--- embedaddon/sudo/plugins/sudoers/set_perms.c	2012/02/21 16:23:02	1.1
+++ embedaddon/sudo/plugins/sudoers/set_perms.c	2014/06/15 16:12:54	1.1.1.6
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1994-1996,1998-2011 Todd C. Miller <Todd.Miller@courtesan.com>
+ * Copyright (c) 1994-1996,1998-2013 Todd C. Miller <Todd.Miller@courtesan.com>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -21,7 +21,6 @@
 #include <config.h>
 
 #include <sys/types.h>
-#include <sys/param.h>
 #include <sys/stat.h>
 #include <stdio.h>
 #ifdef STDC_HEADERS
@@ -41,6 +40,9 @@
 #ifdef HAVE_UNISTD_H
 # include <unistd.h>
 #endif /* HAVE_UNISTD_H */
+#ifdef _AIX
+# include <sys/id.h>
+#endif
 #include <pwd.h>
 #include <errno.h>
 #include <grp.h>
@@ -50,7 +52,9 @@
 /*
  * Prototypes
  */
+#if defined(HAVE_SETRESUID) || defined(HAVE_SETREUID) || defined(HAVE_SETEUID)
 static struct group_list *runas_setgroups(void);
+#endif
 
 /*
  * We keep track of the current permisstions and use a stack to restore
@@ -59,12 +63,12 @@ static struct group_list *runas_setgroups(void);
 struct perm_state {
     uid_t ruid;
     uid_t euid;
-#ifdef HAVE_SETRESUID
+#if defined(HAVE_SETRESUID) || defined(ID_SAVED)
     uid_t suid;
 #endif
     gid_t rgid;
     gid_t egid;
-#ifdef HAVE_SETRESUID
+#if defined(HAVE_SETRESUID) || defined(ID_SAVED)
     gid_t sgid;
 #endif
     struct group_list *grlist;
@@ -75,20 +79,29 @@ static struct perm_state perm_stack[PERM_STACK_MAX];
 static int perm_stack_depth = 0;
 
 #undef ID
-#define ID(x) (state->x == ostate->x ? -1 : state->x)
+#define ID(x) (state->x == ostate->x ? (uid_t)-1 : state->x)
 #undef OID
-#define OID(x) (ostate->x == state->x ? -1 : ostate->x)
+#define OID(x) (ostate->x == state->x ? (uid_t)-1 : ostate->x)
 
 void
 rewind_perms(void)
 {
-    while (perm_stack_depth > 1)
-	restore_perms();
-    grlist_delref(perm_stack[0].grlist);
+    debug_decl(rewind_perms, SUDO_DEBUG_PERMS)
+
+    if (perm_stack_depth != 0) {
+	while (perm_stack_depth > 1)
+	    restore_perms();
+	sudo_grlist_delref(perm_stack[0].grlist);
+    }
+
+    debug_return;
 }
 
-#ifdef HAVE_SETRESUID
+#if defined(HAVE_SETRESUID)
 
+#define UID_CHANGED (state->ruid != ostate->ruid || state->euid != ostate->euid || state->suid != ostate->suid)
+#define GID_CHANGED (state->rgid != ostate->rgid || state->egid != ostate->egid || state->sgid != ostate->sgid)
+
 /*
  * Set real and effective and saved uids and gids based on perm.
  * We always retain a saved uid of 0 unless we are headed for an exec().
@@ -99,14 +112,16 @@ int
 set_perms(int perm)
 {
     struct perm_state *state, *ostate = NULL;
-    const char *errstr;
+    char errbuf[1024];
+    const char *errstr = errbuf;
     int noexit;
+    debug_decl(set_perms, SUDO_DEBUG_PERMS)
 
     noexit = ISSET(perm, PERM_NOEXIT);
     CLR(perm, PERM_MASK);
 
     if (perm_stack_depth == PERM_STACK_MAX) {
-	errstr = _("perm stack overflow");
+	errstr = N_("perm stack overflow");
 	errno = EINVAL;
 	goto bad;
     }
@@ -114,13 +129,11 @@ set_perms(int perm)
     state = &perm_stack[perm_stack_depth];
     if (perm != PERM_INITIAL) {
 	if (perm_stack_depth == 0) {
-	    errstr = _("perm stack underflow");
+	    errstr = N_("perm stack underflow");
 	    errno = EINVAL;
 	    goto bad;
 	}
 	ostate = &perm_stack[perm_stack_depth - 1];
-	if (memcmp(state, ostate, sizeof(*state)) == 0)
-	    goto done;
     }
 
     switch (perm) {
@@ -128,12 +141,12 @@ set_perms(int perm)
 	/* Stash initial state */
 #ifdef HAVE_GETRESUID
 	if (getresuid(&state->ruid, &state->euid, &state->suid)) {
-	    errstr = "getresuid";
+	    errstr = "PERM_INITIAL: getresuid";
 	    goto bad;
 
 	}
 	if (getresgid(&state->rgid, &state->egid, &state->sgid)) {
-	    errstr = "getresgid";
+	    errstr = "PERM_INITIAL: getresgid";
 	    goto bad;
 	}
 #else
@@ -146,45 +159,73 @@ set_perms(int perm)
 	state->sgid = state->egid; /* in case we are setgid */
 #endif
 	state->grlist = user_group_list;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_INITIAL: "
+	    "ruid: %d, euid: %d, suid: %d, rgid: %d, egid: %d, sgid: %d",
+	    __func__, (int)state->ruid, (int)state->euid, (int)state->suid,
+	    (int)state->rgid, (int)state->egid, (int)state->sgid);
 	break;
 
     case PERM_ROOT:
 	state->ruid = ROOT_UID;
 	state->euid = ROOT_UID;
 	state->suid = ROOT_UID;
-	if (setresuid(ID(ruid), ID(euid), ID(suid))) {
-	    errstr = "setresuid(ROOT_UID, ROOT_UID, ROOT_UID)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_ROOT: uid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->ruid, (int)ostate->euid, (int)ostate->suid,
+	    (int)state->ruid, (int)state->euid, (int)state->suid);
+	if (UID_CHANGED && setresuid(ID(ruid), ID(euid), ID(suid))) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_ROOT: setresuid(%d, %d, %d)",
+		ID(ruid), ID(euid), ID(suid));
 	    goto bad;
 	}
-	state->rgid = -1;
-	state->egid = -1;
-	state->sgid = -1;
+	state->rgid = ostate->rgid;
+	state->egid = ROOT_GID;
+	state->sgid = ostate->sgid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_ROOT: gid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->rgid, (int)ostate->egid, (int)ostate->sgid,
+	    (int)state->rgid, (int)state->egid, (int)state->sgid);
+	if (GID_CHANGED && setresgid(ID(rgid), ID(egid), ID(sgid))) {
+	    errstr = N_("unable to change to root gid");
+	    goto bad;
+	}
 	state->grlist = ostate->grlist;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 	break;
 
