/sys/ansi.h
@@ -35,7 +35,7 @@
 #include <machine/ansi.h>
 
 typedef char *		__caddr_t;	/* core address */
-typedef char	   	__gid_t;	/* group id */
+typedef __uint32_t   	__gid_t;	/* group id */
 typedef __uint32_t	__in_addr_t;	/* IP(v4) address */
 typedef __uint16_t	__in_port_t;	/* "Internet" port number */
 typedef unsigned short	__mode_t;	/* file permissions */
@@ -43,7 +43,7 @@ typedef long 		__off_t;	/* file offset */
 typedef int		__pid_t;	/* process id */
 typedef __uint8_t	__sa_family_t;	/* socket address family */
 typedef __int32_t	__socklen_t;	/* socket-related datum length */
-typedef short	   	__uid_t;	/* user id */
+typedef __uint32_t   	__uid_t;	/* user id */
 typedef	unsigned long	__fsblkcnt_t;	/* fs block count (statvfs) */
 typedef	unsigned long	__fsfilcnt_t;	/* fs file count */
 
diff --git a/nbsd_include/sys/stat.h b/nbsd_include/sys/stat.h
index fd89f9def..79bb8e58b 100644
--- a/nbsd_include/sys/stat.h
+++ b/nbsd_include/sys/stat.h
@@ -46,7 +46,7 @@ struct minix_prev_stat {
   ino_t st_ino;			/* i-node number */
   mode_t st_mode;		/* file mode, protection bits, etc. */
   nlink_t st_nlink;		/* # links; */
-  uid_t st_uid;			/* uid of the file's owner */
+  short st_uid;			/* uid of the file's owner */
   short int st_gid;		/* gid; TEMPORARY HACK: should be gid_t */
   short st_rdev;
   off_t st_size;		/* file size */
diff --git a/nbsd_include/sys/syslimits.h b/nbsd_include/sys/syslimits.h
index 117eadbcf..4fb0039dc 100644
--- a/nbsd_include/sys/syslimits.h
+++ b/nbsd_include/sys/syslimits.h
@@ -22,13 +22,13 @@
 #define	CHILD_MAX	_NO_LIMIT /* max simultaneous processes */
 #endif
 
-#define GID_MAX	      CHAR_MAX  /* max value for a gid_t */
+#define GID_MAX	      USHRT_MAX  /* max value for a gid_t */
 #define LINK_MAX      SHRT_MAX	/* # links a file may have */
 #define MAX_CANON          255	/* size of the canonical input queue */
 #define MAX_INPUT          255	/* size of the type-ahead buffer */
 #define NAME_MAX           255	/* system-wide max # chars in a file name */
 #define NGROUPS_MAX          8	/* max. number of supplemental groups */
-#define UID_MAX       SHRT_MAX  /* max value for a uid_t */
+#define UID_MAX       USHRT_MAX  /* max value for a uid_t */
 #ifndef OPEN_MAX
 #define	OPEN_MAX __MINIX_OPEN_MAX /* max open files per process */
 #endif
diff --git a/nbsd_include/sys/ucred.h b/nbsd_include/sys/ucred.h
index 15cda1ff9..5babf6fb5 100644
--- a/nbsd_include/sys/ucred.h
+++ b/nbsd_include/sys/ucred.h
@@ -1,13 +1,18 @@
 #ifndef __SYS_UCRED_H
 #define __SYS_UCRED_H
 
-#include <sys/types.h>
+struct ucred_old
+{
+	pid_t   pid;
+	short   uid;
+	char    gid;
+};
 
 struct ucred
 {
-	pid_t   pid;
-	uid_t   uid;
-	gid_t   gid;
+	pid_t	pid;
+	uid_t	uid;
+	gid_t	gid;
 };
 
 #endif
diff --git a/servers/apfs/dev_uds.c b/servers/apfs/dev_uds.c
index e16ad099c..05b3adf25 100644
--- a/servers/apfs/dev_uds.c
+++ b/servers/apfs/dev_uds.c
@@ -876,6 +876,13 @@ PUBLIC int uds_ioctl(message *dev_m_in, message *dev_m_out)
 
 			break;
 
+		case NWIOGUDSPEERCREDOLD:
+
+			/* get peer endpoint -- getsockopt(SO_PEERCRED) */
+			rc = do_getsockopt_peercred_old(dev_m_in, dev_m_out);
+
+			break;
+
 		case NWIOSUDSTADDR:
 