     case PERM_USER:
-	state->rgid = -1;
+	state->rgid = ostate->rgid;
 	state->egid = user_gid;
-	state->sgid = -1;
-	if (setresgid(-1, ID(egid), -1)) {
-	    errstr = "setresgid(-1, user_gid, -1)";
+	state->sgid = ostate->sgid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_USER: gid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->rgid, (int)ostate->egid, (int)ostate->sgid,
+	    (int)state->rgid, (int)state->egid, (int)state->sgid);
+	if (GID_CHANGED && setresgid(ID(rgid), ID(egid), ID(sgid))) {
+	    snprintf(errbuf, sizeof(errbuf), "PERM_USER: setresgid(%d, %d, %d)",
+		ID(rgid), ID(egid), ID(sgid));
 	    goto bad;
 	}
 	state->grlist = user_group_list;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 	if (state->grlist != ostate->grlist) {
 	    if (sudo_setgroups(state->grlist->ngids, state->grlist->gids)) {
-		errstr = "setgroups()";
+		errstr = "PERM_USER: setgroups";
 		goto bad;
 	    }
 	}
 	state->ruid = user_uid;
 	state->euid = user_uid;
 	state->suid = ROOT_UID;
-	if (setresuid(ID(ruid), ID(euid), ID(suid))) {
-	    errstr = "setresuid(user_uid, user_uid, ROOT_UID)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_USER: uid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->ruid, (int)ostate->euid, (int)ostate->suid,
+	    (int)state->ruid, (int)state->euid, (int)state->suid);
+	if (UID_CHANGED && setresuid(ID(ruid), ID(euid), ID(suid))) {
+	    snprintf(errbuf, sizeof(errbuf), "PERM_USER: setresuid(%d, %d, %d)",
+		ID(ruid), ID(euid), ID(suid));
 	    goto bad;
 	}
 	break;
@@ -194,55 +235,81 @@ set_perms(int perm)
 	state->rgid = user_gid;
 	state->egid = user_gid;
 	state->sgid = user_gid;
-	if (setresgid(ID(rgid), ID(egid), ID(sgid))) {
-	    errstr = "setresgid(user_gid, user_gid, user_gid)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_FULL_USER: gid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->rgid, (int)ostate->egid, (int)ostate->sgid,
+	    (int)state->rgid, (int)state->egid, (int)state->sgid);
+	if (GID_CHANGED && setresgid(ID(rgid), ID(egid), ID(sgid))) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_FULL_USER: setresgid(%d, %d, %d)",
+		ID(rgid), ID(egid), ID(sgid));
 	    goto bad;
 	}
 	state->grlist = user_group_list;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 	if (state->grlist != ostate->grlist) {
 	    if (sudo_setgroups(state->grlist->ngids, state->grlist->gids)) {
-		errstr = "setgroups()";
+		errstr = "PERM_FULL_USER: setgroups";
 		goto bad;
 	    }
 	}
 	state->ruid = user_uid;
 	state->euid = user_uid;
 	state->suid = user_uid;
-	if (setresuid(ID(ruid), ID(euid), ID(suid))) {
-	    errstr = "setresuid(user_uid, user_uid, user_uid)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_FULL_USER: uid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->ruid, (int)ostate->euid, (int)ostate->suid,
+	    (int)state->ruid, (int)state->euid, (int)state->suid);
+	if (UID_CHANGED && setresuid(ID(ruid), ID(euid), ID(suid))) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_FULL_USER: setresuid(%d, %d, %d)",
+		ID(ruid), ID(euid), ID(suid));
 	    goto bad;
 	}
 	break;
 
     case PERM_RUNAS:
-	state->rgid = -1;
+	state->rgid = ostate->rgid;
 	state->egid = runas_gr ? runas_gr->gr_gid : runas_pw->pw_gid;
-	state->sgid = -1;
-	if (setresgid(-1, ID(egid), -1)) {
-	    errstr = _("unable to change to runas gid");
+	state->sgid = ostate->sgid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_RUNAS: gid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->rgid, (int)ostate->egid, (int)ostate->sgid,
+	    (int)state->rgid, (int)state->egid, (int)state->sgid);
+	if (GID_CHANGED && setresgid(ID(rgid), ID(egid), ID(sgid))) {
+	    errstr = N_("unable to change to runas gid");
 	    goto bad;
 	}
 	state->grlist = runas_setgroups();
-	state->ruid = -1;
+	state->ruid = ostate->ruid;
 	state->euid = runas_pw ? runas_pw->pw_uid : user_uid;
-	state->suid = -1;
-	if (setresuid(-1, ID(euid), -1)) {
-	    errstr = _("unable to change to runas uid");
+	state->suid = ostate->suid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_RUNAS: uid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->ruid, (int)ostate->euid, (int)ostate->suid,
+	    (int)state->ruid, (int)state->euid, (int)state->suid);
+	if (UID_CHANGED && setresuid(ID(ruid), ID(euid), ID(suid))) {
+	    errstr = N_("unable to change to runas uid");
 	    goto bad;
 	}
 	break;
 
     case PERM_SUDOERS:
 	state->grlist = ostate->grlist;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 
 	/* assumes euid == ROOT_UID, ruid == user */
-	state->rgid = -1;
+	state->rgid = ostate->rgid;
 	state->egid = sudoers_gid;
-	state->sgid = -1;
-	if (setresgid(-1, ID(egid), -1))
-	    error(1, _("unable to change to sudoers gid"));
+	state->sgid = ostate->sgid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_SUDOERS: gid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->rgid, (int)ostate->egid, (int)ostate->sgid,
+	    (int)state->rgid, (int)state->egid, (int)state->sgid);
+	if (GID_CHANGED && setresgid(ID(rgid), ID(egid), ID(sgid))) {
+	    errstr = N_("unable to change to sudoers gid");
+	    goto bad;
+	}
 
 	state->ruid = ROOT_UID;
 	/*
@@ -250,42 +317,54 @@ set_perms(int perm)
 	 * we use a non-zero uid in order to avoid NFS lossage.
 	 * Using uid 1 is a bit bogus but should work on all OS's.
 	 */
-	if (sudoers_uid == ROOT_UID && (sudoers_mode & 040))
+	if (sudoers_uid == ROOT_UID && (sudoers_mode & S_IRGRP))
 	    state->euid = 1;
 	else
 	    state->euid = sudoers_uid;
 	state->suid = ROOT_UID;
-	if (setresuid(ID(ruid), ID(euid), ID(suid))) {
-	    errstr = "setresuid(ROOT_UID, SUDOERS_UID, ROOT_UID)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_SUDOERS: uid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->ruid, (int)ostate->euid, (int)ostate->suid,
+	    (int)state->ruid, (int)state->euid, (int)state->suid);
+	if (UID_CHANGED && setresuid(ID(ruid), ID(euid), ID(suid))) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_SUDOERS: setresuid(%d, %d, %d)",
+		ID(ruid), ID(euid), ID(suid));
 	    goto bad;
 	}
 	break;
 
     case PERM_TIMESTAMP:
 	state->grlist = ostate->grlist;
-	grlist_addref(state->grlist);
-	state->rgid = -1;
-	state->egid = -1;
-	state->sgid = -1;
+	sudo_grlist_addref(state->grlist);
+	state->rgid = ostate->rgid;
+	state->egid = ostate->egid;
+	state->sgid = ostate->sgid;
 	state->ruid = ROOT_UID;
 	state->euid = timestamp_uid;
 	state->suid = ROOT_UID;
-	if (setresuid(ID(ruid), ID(euid), ID(suid))) {
-	    errstr = "setresuid(ROOT_UID, timestamp_uid, ROOT_UID)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_TIMESTAMP: uid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->ruid, (int)ostate->euid, (int)ostate->suid,
+	    (int)state->ruid, (int)state->euid, (int)state->suid);
+	if (UID_CHANGED && setresuid(ID(ruid), ID(euid), ID(suid))) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_TIMESTAMP: setresuid(%d, %d, %d)",
+		ID(ruid), ID(euid), ID(suid));
 	    goto bad;
 	}
 	break;
     }
 