 			/* set target address -- sendto() */
diff --git a/servers/apfs/proto.h b/servers/apfs/proto.h
index e0da81367..210e9d1d4 100644
--- a/servers/apfs/proto.h
+++ b/servers/apfs/proto.h
@@ -85,6 +85,8 @@ _PROTOTYPE( int do_getsockopt_sotype,
 				(message *dev_m_in, message *dev_m_out)	);
 _PROTOTYPE( int do_getsockopt_peercred,
 				(message *dev_m_in, message *dev_m_out)	);
+_PROTOTYPE( int do_getsockopt_peercred_old,
+				(message *dev_m_in, message *dev_m_out)	);
 _PROTOTYPE( int do_getsockopt_sndbuf,
 				(message *dev_m_in, message *dev_m_out)	);
 _PROTOTYPE( int do_setsockopt_sndbuf,
diff --git a/servers/apfs/uds.c b/servers/apfs/uds.c
index 67e5ae255..18c70e103 100644
--- a/servers/apfs/uds.c
+++ b/servers/apfs/uds.c
@@ -1045,6 +1045,54 @@ PUBLIC int do_getsockopt_peercred(message *dev_m_in, message *dev_m_out)
 	return rc ? EIO : OK;
 }
 
+PUBLIC int do_getsockopt_peercred_old(message *dev_m_in, message *dev_m_out)
+{
+	int minor;
+	int peer_minor;
+	int rc;
+	struct ucred cred;
+	struct ucred_old cred_old;
+
+#if DEBUG == 1
+	static int call_count = 0;
+	printf("(uds) [%d] do_getsockopt_peercred() call_count=%d\n",
+					uds_minor(dev_m_in), ++call_count);
+#endif
+
+	minor = uds_minor(dev_m_in);
+
+	if (uds_fd_table[minor].peer == -1) {
+
+		if (uds_fd_table[minor].err == ECONNRESET) {
+			uds_fd_table[minor].err = 0;
+
+			return ECONNRESET;
+		} else {
+			return ENOTCONN;
+		}
+	}
+
+	peer_minor = uds_fd_table[minor].peer;
+
+	/* obtain the peer's credentials */
+	rc = getnucred(uds_fd_table[peer_minor].owner, &cred);
+	if (rc == -1) {
+		/* likely error: invalid endpoint / proc doesn't exist */
+		return errno;
+	}
+
+	/* copy to old structure */
+	cred_old.pid = cred.pid;
+	cred_old.uid = (short) cred.uid;
+	cred_old.gid = (char) cred.gid;
+
+	rc = sys_safecopyto(VFS_PROC_NR, (cp_grant_id_t) dev_m_in->IO_GRANT,
+		(vir_bytes) 0, (vir_bytes) &cred_old, sizeof(struct ucred_old),
+		D);
+
+	return rc ? EIO : OK;
+}
+
 int do_getsockopt_sndbuf(message *dev_m_in, message *dev_m_out)
 {
 	int minor;
diff --git a/servers/avfs/protect.c b/servers/avfs/protect.c
index 300a47d31..3f8c3838e 100644
--- a/servers/avfs/protect.c
+++ b/servers/avfs/protect.c
@@ -137,8 +137,11 @@ PUBLIC int do_chown()
 	/* Do not change uid/gid if new uid/gid is -1. */
 	uid = (m_in.owner == (uid_t)-1 ? vp->v_uid : m_in.owner);
 	gid = (m_in.group == (gid_t)-1 ? vp->v_gid : m_in.group);
-	if ((r = req_chown(vp->v_fs_e, vp->v_inode_nr, uid, gid,
-		      &new_mode)) == OK) {
+
+	if (uid > UID_MAX || gid > GID_MAX)
+		r = EINVAL;
+	else if ((r = req_chown(vp->v_fs_e, vp->v_inode_nr, uid, gid,
+				&new_mode)) == OK) {
 		vp->v_uid = uid;
 		vp->v_gid = gid;
 		vp->v_mode = new_mode;
@@ -156,7 +159,6 @@ PUBLIC int do_chown()
   return(r);
 }
 