-done:
     perm_stack_depth++;
-    return 1;
+    debug_return_bool(1);
 bad:
-    /* XXX - better warnings inline */
-    warningx("%s: %s", errstr,
-	errno == EAGAIN ? _("too many processes") : strerror(errno));
+    if (errno == EAGAIN)
+	warningx(U_("%s: %s"), U_(errstr), U_("too many processes"));
+    else
+	warning("%s", U_(errstr));
     if (noexit)
-	return 0;
+	debug_return_bool(0);
     exit(1);
 }
 
@@ -293,16 +372,24 @@ void
 restore_perms(void)
 {
     struct perm_state *state, *ostate;
+    debug_decl(restore_perms, SUDO_DEBUG_PERMS)
 
     if (perm_stack_depth < 2)
-	return;
+	debug_return;
 
     state = &perm_stack[perm_stack_depth - 1];
     ostate = &perm_stack[perm_stack_depth - 2];
     perm_stack_depth--;
 
+    sudo_debug_printf(SUDO_DEBUG_INFO, "%s: uid: [%d, %d, %d] -> [%d, %d, %d]",
+	__func__, (int)state->ruid, (int)state->euid, (int)state->suid,
+	(int)ostate->ruid, (int)ostate->euid, (int)ostate->suid);
+    sudo_debug_printf(SUDO_DEBUG_INFO, "%s: gid: [%d, %d, %d] -> [%d, %d, %d]",
+	__func__, (int)state->rgid, (int)state->egid, (int)state->sgid,
+	(int)ostate->rgid, (int)ostate->egid, (int)ostate->sgid);
+
     /* XXX - more cases here where euid != ruid */
-    if (OID(euid) == ROOT_UID && state->euid != ROOT_UID) {
+    if (OID(euid) == ROOT_UID) {
 	if (setresuid(-1, ROOT_UID, -1)) {
 	    warning("setresuid() [%d, %d, %d] -> [%d, %d, %d]",
 		(int)state->ruid, (int)state->euid, (int)state->suid,
@@ -328,34 +415,38 @@ restore_perms(void)
 	    goto bad;
 	}
     }
-    grlist_delref(state->grlist);
-    return;
+    sudo_grlist_delref(state->grlist);
+    debug_return;
 
 bad:
     exit(1);
 }
 
-#else
-# ifdef HAVE_SETREUID
+#elif defined(_AIX) && defined(ID_SAVED)
 
+#define UID_CHANGED (state->ruid != ostate->ruid || state->euid != ostate->euid || state->suid != ostate->suid)
+#define GID_CHANGED (state->rgid != ostate->rgid || state->egid != ostate->egid || state->sgid != ostate->sgid)
+
 /*
- * Set real and effective uids and gids based on perm.
- * We always retain a real or effective uid of ROOT_UID unless
- * we are headed for an exec().
+ * Set real and effective and saved uids and gids based on perm.
+ * We always retain a saved uid of 0 unless we are headed for an exec().
+ * We only flip the effective gid since it only changes for PERM_SUDOERS.
  * This version of set_perms() works fine with the "stay_setuid" option.
  */
 int
 set_perms(int perm)
 {
     struct perm_state *state, *ostate = NULL;
-    const char *errstr;
+    char errbuf[1024];
+    const char *errstr = errbuf;
     int noexit;
+    debug_decl(set_perms, SUDO_DEBUG_PERMS)
 
     noexit = ISSET(perm, PERM_NOEXIT);
     CLR(perm, PERM_MASK);
 
     if (perm_stack_depth == PERM_STACK_MAX) {
-	errstr = _("perm stack overflow");
+	errstr = N_("perm stack overflow");
 	errno = EINVAL;
 	goto bad;
     }
@@ -363,66 +454,495 @@ set_perms(int perm)
     state = &perm_stack[perm_stack_depth];
     if (perm != PERM_INITIAL) {
 	if (perm_stack_depth == 0) {
-	    errstr = _("perm stack underflow");
+	    errstr = N_("perm stack underflow");
 	    errno = EINVAL;
 	    goto bad;
 	}
 	ostate = &perm_stack[perm_stack_depth - 1];
-	if (memcmp(state, ostate, sizeof(*state)) == 0)
-	    goto done;
     }
 
     switch (perm) {
     case PERM_INITIAL:
 	/* Stash initial state */
+	state->ruid = getuidx(ID_REAL);
+	state->euid = getuidx(ID_EFFECTIVE);
+	state->suid = getuidx(ID_SAVED);
+	state->rgid = getgidx(ID_REAL);
+	state->egid = getgidx(ID_EFFECTIVE);
+	state->sgid = getgidx(ID_SAVED);
+	state->grlist = user_group_list;
+	sudo_grlist_addref(state->grlist);
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_INITIAL: "
+	    "ruid: %d, euid: %d, suid: %d, rgid: %d, egid: %d, sgid: %d",
+	    __func__, (unsigned int)state->ruid, (unsigned int)state->euid,
+	    (unsigned int)state->suid, (unsigned int)state->rgid,
+	    (unsigned int)state->egid, (unsigned int)state->sgid);
+	break;
+
+    case PERM_ROOT:
+	state->ruid = ROOT_UID;
+	state->euid = ROOT_UID;
+	state->suid = ROOT_UID;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_ROOT: uid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->ruid, (int)ostate->euid, (int)ostate->suid,
+	    (int)state->ruid, (int)state->euid, (int)state->suid);
+	if (UID_CHANGED && setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, ROOT_UID)) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_ROOT: setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, %d)",
+		ROOT_UID);
+	    goto bad;
+	}
+	state->rgid = ostate->rgid;
+	state->egid = ROOT_GID;
+	state->sgid = ostate->sgid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_ROOT: gid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->rgid, (int)ostate->egid, (int)ostate->sgid,
+	    (int)state->rgid, (int)state->egid, (int)state->sgid);
+	if (GID_CHANGED && setgidx(ID_EFFECTIVE, ROOT_GID)) {
+	    errstr = N_("unable to change to root gid");
+	    goto bad;
+	}
+	state->grlist = ostate->grlist;
+	sudo_grlist_addref(state->grlist);
+	break;
+
+    case PERM_USER:
+	state->rgid = ostate->rgid;
+	state->egid = user_gid;
+	state->sgid = ostate->sgid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_USER: gid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->rgid, (int)ostate->egid, (int)ostate->sgid,
+	    (int)state->rgid, (int)state->egid, (int)state->sgid);
+	if (GID_CHANGED && setgidx(ID_EFFECTIVE, user_gid)) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_USER: setgidx(ID_EFFECTIVE, %d)", user_gid);
+	    goto bad;
+	}
+	state->grlist = user_group_list;
+	sudo_grlist_addref(state->grlist);
+	if (state->grlist != ostate->grlist) {
+	    if (sudo_setgroups(state->grlist->ngids, state->grlist->gids)) {
+		errstr = "PERM_USER: setgroups";
+		goto bad;
+	    }
+	}
+	state->ruid = user_uid;
+	state->euid = user_uid;
+	state->suid = ROOT_UID;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_USER: uid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->ruid, (int)ostate->euid, (int)ostate->suid,
+	    (int)state->ruid, (int)state->euid, (int)state->suid);
+	if (ostate->euid != ROOT_UID || ostate->suid != ROOT_UID) {
+	    if (setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, ROOT_UID)) {
+		snprintf(errbuf, sizeof(errbuf),
+		    "PERM_USER: setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, %d)",
+		    ROOT_UID);
+		goto bad;
+	    }
+	}
+	if (setuidx(ID_EFFECTIVE|ID_REAL, user_uid)) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_USER: setuidx(ID_EFFECTIVE|ID_REAL, %d)", user_uid);
+	    goto bad;
+	}
+	break;
+
+    case PERM_FULL_USER:
+	/* headed for exec() */
+	state->rgid = user_gid;
+	state->egid = user_gid;
+	state->sgid = user_gid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_FULL_USER: gid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->rgid, (int)ostate->egid, (int)ostate->sgid,
+	    (int)state->rgid, (int)state->egid, (int)state->sgid);
+	if (GID_CHANGED && setgidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, user_gid)) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_FULL_USER: setgidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, %d)",
+		user_gid);
+	    goto bad;
+	}
+	state->grlist = user_group_list;
+	sudo_grlist_addref(state->grlist);
+	if (state->grlist != ostate->grlist) {
+	    if (sudo_setgroups(state->grlist->ngids, state->grlist->gids)) {
+		errstr = "PERM_FULL_USER: setgroups";
+		goto bad;
+	    }
+	}
+	state->ruid = user_uid;
+	state->euid = user_uid;
+	state->suid = user_uid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_FULL_USER: uid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->ruid, (int)ostate->euid, (int)ostate->suid,
+	    (int)state->ruid, (int)state->euid, (int)state->suid);
+	if (UID_CHANGED && setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, user_uid)) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_FULL_USER: setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, %d)",
+		user_uid);
+	    goto bad;
+	}
+	break;
+
+    case PERM_RUNAS:
+	state->rgid = ostate->rgid;
+	state->egid = runas_gr ? runas_gr->gr_gid : runas_pw->pw_gid;
+	state->sgid = ostate->sgid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_RUNAS: gid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->rgid, (int)ostate->egid, (int)ostate->sgid,
+	    (int)state->rgid, (int)state->egid, (int)state->sgid);
+	if (GID_CHANGED && setgidx(ID_EFFECTIVE, state->egid)) {
+	    errstr = N_("unable to change to runas gid");
+	    goto bad;
+	}
+	state->grlist = runas_setgroups();
+	state->ruid = ostate->ruid;
+	state->euid = runas_pw ? runas_pw->pw_uid : user_uid;
+	state->suid = ostate->suid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_RUNAS: uid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->ruid, (int)ostate->euid, (int)ostate->suid,
+	    (int)state->ruid, (int)state->euid, (int)state->suid);
+	if (UID_CHANGED && setuidx(ID_EFFECTIVE, state->euid)) {
+	    errstr = N_("unable to change to runas uid");
+	    goto bad;
+	}
+	break;
+
+    case PERM_SUDOERS:
+	state->grlist = ostate->grlist;
+	sudo_grlist_addref(state->grlist);
+
+	/* assume euid == ROOT_UID, ruid == user */
+	state->rgid = ostate->rgid;
+	state->egid = sudoers_gid;
+	state->sgid = ostate->sgid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_SUDOERS: gid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->rgid, (int)ostate->egid, (int)ostate->sgid,
+	    (int)state->rgid, (int)state->egid, (int)state->sgid);
+	if (GID_CHANGED && setgidx(ID_EFFECTIVE, sudoers_gid)) {
+	    errstr = N_("unable to change to sudoers gid");
+	    goto bad;
+	}
+
+	state->ruid = ROOT_UID;
+	/*
+	 * If sudoers_uid == ROOT_UID and sudoers_mode is group readable
+	 * we use a non-zero uid in order to avoid NFS lossage.
+	 * Using uid 1 is a bit bogus but should work on all OS's.
+	 */
+	if (sudoers_uid == ROOT_UID && (sudoers_mode & S_IRGRP))
+	    state->euid = 1;
+	else
+	    state->euid = sudoers_uid;
+	state->suid = ROOT_UID;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_SUDOERS: uid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->ruid, (int)ostate->euid, (int)ostate->suid,
+	    (int)state->ruid, (int)state->euid, (int)state->suid);
+	if (UID_CHANGED) {
+	    if (ostate->ruid != ROOT_UID || ostate->suid != ROOT_UID) {
+		if (setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, ROOT_UID)) {
+		    snprintf(errbuf, sizeof(errbuf),
+			"PERM_SUDOERS: setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, %d)",
+			ROOT_UID);
+		    goto bad;
+		}
+	    }
+	    if (setuidx(ID_EFFECTIVE, state->euid)) {
+		snprintf(errbuf, sizeof(errbuf),
+		    "PERM_SUDOERS: setuidx(ID_EFFECTIVE, %d)", sudoers_uid);
+		goto bad;
+	    }
+	}
+	break;
+
+    case PERM_TIMESTAMP:
+	state->grlist = ostate->grlist;
+	sudo_grlist_addref(state->grlist);
+	state->rgid = ostate->rgid;
+	state->egid = ostate->egid;
+	state->sgid = ostate->sgid;
+	state->ruid = ROOT_UID;
+	state->euid = timestamp_uid;
+	state->suid = ROOT_UID;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_TIMESTAMP: uid: "
+	    "[%d, %d, %d] -> [%d, %d, %d]", __func__,
+	    (int)ostate->ruid, (int)ostate->euid, (int)ostate->suid,
+	    (int)state->ruid, (int)state->euid, (int)state->suid);
+	if (UID_CHANGED) {
+	    if (ostate->ruid != ROOT_UID || ostate->suid != ROOT_UID) {
+		if (setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, ROOT_UID)) {
+		    snprintf(errbuf, sizeof(errbuf),
+			"PERM_TIMESTAMP: setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, %d)",
+			ROOT_UID);
+		    goto bad;
+		}
+	    }
+	    if (setuidx(ID_EFFECTIVE, timestamp_uid)) {
+		snprintf(errbuf, sizeof(errbuf),
+		    "PERM_TIMESTAMP: setuidx(ID_EFFECTIVE, %d)", timestamp_uid);
+		goto bad;
+	    }
+	}
+	break;
+    }
+
+    perm_stack_depth++;
+    debug_return_bool(1);
+bad:
+    if (errno == EAGAIN)
+	warningx(U_("%s: %s"), U_(errstr), U_("too many processes"));
+    else
+	warning("%s", U_(errstr));
+    if (noexit)
+	debug_return_bool(0);
+    exit(1);
+}
+
+void
+restore_perms(void)
+{
+    struct perm_state *state, *ostate;
+    debug_decl(restore_perms, SUDO_DEBUG_PERMS)
+
+    if (perm_stack_depth < 2)
+	debug_return;
+
+    state = &perm_stack[perm_stack_depth - 1];
+    ostate = &perm_stack[perm_stack_depth - 2];
+    perm_stack_depth--;
+
+    sudo_debug_printf(SUDO_DEBUG_INFO, "%s: uid: [%d, %d, %d] -> [%d, %d, %d]",
+	__func__, (int)state->ruid, (int)state->euid, (int)state->suid,
+	(int)ostate->ruid, (int)ostate->euid, (int)ostate->suid);
+    sudo_debug_printf(SUDO_DEBUG_INFO, "%s: gid: [%d, %d, %d] -> [%d, %d, %d]",
+	__func__, (int)state->rgid, (int)state->egid, (int)state->sgid,
+	(int)ostate->rgid, (int)ostate->egid, (int)ostate->sgid);
+
+    if (OID(ruid) != -1 || OID(euid) != -1 || OID(suid) != -1) {
+	if (OID(euid) == ROOT_UID) {
+	    sudo_debug_printf(SUDO_DEBUG_INFO, "%s: setuidx(ID_EFFECTIVE, %d)",
+		__func__, ROOT_UID);
+	    if (setuidx(ID_EFFECTIVE, ROOT_UID)) {
+		warning("setuidx(ID_EFFECTIVE) [%d, %d, %d] -> [%d, %d, %d]",
+		    (int)state->ruid, (int)state->euid, (int)state->suid,
+		    -1, ROOT_UID, -1);
+		goto bad;
+	    }
+	}
+	if (OID(ruid) == OID(euid) && OID(euid) == OID(suid)) {
+	    sudo_debug_printf(SUDO_DEBUG_INFO,
+		"%s: setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, %d)",
+		__func__, OID(ruid));
+	    if (setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, OID(ruid))) {
+		warning("setuidx(ID_EFFECTIVE|ID_REAL|ID_SAVED) [%d, %d, %d] -> [%d, %d, %d]",
+		    (int)state->ruid, (int)state->euid, (int)state->suid,
+		    (int)OID(ruid), (int)OID(euid), (int)OID(suid));
+		goto bad;
+	    }
+	} else if (OID(ruid) == -1 && OID(suid) == -1) {
+	    /* May have already changed euid to ROOT_UID above. */
+	    if (OID(euid) != ROOT_UID) {
+		sudo_debug_printf(SUDO_DEBUG_INFO,
+		    "%s: setuidx(ID_EFFECTIVE, %d)", __func__, OID(euid));
+		if (setuidx(ID_EFFECTIVE, OID(euid))) {
+		    warning("setuidx(ID_EFFECTIVE) [%d, %d, %d] -> [%d, %d, %d]",
+			(int)state->ruid, (int)state->euid, (int)state->suid,
+			(int)OID(ruid), (int)OID(euid), (int)OID(suid));
+		    goto bad;
+		}
+	    }
+	} else if (OID(suid) == -1) {
+	    /* Cannot set the real uid alone. */
+	    sudo_debug_printf(SUDO_DEBUG_INFO,
+		"%s: setuidx(ID_REAL|ID_EFFECTIVE, %d)", __func__, OID(ruid));
+	    if (setuidx(ID_REAL|ID_EFFECTIVE, OID(ruid))) {
+		warning("setuidx(ID_REAL|ID_EFFECTIVE) [%d, %d, %d] -> [%d, %d, %d]",
+		    (int)state->ruid, (int)state->euid, (int)state->suid,
+		    (int)OID(ruid), (int)OID(euid), (int)OID(suid));
+		goto bad;
+	    }
+	    /* Restore the effective euid if it doesn't match the ruid. */
+	    if (OID(euid) != OID(ruid)) {
+		sudo_debug_printf(SUDO_DEBUG_INFO,
+		    "%s: setuidx(ID_EFFECTIVE, %d)", __func__, ostate->euid);
+		if (setuidx(ID_EFFECTIVE, ostate->euid)) {
+		    warning("setuidx(ID_EFFECTIVE, %d)", ostate->euid);
+		    goto bad;
+		}
+	    }
+	}
+    }
+    if (OID(rgid) != -1 || OID(egid) != -1 || OID(sgid) != -1) {
+	if (OID(rgid) == OID(egid) && OID(egid) == OID(sgid)) {
+	    sudo_debug_printf(SUDO_DEBUG_INFO,
+		"%s: setgidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, %d)",
+		__func__, OID(rgid));
+	    if (setgidx(ID_EFFECTIVE|ID_REAL|ID_SAVED, OID(rgid))) {
+		warning("setgidx(ID_EFFECTIVE|ID_REAL|ID_SAVED) [%d, %d, %d] -> [%d, %d, %d]",
+		    (int)state->rgid, (int)state->egid, (int)state->sgid,
+		    (int)OID(rgid), (int)OID(egid), (int)OID(sgid));
+		goto bad;
+	    }
+	} else if (OID(rgid) == -1 && OID(sgid) == -1) {
+	    sudo_debug_printf(SUDO_DEBUG_INFO, "%s: setgidx(ID_EFFECTIVE, %d)",
+		__func__, OID(egid));
+	    if (setgidx(ID_EFFECTIVE, OID(egid))) {
+		warning("setgidx(ID_EFFECTIVE) [%d, %d, %d] -> [%d, %d, %d]",
+		    (int)state->rgid, (int)state->egid, (int)state->sgid,
+		    (int)OID(rgid), (int)OID(egid), (int)OID(sgid));
+		goto bad;
+	    }
+	} else if (OID(sgid) == -1) {
+	    sudo_debug_printf(SUDO_DEBUG_INFO,
+		"%s: setgidx(ID_EFFECTIVE|ID_REAL, %d)", __func__, OID(rgid));
+	    if (setgidx(ID_REAL|ID_EFFECTIVE, OID(rgid))) {
+		warning("setgidx(ID_REAL|ID_EFFECTIVE) [%d, %d, %d] -> [%d, %d, %d]",
+		    (int)state->rgid, (int)state->egid, (int)state->sgid,
+		    (int)OID(rgid), (int)OID(egid), (int)OID(sgid));
+		goto bad;
+	    }
+	}
+    }
+    if (state->grlist != ostate->grlist) {
+	if (sudo_setgroups(ostate->grlist->ngids, ostate->grlist->gids)) {
+	    warning("setgroups()");
+	    goto bad;
+	}
+    }
+    sudo_grlist_delref(state->grlist);
+    debug_return;
+
+bad:
+    exit(1);
+}
+
+#elif defined(HAVE_SETREUID)
+
+#define UID_CHANGED (state->ruid != ostate->ruid || state->euid != ostate->euid)
+#define GID_CHANGED (state->rgid != ostate->rgid || state->egid != ostate->egid)
+
+/*
+ * Set real and effective and saved uids and gids based on perm.
+ * We always retain a saved uid of 0 unless we are headed for an exec().
+ * We only flip the effective gid since it only changes for PERM_SUDOERS.
+ * This version of set_perms() works fine with the "stay_setuid" option.
+ */
+int
+set_perms(int perm)
+{
+    struct perm_state *state, *ostate = NULL;
+    char errbuf[1024];
+    const char *errstr = errbuf;
+    int noexit;
+    debug_decl(set_perms, SUDO_DEBUG_PERMS)
+
+    noexit = ISSET(perm, PERM_NOEXIT);
+    CLR(perm, PERM_MASK);
+
+    if (perm_stack_depth == PERM_STACK_MAX) {
+	errstr = N_("perm stack overflow");
+	errno = EINVAL;
+	goto bad;
+    }
+
+    state = &perm_stack[perm_stack_depth];
+    if (perm != PERM_INITIAL) {
+	if (perm_stack_depth == 0) {
+	    errstr = N_("perm stack underflow");
+	    errno = EINVAL;
+	    goto bad;
+	}
+	ostate = &perm_stack[perm_stack_depth - 1];
+    }
+
+    switch (perm) {
+    case PERM_INITIAL:
+	/* Stash initial state */
 	state->ruid = getuid();
 	state->euid = geteuid();
 	state->rgid = getgid();
 	state->egid = getegid();
 	state->grlist = user_group_list;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_INITIAL: "
+	    "ruid: %d, euid: %d, rgid: %d, egid: %d", __func__,
+	    (int)state->ruid, (int)state->euid,
+	    (int)state->rgid, (int)state->egid);
 	break;
 