-
 /*===========================================================================*
  *				do_umask				     *
  *===========================================================================*/
diff --git a/servers/mfs/cache.c b/servers/mfs/cache.c
index 5e9f00387..3a6898db7 100644
--- a/servers/mfs/cache.c
+++ b/servers/mfs/cache.c
@@ -352,7 +352,7 @@ int rw_flag;			/* READING or WRITING */
 	op = (rw_flag == READING ? MFS_DEV_READ : MFS_DEV_WRITE);
 	r = block_dev_io(op, dev, SELF_E, bp->b_data, pos, fs_block_size);
 	if (r < 0) {
-		printf("MFS(%d) I/O error on device %d/%d, block %lu\n",
+		printf("MFS(%d) I/O error on device %d/%d, block %u\n",
 		SELF_E, major(dev), minor(dev), bp->b_blocknr);
 		op_failed = 1;
 	} else if( (unsigned) r != fs_block_size) {
@@ -480,7 +480,7 @@ PUBLIC void rw_scattered(
 			/* Transfer failed. An error? Do we care? */
 			if (r != OK && i == 0) {
 				printf(
-				"MFS: I/O error on device %d/%d, block %lu\n",
+				"MFS: I/O error on device %d/%d, block %u\n",
 					major(dev), minor(dev), bp->b_blocknr);
 				bp->b_dev = NO_DEV;	/* invalidate block */
   				vm_forgetblocks();
diff --git a/servers/mfs/inode.h b/servers/mfs/inode.h
index f66532c3a..d6a527f6d 100644
--- a/servers/mfs/inode.h
+++ b/servers/mfs/inode.h
@@ -17,15 +17,15 @@
 #include <sys/queue.h>
 
 EXTERN struct inode {
-  mode_t i_mode;		/* file type, protection, etc. */
-  nlink_t i_nlinks;		/* how many links to this file */
-  uid_t i_uid;			/* user id of the file's owner */
-  gid_t i_gid;			/* group number */
-  off_t i_size;			/* current file size in bytes */
-  time_t i_atime;		/* time of last access (V2 only) */
-  time_t i_mtime;		/* when was file data last changed */
-  time_t i_ctime;		/* when was inode itself changed (V2 only)*/
-  zone_t i_zone[V2_NR_TZONES]; /* zone numbers for direct, ind, and dbl ind */
+  u16_t i_mode;		/* file type, protection, etc. */
+  u16_t i_nlinks;		/* how many links to this file */
+  u16_t i_uid;			/* user id of the file's owner */
+  u16_t i_gid;			/* group number */
+  i32_t i_size;			/* current file size in bytes */
+  u32_t i_atime;		/* time of last access (V2 only) */
+  u32_t i_mtime;		/* when was file data last changed */
+  u32_t i_ctime;		/* when was inode itself changed (V2 only)*/
+  u32_t i_zone[V2_NR_TZONES]; /* zone numbers for direct, ind, and dbl ind */
   
   /* The following items are not present on the disk. */
   dev_t i_dev;			/* which device is the inode on */
diff --git a/servers/mfs/main.c b/servers/mfs/main.c
index 76d7198ea..d0b3408f7 100644
--- a/servers/mfs/main.c
+++ b/servers/mfs/main.c
@@ -82,6 +82,8 @@ PUBLIC int main(int argc, char *argv[])
 		read_ahead(); /* do block read ahead */
       
   }
+
+  return(OK);
 }
 
 /*===========================================================================*
diff --git a/servers/mfs/stadir.c b/servers/mfs/stadir.c
index b7ec1c68d..93b05cceb 100644
--- a/servers/mfs/stadir.c
+++ b/servers/mfs/stadir.c
@@ -18,8 +18,8 @@ PRIVATE int copy_new_to_old_stat(endpoint_t who_e,
 	prevst.st_dev = st->st_dev;
 	prevst.st_ino = st->st_ino;
 	prevst.st_mode = st->st_mode;
-	prevst.st_uid = st->st_uid;
-	prevst.st_gid = st->st_gid;
+	prevst.st_uid = (short) st->st_uid;
+	prevst.st_gid = (short) st->st_gid;
 	prevst.st_size = st->st_size;
 	prevst.st_rdev = st->st_rdev;
 
@@ -63,7 +63,7 @@ PRIVATE int stat_inode(
   statbuf.st_mode = rip->i_mode;
   statbuf.st_nlink = rip->i_nlinks;
   statbuf.st_uid = rip->i_uid;
-  statbuf.st_gid = (short) rip->i_gid; /* FIXME: should become gid_t */
+  statbuf.st_gid = rip->i_gid;
   statbuf.st_rdev = (s ? (dev_t) rip->i_zone[0] : NO_DEV);
   statbuf.st_size = rip->i_size;
   statbuf.st_atime = rip->i_atime;
@@ -122,7 +122,7 @@ PUBLIC int fs_statvfs()
 
   scale = sp->s_log_zone_size;
 
-  blockstats(&st.f_blocks, &st.f_bfree, &used);
+  blockstats((u32_t *) &st.f_blocks, (u32_t *) &st.f_bfree, &used);
   st.f_bavail = st.f_bfree;
 
   st.f_bsize =  sp->s_block_size << scale;
diff --git a/servers/pfs/dev_uds.c b/servers/pfs/dev_uds.c
index c6033323e..015e5cfd5 100644
--- a/servers/pfs/dev_uds.c
+++ b/servers/pfs/dev_uds.c
@@ -886,6 +886,13 @@ PUBLIC int uds_ioctl(message *dev_m_in, message *dev_m_out)
 
 			break;
 
+		case NWIOGUDSPEERCREDOLD:
+
+			/* get peer endpoint -- getsockopt(SO_PEERCRED) */
+			rc = do_getsockopt_peercred_old(dev_m_in, dev_m_out);
+
+			break;
+
 		case NWIOSUDSTADDR:
 
 			/* set target address -- sendto() */
diff --git a/servers/pfs/proto.h b/servers/pfs/proto.h
index 9ba371c97..d6465e0ac 100644
--- a/servers/pfs/proto.h
+++ b/servers/pfs/proto.h
@@ -82,6 +82,8 @@ _PROTOTYPE( int do_getsockopt_sotype,
 				(message *dev_m_in, message *dev_m_out)	);
 _PROTOTYPE( int do_getsockopt_peercred,
 				(message *dev_m_in, message *dev_m_out)	);
+_PROTOTYPE( int do_getsockopt_peercred_old,
+				(message *dev_m_in, message *dev_m_out)	);
 _PROTOTYPE( int do_getsockopt_sndbuf,
 				(message *dev_m_in, message *dev_m_out)	);
 _PROTOTYPE( int do_setsockopt_sndbuf,
diff --git a/servers/pfs/uds.c b/servers/pfs/uds.c
index 81efd2ef3..7a1309cf4 100644
--- a/servers/pfs/uds.c
+++ b/servers/pfs/uds.c
@@ -1047,6 +1047,54 @@ PUBLIC int do_getsockopt_peercred(message *dev_m_in, message *dev_m_out)
 	return rc ? EIO : OK;
 }
 
+PUBLIC int do_getsockopt_peercred_old(message *dev_m_in, message *dev_m_out)
+{
+	int minor;
+	int peer_minor;
+	int rc;
+	struct ucred cred;
+	struct ucred_old cred_old;
+
+#if DEBUG == 1
+	static int call_count = 0;
+	printf("(uds) [%d] do_getsockopt_peercred() call_count=%d\n",
+					uds_minor(dev_m_in), ++call_count);
+#endif
+
+	minor = uds_minor(dev_m_in);
+
+	if (uds_fd_table[minor].peer == -1) {
+
+		if (uds_fd_table[minor].err == ECONNRESET) {
+			uds_fd_table[minor].err = 0;
+
+			return ECONNRESET;
+		} else {
+			return ENOTCONN;
+		}
+	}
+
+	peer_minor = uds_fd_table[minor].peer;
+
+	/* obtain the peer's credentials */
+	rc = getnucred(uds_fd_table[peer_minor].owner, &cred);
+	if (rc == -1) {
+		/* likely error: invalid endpoint / proc doesn't exist */
+		return errno;
+	}
+
+	/* copy to old structure */
+	cred_old.pid = cred.pid;
+	cred_old.uid = (short) cred.uid;
+	cred_old.gid = (char) cred.gid;
+
+	rc = sys_safecopyto(VFS_PROC_NR, (cp_grant_id_t) dev_m_in->IO_GRANT,
+		(vir_bytes) 0, (vir_bytes) &cred_old, sizeof(struct ucred_old),
+		D);
+
+	return rc ? EIO : OK;
+}
+
 int do_getsockopt_sndbuf(message *dev_m_in, message *dev_m_out) 
 {
 	int minor;
diff --git a/servers/pm/getset.c b/servers/pm/getset.c
index daf5b797f..a2e3e7f3a 100644
--- a/servers/pm/getset.c
+++ b/servers/pm/getset.c
@@ -18,37 +18,62 @@
  *===========================================================================*/
 PUBLIC int do_get()
 {
-/* Handle GETUID, GETGID, GETPID, GETPGRP, GETSID.
+/* Handle GETUID, GETGID, GETGROUPS, GETGROUPS_O, GETPID, GETPGRP, GETSID.
  */
 
   register struct mproc *rmp = mp;
-  int r;
+  int r, i;
   int ngroups;
+  char sgroups[NGROUPS_MAX];	/* XXX: Temp storage for GETGROUPS_O */
 
   switch(call_nr) {
-  	case GETGROUPS:
-  		ngroups = m_in.grp_no;
-  		if (ngroups > NGROUPS_MAX || ngroups < 0)
-  			return(EINVAL);
+	case GETGROUPS_O:
+		ngroups = m_in.grp_no;
+		if (ngroups > NGROUPS_MAX || ngroups < 0)
+			return(EINVAL);
 