     case PERM_ROOT:
+	state->ruid = ROOT_UID;
+	state->euid = ROOT_UID;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_ROOT: uid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->ruid,
+	    (int)ostate->euid, (int)state->ruid, (int)state->euid);
 	/*
-	 * setreuid(0, 0) may fail on some systems
-	 * when the euid is not already 0.
+	 * setreuid(0, 0) may fail on some systems if euid is not already 0.
 	 */
-	if (setreuid(-1, ROOT_UID)) {
-	    errstr = "setreuid(-1, ROOT_UID)";
-	    goto bad;
+	if (ostate->euid != ROOT_UID) {
+	    if (setreuid(-1, ROOT_UID)) {
+		snprintf(errbuf, sizeof(errbuf),
+		    "PERM_ROOT: setreuid(-1, %d)", ROOT_UID);
+		goto bad;
+	    }
 	}
-	if (setuid(ROOT_UID)) {
-	    errstr = "setuid(ROOT_UID)";
+	if (ostate->ruid != ROOT_UID) {
+	    if (setreuid(ROOT_UID, -1)) {
+		snprintf(errbuf, sizeof(errbuf),
+		    "PERM_ROOT: setreuid(%d, -1)", ROOT_UID);
+		goto bad;
+	    }
+	}
+	state->rgid = ostate->rgid;
+	state->egid = ROOT_GID;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_ROOT: gid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->rgid,
+	    (int)ostate->egid, (int)state->rgid, (int)state->egid);
+	if (GID_CHANGED && setregid(ID(rgid), ID(egid))) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_ROOT: setregid(%d, %d)", ID(rgid), ID(egid));
 	    goto bad;
 	}
-	state->ruid = ROOT_UID;
-	state->euid = ROOT_UID;
-	state->rgid = -1;
-	state->egid = -1;
 	state->grlist = ostate->grlist;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 	break;
 