-  		if (ngroups == 0) {
-  			r = rmp->mp_ngroups;
-  			break;
-  		}
+		if (ngroups == 0) {
+			r = rmp->mp_ngroups;
+			break;
+		}
 
-		if (ngroups < rmp->mp_ngroups) 
+		if (ngroups < rmp->mp_ngroups)
 			/* Asking for less groups than available */
 			return(EINVAL);
 	
+		for (i = 0; i < ngroups; i++)
+			sgroups[i] = (char) rmp->mp_sgroups[i];
 
-  		r = sys_datacopy(SELF, (vir_bytes) rmp->mp_sgroups, who_e,
-  			(vir_bytes) m_in.groupsp, ngroups * sizeof(gid_t));
+		r = sys_datacopy(SELF, (vir_bytes) &sgroups, who_e,
+			(vir_bytes) m_in.groupsp, ngroups * sizeof(char));
 
-  		if (r != OK) 
-  			return(r);
-  		
-  		r = rmp->mp_ngroups;
-  		break;
+		if (r != OK)
+			return(r);
+
+		r = rmp->mp_ngroups;
+		break;
+	case GETGROUPS:
+		ngroups = m_in.grp_no;
+		if (ngroups > NGROUPS_MAX || ngroups < 0)
+			return(EINVAL);
+
+		if (ngroups == 0) {
+			r = rmp->mp_ngroups;
+			break;
+		}
+
+		if (ngroups < rmp->mp_ngroups)
+			/* Asking for less groups than available */
+			return(EINVAL);
+
+		r = sys_datacopy(SELF, (vir_bytes) rmp->mp_sgroups, who_e,
+			(vir_bytes) m_in.groupsp, ngroups * sizeof(gid_t));
+
+		if (r != OK)
+			return(r);
+
+		r = rmp->mp_ngroups;
+		break;
 	case GETUID:
 		r = rmp->mp_realuid;
 		rmp->mp_reply.reply_res2 = rmp->mp_effuid;
@@ -97,6 +122,8 @@ PUBLIC int do_set()
   message m;
   int r, i;
   int ngroups;
+  char sgroups[NGROUPS_MAX];	/* XXX: Temp storage for SETGROUPS_O */
+
 
   switch(call_nr) {
 	case SETUID:
@@ -146,6 +173,40 @@ PUBLIC int do_set()
 		if (r != OK) 
 			return(r);
 
+		for (i = 0; i < ngroups; i++) {
+			if (rmp->mp_sgroups[i] > GID_MAX)
+				return(EINVAL);
+		}
+		for (i = ngroups; i < NGROUPS_MAX; i++) {
+			rmp->mp_sgroups[i] = 0;
+		}
+		rmp->mp_ngroups = ngroups;
+
+		m.m_type = PM_SETGROUPS;
+		m.PM_PROC = rmp->mp_endpoint;
+		m.PM_GROUP_NO = rmp->mp_ngroups;
+		m.PM_GROUP_ADDR = (char *) rmp->mp_sgroups;
+
+		break;
+	case SETGROUPS_O:
+		if (rmp->mp_effuid != SUPER_USER)
+			return(EPERM);
+
+		ngroups = m_in.grp_no;
+
+		if (ngroups > NGROUPS_MAX || ngroups < 0)
+			return(EINVAL);
+
+		if (m_in.groupsp == NULL)
+			return(EFAULT);
+
+		r = sys_datacopy(who_e, (vir_bytes) m_in.groupsp, SELF,
+			     (vir_bytes) &sgroups, ngroups * sizeof(char));
+		if (r != OK)
+			return(r);
+
+		for (i = 0; i < ngroups; i++)
+			rmp->mp_sgroups[i] = (gid_t) sgroups[i];
 		for (i = ngroups; i < NGROUPS_MAX; i++)
 			rmp->mp_sgroups[i] = 0;
 		rmp->mp_ngroups = ngroups;
@@ -153,7 +214,7 @@ PUBLIC int do_set()
 		m.m_type = PM_SETGROUPS;
 		m.PM_PROC = rmp->mp_endpoint;
 		m.PM_GROUP_NO = rmp->mp_ngroups;
-		m.PM_GROUP_ADDR = rmp->mp_sgroups;
+		m.PM_GROUP_ADDR = (char *) rmp->mp_sgroups;
 
 		break;
 	case SETSID:
diff --git a/servers/pm/misc.c b/servers/pm/misc.c
index 3549eb3af..b6adec1c7 100644
--- a/servers/pm/misc.c
+++ b/servers/pm/misc.c
@@ -316,15 +316,14 @@ PUBLIC int do_getepinfo()
   endpoint_t ep;
 
   /* This call should be moved to DS. */
-  if (mp->mp_effuid != 0)
-  {
-	printf("PM: unauthorized call of do_getepinfo by proc %d\n",
+  if (mp->mp_effuid != 0) {
+	printf("PM: unauthorized call of do_getepinfo_o by proc %d\n",
 		mp->mp_endpoint);
 	sys_sysctl_stacktrace(mp->mp_endpoint);
 	return EPERM;
   }
 
-  ep= m_in.PM_ENDPT;
+  ep = m_in.PM_ENDPT;
 
   for (rmp = &mproc[0]; rmp < &mproc[NR_PROCS]; rmp++) {
 	if ((rmp->mp_flags & IN_USE) && (rmp->mp_endpoint == ep)) {
@@ -332,7 +331,37 @@ PUBLIC int do_getepinfo()
 		mp->mp_reply.reply_res3 = rmp->mp_effgid;
 		return(rmp->mp_pid);
 	}
-  } 
+  }
+
+  /* Process not found */
+  return(ESRCH);
+}
+
+/*===========================================================================*
+ *				do_getepinfo_o			             *
+ *===========================================================================*/
+PUBLIC int do_getepinfo_o()
+{
+  register struct mproc *rmp;
+  endpoint_t ep;
+
+  /* This call should be moved to DS. */
+  if (mp->mp_effuid != 0) {
+	printf("PM: unauthorized call of do_getepinfo_o by proc %d\n",
+		mp->mp_endpoint);
+	sys_sysctl_stacktrace(mp->mp_endpoint);
+	return EPERM;
+  }
+
+  ep = m_in.PM_ENDPT;
+
+  for (rmp = &mproc[0]; rmp < &mproc[NR_PROCS]; rmp++) {
+	if ((rmp->mp_flags & IN_USE) && (rmp->mp_endpoint == ep)) {
+		mp->mp_reply.reply_res2 = (short) rmp->mp_effuid;
+		mp->mp_reply.reply_res3 = (char) rmp->mp_effgid;
+		return(rmp->mp_pid);
+	}
+  }
 
   /* Process not found */
   return(ESRCH);
diff --git a/servers/pm/proto.h b/servers/pm/proto.h
index 9eb2bd429..e2ab0528c 100644
--- a/servers/pm/proto.h
+++ b/servers/pm/proto.h
@@ -62,6 +62,7 @@ _PROTOTYPE( int do_getsysinfo, (void)					);
 _PROTOTYPE( int do_getsysinfo_up, (void)					);
 _PROTOTYPE( int do_getprocnr, (void)					);
 _PROTOTYPE( int do_getepinfo, (void)					);
+_PROTOTYPE( int do_getepinfo_o, (void)					);
 _PROTOTYPE( int do_svrctl, (void)					);
 _PROTOTYPE( int do_getsetpriority, (void)				);
 