     case PERM_USER:
-	state->rgid = -1;
+	state->rgid = ostate->rgid;
 	state->egid = user_gid;
-	if (setregid(-1, ID(egid))) {
-	    errstr = "setregid(-1, user_gid)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_USER: gid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->rgid,
+	    (int)ostate->egid, (int)state->rgid, (int)state->egid);
+	if (GID_CHANGED && setregid(ID(rgid), ID(egid))) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_USER: setregid(%d, %d)", ID(rgid), ID(egid));
 	    goto bad;
 	}
 	state->grlist = user_group_list;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 	if (state->grlist != ostate->grlist) {
 	    if (sudo_setgroups(state->grlist->ngids, state->grlist->gids)) {
-		errstr = "setgroups()";
+		errstr = "PERM_USER: setgroups";
 		goto bad;
 	    }
 	}
 	state->ruid = ROOT_UID;
 	state->euid = user_uid;
-	if (setreuid(ID(ruid), ID(euid))) {
-	    errstr = "setreuid(ROOT_UID, user_uid)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_USER: uid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->ruid,
+	    (int)ostate->euid, (int)state->ruid, (int)state->euid);
+	if (UID_CHANGED && setreuid(ID(ruid), ID(euid))) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_USER: setreuid(%d, %d)", ID(ruid), ID(euid));
 	    goto bad;
 	}
 	break;
@@ -431,51 +951,70 @@ set_perms(int perm)
 	/* headed for exec() */
 	state->rgid = user_gid;
 	state->egid = user_gid;
-	if (setregid(ID(rgid), ID(egid))) {
-	    errstr = "setregid(user_gid, user_gid)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_FULL_USER: gid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->rgid,
+	    (int)ostate->egid, (int)state->rgid, (int)state->egid);
+	if (GID_CHANGED && setregid(ID(rgid), ID(egid))) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_FULL_USER: setregid(%d, %d)", ID(rgid), ID(egid));
 	    goto bad;
 	}
 	state->grlist = user_group_list;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 	if (state->grlist != ostate->grlist) {
 	    if (sudo_setgroups(state->grlist->ngids, state->grlist->gids)) {
-		errstr = "setgroups()";
+		errstr = "PERM_FULL_USER: setgroups";
 		goto bad;
 	    }
 	}
 	state->ruid = user_uid;
 	state->euid = user_uid;
-	if (setreuid(ID(ruid), ID(euid))) {
-	    errstr = "setreuid(user_uid, user_uid)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_FULL_USER: uid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->ruid,
+	    (int)ostate->euid, (int)state->ruid, (int)state->euid);
+	if (UID_CHANGED && setreuid(ID(ruid), ID(euid))) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_FULL_USER: setreuid(%d, %d)", ID(ruid), ID(euid));
 	    goto bad;
 	}
 	break;
 
     case PERM_RUNAS:
-	state->rgid = -1;
+	state->rgid = ostate->rgid;
 	state->egid = runas_gr ? runas_gr->gr_gid : runas_pw->pw_gid;
-	if (setregid(ID(rgid), ID(egid))) {
-	    errstr = _("unable to change to runas gid");
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_RUNAS: gid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->rgid,
+	    (int)ostate->egid, (int)state->rgid, (int)state->egid);
+	if (GID_CHANGED && setregid(ID(rgid), ID(egid))) {
+	    errstr = N_("unable to change to runas gid");
 	    goto bad;
 	}
 	state->grlist = runas_setgroups();
 	state->ruid = ROOT_UID;
 	state->euid = runas_pw ? runas_pw->pw_uid : user_uid;
-	if (setreuid(ID(ruid), ID(euid))) {
-	    errstr = _("unable to change to runas uid");
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_RUNAS: uid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->ruid,
+	    (int)ostate->euid, (int)state->ruid, (int)state->euid);
+	if (UID_CHANGED && setreuid(ID(ruid), ID(euid))) {
+	    errstr = N_("unable to change to runas uid");
 	    goto bad;
 	}
 	break;
 
     case PERM_SUDOERS:
 	state->grlist = ostate->grlist;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 
 	/* assume euid == ROOT_UID, ruid == user */
-	state->rgid = -1;
+	state->rgid = ostate->rgid;
 	state->egid = sudoers_gid;
-	if (setregid(-1, ID(egid)))
-	    error(1, _("unable to change to sudoers gid"));
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_SUDOERS: gid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->rgid,
+	    (int)ostate->egid, (int)state->rgid, (int)state->egid);
+	if (GID_CHANGED && setregid(ID(rgid), ID(egid))) {
+	    errstr = N_("unable to change to sudoers gid");
+	    goto bad;
+	}
 
 	state->ruid = ROOT_UID;
 	/*
@@ -483,39 +1022,47 @@ set_perms(int perm)
 	 * we use a non-zero uid in order to avoid NFS lossage.
 	 * Using uid 1 is a bit bogus but should work on all OS's.
 	 */
-	if (sudoers_uid == ROOT_UID && (sudoers_mode & 040))
+	if (sudoers_uid == ROOT_UID && (sudoers_mode & S_IRGRP))
 	    state->euid = 1;
 	else
 	    state->euid = sudoers_uid;
-	if (setreuid(ID(ruid), ID(euid))) {
-	    errstr = "setreuid(ROOT_UID, SUDOERS_UID)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_SUDOERS: uid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->ruid,
+	    (int)ostate->euid, (int)state->ruid, (int)state->euid);
+	if (UID_CHANGED && setreuid(ID(ruid), ID(euid))) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_SUDOERS: setreuid(%d, %d)", ID(ruid), ID(euid));
 	    goto bad;
 	}
 	break;
 
     case PERM_TIMESTAMP:
 	state->grlist = ostate->grlist;
-	grlist_addref(state->grlist);
-	state->rgid = -1;
-	state->egid = -1;
+	sudo_grlist_addref(state->grlist);
+	state->rgid = ostate->rgid;
+	state->egid = ostate->egid;
 	state->ruid = ROOT_UID;
 	state->euid = timestamp_uid;
-	if (setreuid(ID(ruid), ID(euid))) {
-	    errstr = "setreuid(ROOT_UID, timestamp_uid)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_TIMESTAMP: uid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->ruid,
+	    (int)ostate->euid, (int)state->ruid, (int)state->euid);
+	if (UID_CHANGED && setreuid(ID(ruid), ID(euid))) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_TIMESTAMP: setreuid(%d, %d)", ID(ruid), ID(euid));
 	    goto bad;
 	}
 	break;
     }
 