diff --git a/servers/pm/table.c b/servers/pm/table.c
index 6a69002ec..e81a3ca6a 100644
--- a/servers/pm/table.c
+++ b/servers/pm/table.c
@@ -15,7 +15,7 @@ _PROTOTYPE (int (*call_vec[]), (void) ) = {
 	do_exit,	/*  1 = exit	*/
 	do_fork,	/*  2 = fork	*/
 	no_sys,		/*  3 = read	*/
-	no_sys,		/*  4 = write	*/
+	no_sys, 	/*  4 = write	*/
 	no_sys,		/*  5 = open	*/
 	no_sys,		/*  6 = close	*/
 	do_waitpid,	/*  7 = wait	*/
@@ -42,11 +42,11 @@ _PROTOTYPE (int (*call_vec[]), (void) ) = {
 	no_sys,		/* 28 = fstat	*/
 	do_pause,	/* 29 = pause	*/
 	no_sys,		/* 30 = utime	*/
-	no_sys,		/* 31 = (stty)	*/
-	no_sys,		/* 32 = (gtty)	*/
+	do_getepinfo,	/* 31 = getepinfo */
+	do_set, 	/* 32 = setgroups */
 	no_sys,		/* 33 = access	*/
-	no_sys,		/* 34 = (nice)	*/
-	no_sys,		/* 35 = (ftime)	*/
+	do_get,		/* 34 = getgroups */
+	no_sys,		/* 35 = unused	*/
 	no_sys,		/* 36 = sync	*/
 	do_kill,	/* 37 = kill	*/
 	no_sys,		/* 38 = rename	*/
@@ -55,19 +55,19 @@ _PROTOTYPE (int (*call_vec[]), (void) ) = {
 	no_sys,		/* 41 = dup	*/
 	no_sys,		/* 42 = pipe	*/
 	do_times,	/* 43 = times	*/
-	no_sys,		/* 44 = (prof)	*/
+	no_sys,		/* 44 = unused	*/
 	no_sys,		/* 45 = unused	*/
 	do_set,		/* 46 = setgid	*/
 	do_get,		/* 47 = getgid	*/
 	no_sys,		/* 48 = (signal)*/
 	no_sys,		/* 49 = unused	*/
 	no_sys,		/* 50 = lstat	*/
-	no_sys,		/* 51 = (acct)	*/
-	no_sys,		/* 52 = (phys)	*/
-	no_sys,		/* 53 = (lock)	*/
+	no_sys,		/* 51 = unused	*/
+	no_sys,		/* 52 = unused	*/
+	no_sys,		/* 53 = unused	*/
 	no_sys,		/* 54 = ioctl	*/
 	no_sys,		/* 55 = fcntl	*/
-	no_sys,		/* 56 = (mpx)	*/
+	no_sys,		/* 56 = unused	*/
 	no_sys,		/* 57 = unused	*/
 	no_sys,		/* 58 = unused	*/
 	do_exec,	/* 59 = execve	*/
@@ -119,7 +119,7 @@ _PROTOTYPE (int (*call_vec[]), (void) ) = {
 	do_getprocnr,	/* 104 = getprocnr */
 	no_sys,		/* 105 = unused */
 	no_sys,		/* 106 = unused */
-	do_getepinfo,	/* 107 = getepinfo */
+	do_getepinfo_o,	/* 107 = getepinfo XXX: old implementation*/
 	do_adddma,	/* 108 = adddma */
 	do_deldma,	/* 109 = deldma */
 	do_getdma,	/* 110 = getdma */
diff --git a/servers/vfs/main.c b/servers/vfs/main.c
index 79a3d5773..55447a954 100644
--- a/servers/vfs/main.c
+++ b/servers/vfs/main.c
@@ -572,7 +572,7 @@ PRIVATE void service_pm()
 
 	break;
   case PM_SETGROUPS:
-	pm_setgroups(m_in.PM_PROC, m_in.PM_GROUP_NO, m_in.PM_GROUP_ADDR);
+	pm_setgroups(m_in.PM_PROC, m_in.PM_GROUP_NO, (gid_t *) m_in.PM_GROUP_ADDR);
 
 	m_out.m_type = PM_SETGROUPS_REPLY;
 	m_out.PM_PROC = m_in.PM_PROC;
diff --git a/servers/vfs/protect.c b/servers/vfs/protect.c
index 558cf4f90..01a0555d4 100644
--- a/servers/vfs/protect.c
+++ b/servers/vfs/protect.c
@@ -105,11 +105,14 @@ PUBLIC int do_chown()
   }
 
   if (r == OK) {
-  	/* Do not change uid/gid if new uid/gid is -1. */
-  	uid = (m_in.owner == (uid_t)-1 ? vp->v_uid : m_in.owner);
-  	gid = (m_in.group == (gid_t)-1 ? vp->v_gid : m_in.group);
-	if ((r = req_chown(vp->v_fs_e, vp->v_inode_nr, uid, gid,
-		      &new_mode)) == OK) {
+	/* Do not change uid/gid if new uid/gid is -1. */
+	uid = (m_in.owner == (uid_t)-1 ? vp->v_uid : m_in.owner);
+	gid = (m_in.group == (gid_t)-1 ? vp->v_gid : m_in.group);
+
+	if (uid > UID_MAX || gid > GID_MAX)
+		r = EINVAL;
+	else if ((r = req_chown(vp->v_fs_e, vp->v_inode_nr, uid, gid,
+				&new_mode)) == OK) {
 	  	vp->v_uid = uid;
 		vp->v_gid = gid;
 		vp->v_mode = new_mode;
diff --git a/servers/vfs/table.c b/servers/vfs/table.c
index 0f05fd528..029e7a45c 100644
--- a/servers/vfs/table.c
+++ b/servers/vfs/table.c
@@ -46,11 +46,11 @@ PUBLIC _PROTOTYPE (int (*call_vec[]), (void) ) = {
 	do_fstat,	/* 28 = fstat (prev)*/
 	no_sys,		/* 29 = pause	*/
 	do_utime,	/* 30 = utime	*/
-	no_sys,		/* 31 = (stty)	*/
-	no_sys,		/* 32 = (gtty)	*/
+	no_sys,		/* 31 = unused	*/
+	no_sys,		/* 32 = unused	*/
 	do_access,	/* 33 = access	*/
-	no_sys,		/* 34 = (nice)	*/
-	no_sys,		/* 35 = (ftime)	*/
+	no_sys,		/* 34 = unused	*/
+	no_sys,		/* 35 = unused	*/
 	do_sync,	/* 36 = sync	*/
 	no_sys,		/* 37 = kill	*/
 	do_rename,	/* 38 = rename	*/
@@ -59,19 +59,19 @@ PUBLIC _PROTOTYPE (int (*call_vec[]), (void) ) = {
 	do_dup,		/* 41 = dup	*/
 	do_pipe,	/* 42 = pipe	*/
 	no_sys,		/* 43 = times	*/
-	no_sys,		/* 44 = (prof)	*/
+	no_sys,		/* 44 = unused	*/
 	do_slink,	/* 45 = symlink	*/
 	no_sys,		/* 46 = (setgid)*/
 	no_sys,		/* 47 = getgid	*/
 	no_sys,		/* 48 = (signal)*/
 	do_rdlink,	/* 49 = readlink*/
 	do_lstat,	/* 50 = lstat (prev)*/
-	no_sys,		/* 51 = (acct)	*/
-	no_sys,		/* 52 = (phys)	*/
-	no_sys,		/* 53 = (lock)	*/
+	no_sys,		/* 51 = unused	*/
+	no_sys,		/* 52 = unused	*/
+	no_sys,		/* 53 = unused	*/
 	do_ioctl,	/* 54 = ioctl	*/
 	do_fcntl,	/* 55 = fcntl	*/
-	no_sys,		/* 56 = (mpx)	*/
+	no_sys,		/* 56 = unused	*/
 	do_fslogin,	/* 57 = FS proc login */
 	no_sys,		/* 58 = unused	*/
 	no_sys,		/* 59 = (execve)*/
diff --git a/test/test46.c b/test/test46.c
index 7d0d0ac16..35b962c22 100644
--- a/test/test46.c
+++ b/test/test46.c
@@ -28,8 +28,7 @@ _PROTOTYPE( void group_test_4, (void)					);
 _PROTOTYPE( void group_test_5, (void)					);
 _PROTOTYPE( int dotest, (void (*testfunc)(void))				);
 
-int subtest = -1, errorct = 0;
-#define ERROR_MAX 5
+#define MAX_ERROR 5
 #define IMAGINARY_GID 100
 #define IMAGINARY_GID_STR "100"
 #define IMAGINARY_UID 101
@@ -38,12 +37,14 @@ int subtest = -1, errorct = 0;
 			  setgid((IMAGINARY_GID) + 1 ); \
 			  setuid(IMAGINARY_UID); \
 			} while(0)
+#include "common.c"
+
+int subtest = -1, errorct = 0;
 
 int main(int argc, char *argv[])
 {
   int superuser;
-  printf("Test 46 ");
-  fflush(stdout);
+  start(46);
 
   superuser = (geteuid() == 0);
 
@@ -58,13 +59,7 @@ int main(int argc, char *argv[])
   api_test();	/* Perform some very basic API tests */
   group_test();	/* Perform some tests that mimic actual use */
 
-  if(errorct > 0) {
-	printf("%d error(s)\n", errorct);
-	return(errorct);
-  }
-
-  printf("ok\n");
-  return(0);
+  quit();
 }
 
 void limit_test() {
@@ -115,8 +110,8 @@ void api_test() {
 
   /* Let's invent some imaginary groups */
 #define START_GID 20001
-  for (i = START_GID; i < START_GID + ngroups_max; i++)
-	grouplist[i - START_GID] = i;
+  for (i = 0; i < ngroups_max; i++)
+	grouplist[i] = i + START_GID;
 
   /* Normal usage */
   if (setgroups(ngroups_max, grouplist) != 0) e(1);
@@ -184,6 +179,11 @@ void api_test() {
 	}
   }
 
+  /* Try to set too high a group ID */
+  grouplist2[0] = GID_MAX + 1;	/* Out of range */
+  if (setgroups(1, grouplist2) == 0) e(23);
+  if (errno != EINVAL) e(24);
+
   free(grouplist);
   free(grouplist2);
 }
@@ -343,13 +343,3 @@ void group_test_5() {
   dirp = opendir("DIR_046/sub");
   exit(dirp != NULL); /* If not NULL, we were able to access it */
 }
-
-void e(int error_no) {
-  printf("Subtest %d, error %d\n", subtest, error_no);
-
-  if (errorct++ > ERROR_MAX) {
-	printf("Too many errors, test aborted\n");
-	exit(1);
-  }
-}
-