-done:
     perm_stack_depth++;
-    return 1;
+    debug_return_bool(1);
 bad:
-    /* XXX - better warnings inline */
-    warningx("%s: %s", errstr,
-	errno == EAGAIN ? _("too many processes") : strerror(errno));
+    if (errno == EAGAIN)
+	warningx(U_("%s: %s"), U_(errstr), U_("too many processes"));
+    else
+	warning("%s", U_(errstr));
     if (noexit)
-	return 0;
+	debug_return_bool(0);
     exit(1);
 }
 
@@ -523,14 +1070,22 @@ void
 restore_perms(void)
 {
     struct perm_state *state, *ostate;
+    debug_decl(restore_perms, SUDO_DEBUG_PERMS)
 
     if (perm_stack_depth < 2)
-	return;
+	debug_return;
 
     state = &perm_stack[perm_stack_depth - 1];
     ostate = &perm_stack[perm_stack_depth - 2];
     perm_stack_depth--;
 
+    sudo_debug_printf(SUDO_DEBUG_INFO, "%s: uid: [%d, %d] -> [%d, %d]",
+	__func__, (int)state->ruid, (int)state->euid,
+	(int)ostate->ruid, (int)ostate->euid);
+    sudo_debug_printf(SUDO_DEBUG_INFO, "%s: gid: [%d, %d] -> [%d, %d]",
+	__func__, (int)state->rgid, (int)state->egid,
+	(int)ostate->rgid, (int)ostate->egid);
+
     /*
      * When changing euid to ROOT_UID, setreuid() may fail even if
      * the ruid is ROOT_UID so call setuid() first.
@@ -538,7 +1093,7 @@ restore_perms(void)
     if (OID(euid) == ROOT_UID) {
 	/* setuid() may not set the saved ID unless the euid is ROOT_UID */
 	if (ID(euid) != ROOT_UID)
-	    (void)setreuid(-1, ROOT_UID);
+	    ignore_result(setreuid(-1, ROOT_UID));
 	if (setuid(ROOT_UID)) {
 	    warning("setuid() [%d, %d] -> %d)", (int)state->ruid,
 		(int)state->euid, ROOT_UID);
@@ -561,16 +1116,17 @@ restore_perms(void)
 	    goto bad;
 	}
     }
-    grlist_delref(state->grlist);
-    return;
+    sudo_grlist_delref(state->grlist);
+    debug_return;
 
 bad:
     exit(1);
 }
 
-# else /* !HAVE_SETRESUID && !HAVE_SETREUID */
-# ifdef HAVE_SETEUID
+#elif defined(HAVE_SETEUID)
 
+#define GID_CHANGED (state->rgid != ostate->rgid || state->egid != ostate->egid)
+
 /*
  * Set real and effective uids and gids based on perm.
  * We always retain a real or effective uid of ROOT_UID unless
@@ -581,14 +1137,16 @@ int
 set_perms(int perm)
 {
     struct perm_state *state, *ostate = NULL;
-    const char *errstr;
+    char errbuf[1024];
+    const char *errstr = errbuf;
     int noexit;
+    debug_decl(set_perms, SUDO_DEBUG_PERMS)
 
     noexit = ISSET(perm, PERM_NOEXIT);
     CLR(perm, PERM_MASK);
 
     if (perm_stack_depth == PERM_STACK_MAX) {
-	errstr = _("perm stack overflow");
+	errstr = N_("perm stack overflow");
 	errno = EINVAL;
 	goto bad;
     }
@@ -596,13 +1154,11 @@ set_perms(int perm)
     state = &perm_stack[perm_stack_depth];
     if (perm != PERM_INITIAL) {
 	if (perm_stack_depth == 0) {
-	    errstr = _("perm stack underflow");
+	    errstr = N_("perm stack underflow");
 	    errno = EINVAL;
 	    goto bad;
 	}
 	ostate = &perm_stack[perm_stack_depth - 1];
-	if (memcmp(state, ostate, sizeof(*state)) == 0)
-	    goto done;
     }
 
     /*
@@ -611,12 +1167,12 @@ set_perms(int perm)
      * real and effective uids to ROOT_UID initially to be safe.
      */
     if (perm != PERM_INITIAL) {
-	if (seteuid(ROOT_UID)) {
-	    errstr = "seteuid(ROOT_UID)";
+	if (ostate->euid != ROOT_UID && seteuid(ROOT_UID)) {
+	    snprintf(errbuf, sizeof(errbuf), "set_perms: seteuid(%d)", ROOT_UID);
 	    goto bad;
 	}
-	if (setuid(ROOT_UID)) {
-	    errstr = "setuid(ROOT_UID)";
+	if (ostate->ruid != ROOT_UID && setuid(ROOT_UID)) {
+	    snprintf(errbuf, sizeof(errbuf), "set_perms: setuid(%d)", ROOT_UID);
 	    goto bad;
 	}
     }
@@ -629,38 +1185,60 @@ set_perms(int perm)
 	state->rgid = getgid();
 	state->egid = getegid();
 	state->grlist = user_group_list;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_INITIAL: "
+	    "ruid: %d, euid: %d, rgid: %d, egid: %d", __func__,
+	    (int)state->ruid, (int)state->euid,
+	    (int)state->rgid, (int)state->egid);
 	break;
 
     case PERM_ROOT:
 	/* We already set ruid/euid above. */
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_ROOT: uid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->ruid,
+	    (int)ostate->euid, ROOT_UID, ROOT_UID);
 	state->ruid = ROOT_UID;
 	state->euid = ROOT_UID;
-	state->rgid = -1;
-	state->egid = -1;
+	state->rgid = ostate->rgid;
+	state->egid = ROOT_GID;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_ROOT: gid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->rgid,
+	    (int)ostate->egid, ROOT_GID, ROOT_GID);
+	if (GID_CHANGED && setegid(ROOT_GID)) {
+	    errstr = N_("unable to change to root gid");
+	    goto bad;
+	}
 	state->grlist = ostate->grlist;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 	break;
 
     case PERM_USER:
 	state->egid = user_gid;
-	if (setegid(ID(egid))) {
-	    errstr = "setegid(user_gid)";
+	state->rgid = ostate->rgid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_USER: gid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->rgid,
+	    (int)ostate->egid, (int)state->rgid, (int)state->egid);
+	if (GID_CHANGED && setegid(user_gid)) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_USER: setegid(%d)", user_gid);
 	    goto bad;
 	}
 	state->grlist = user_group_list;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 	if (state->grlist != ostate->grlist) {
 	    if (sudo_setgroups(state->grlist->ngids, state->grlist->gids)) {
-		errstr = "setgroups()";
+		errstr = "PERM_USER: setgroups";
 		goto bad;
 	    }
 	}
-	state->rgid = -1;
 	state->ruid = ROOT_UID;
 	state->euid = user_uid;
-	if (seteuid(ID(euid))) {
-	    errstr = "seteuid(user_uid)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_USER: uid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->ruid,
+	    (int)ostate->euid, (int)state->ruid, (int)state->euid);
+	if (seteuid(user_uid)) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_USER: seteuid(%d)", user_uid);
 	    goto bad;
 	}
 	break;
@@ -669,51 +1247,70 @@ set_perms(int perm)
 	/* headed for exec() */
 	state->rgid = user_gid;
 	state->egid = user_gid;
-	if (setgid(user_gid)) {
-	    errstr = "setgid(user_gid)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_FULL_USER: gid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->rgid,
+	    (int)ostate->egid, (int)state->rgid, (int)state->egid);
+	if (GID_CHANGED && setgid(user_gid)) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_FULL_USER: setgid(%d)", user_gid);
 	    goto bad;
 	}
 	state->grlist = user_group_list;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 	if (state->grlist != ostate->grlist) {
 	    if (sudo_setgroups(state->grlist->ngids, state->grlist->gids)) {
-		errstr = "setgroups()";
+		errstr = "PERM_FULL_USER: setgroups";
 		goto bad;
 	    }
 	}
 	state->ruid = user_uid;
 	state->euid = user_uid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_FULL_USER: uid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->ruid,
+	    (int)ostate->euid, (int)state->ruid, (int)state->euid);
 	if (setuid(user_uid)) {
-	    errstr = "setuid(user_uid)";
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_FULL_USER: setuid(%d)", user_uid);
 	    goto bad;
 	}
 	break;
 
     case PERM_RUNAS:
-	state->rgid = -1;
+	state->rgid = ostate->rgid;
 	state->egid = runas_gr ? runas_gr->gr_gid : runas_pw->pw_gid;
-	if (setegid(ID(egid))) {
-	    errstr = _("unable to change to runas gid");
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_RUNAS: gid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->rgid,
+	    (int)ostate->egid, (int)state->rgid, (int)state->egid);
+	if (GID_CHANGED && setegid(state->egid)) {
+	    errstr = N_("unable to change to runas gid");
 	    goto bad;
 	}
 	state->grlist = runas_setgroups();
-	state->ruid = -1;
+	state->ruid = ostate->ruid;
 	state->euid = runas_pw ? runas_pw->pw_uid : user_uid;
-	if (seteuid(ID(euid))) {
-	    errstr = _("unable to change to runas uid");
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_RUNAS: uid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->ruid,
+	    (int)ostate->euid, (int)state->ruid, (int)state->euid);
+	if (seteuid(state->euid)) {
+	    errstr = N_("unable to change to runas uid");
 	    goto bad;
 	}
 	break;
 
     case PERM_SUDOERS:
 	state->grlist = ostate->grlist;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 
 	/* assume euid == ROOT_UID, ruid == user */
-	state->rgid = -1;
+	state->rgid = ostate->rgid;
 	state->egid = sudoers_gid;
-	if (setegid(ID(egid)))
-	    error(1, _("unable to change to sudoers gid"));
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_SUDOERS: gid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->rgid,
+	    (int)ostate->egid, (int)state->rgid, (int)state->egid);
+	if (GID_CHANGED && setegid(sudoers_gid)) {
+	    errstr = N_("unable to change to sudoers gid");
+	    goto bad;
+	}
 
 	state->ruid = ROOT_UID;
 	/*
@@ -721,39 +1318,47 @@ set_perms(int perm)
 	 * we use a non-zero uid in order to avoid NFS lossage.
 	 * Using uid 1 is a bit bogus but should work on all OS's.
 	 */
-	if (sudoers_uid == ROOT_UID && (sudoers_mode & 040))
+	if (sudoers_uid == ROOT_UID && (sudoers_mode & S_IRGRP))
 	    state->euid = 1;
 	else
 	    state->euid = sudoers_uid;
-	if (seteuid(ID(euid))) {
-	    errstr = "seteuid(SUDOERS_UID)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_SUDOERS: uid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->ruid,
+	    (int)ostate->euid, (int)state->ruid, (int)state->euid);
+	if (seteuid(state->euid)) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_SUDOERS: seteuid(%d)", state->euid);
 	    goto bad;
 	}
 	break;
 
     case PERM_TIMESTAMP:
 	state->grlist = ostate->grlist;
-	grlist_addref(state->grlist);
-	state->rgid = -1;
-	state->egid = -1;
+	sudo_grlist_addref(state->grlist);
+	state->rgid = ostate->rgid;
+	state->egid = ostate->egid;
 	state->ruid = ROOT_UID;
 	state->euid = timestamp_uid;
-	if (seteuid(ID(euid))) {
-	    errstr = "seteuid(timestamp_uid)";
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_TIMESTAMP: uid: "
+	    "[%d, %d] -> [%d, %d]", __func__, (int)ostate->ruid,
+	    (int)ostate->euid, (int)state->ruid, (int)state->euid);
+	if (seteuid(timestamp_uid)) {
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_TIMESTAMP: seteuid(%d)", timestamp_uid);
 	    goto bad;
 	}
 	break;
     }
 
-done:
     perm_stack_depth++;
-    return 1;
+    debug_return_bool(1);
 bad:
-    /* XXX - better warnings inline */
-    warningx("%s: %s", errstr,
-	errno == EAGAIN ? _("too many processes") : strerror(errno));
+    if (errno == EAGAIN)
+	warningx(U_("%s: %s"), U_(errstr), U_("too many processes"));
+    else
+	warning("%s", U_(errstr));
     if (noexit)
-	return 0;
+	debug_return_bool(0);
     exit(1);
 }
 
@@ -761,30 +1366,39 @@ void
 restore_perms(void)
 {
     struct perm_state *state, *ostate;
+    debug_decl(restore_perms, SUDO_DEBUG_PERMS)
 
     if (perm_stack_depth < 2)
-	return;
+	debug_return;
 
     state = &perm_stack[perm_stack_depth - 1];
     ostate = &perm_stack[perm_stack_depth - 2];
     perm_stack_depth--;
 
+    sudo_debug_printf(SUDO_DEBUG_INFO, "%s: uid: [%d, %d] -> [%d, %d]",
+	__func__, (int)state->ruid, (int)state->euid,
+	(int)ostate->ruid, (int)ostate->euid);
+    sudo_debug_printf(SUDO_DEBUG_INFO, "%s: gid: [%d, %d] -> [%d, %d]",
+	__func__, (int)state->rgid, (int)state->egid,
+	(int)ostate->rgid, (int)ostate->egid);
+
     /*
      * Since we only have setuid() and seteuid() and semantics
      * for these calls differ on various systems, we set
      * real and effective uids to ROOT_UID initially to be safe.
      */
     if (seteuid(ROOT_UID)) {
-	errstr = "seteuid(ROOT_UID)";
+	warningx("seteuid() [%d] -> [%d]", (int)state->euid, ROOT_UID);
 	goto bad;
     }
     if (setuid(ROOT_UID)) {
-	errstr = "setuid(ROOT_UID)";
+	warningx("setuid() [%d, %d] -> [%d, %d]", (int)state->ruid, ROOT_UID,
+	    ROOT_UID, ROOT_UID);
 	goto bad;
     }
 
-    if (setegid(OID(egid))) {
-	warning("setegid(%d)", (int)OID(egid));
+    if (OID(egid) != -1 && setegid(ostate->egid)) {
+	warning("setegid(%d)", (int)ostate->egid);
 	goto bad;
     }
     if (state->grlist != ostate->grlist) {
@@ -793,18 +1407,18 @@ restore_perms(void)
 	    goto bad;
 	}
     }
-    if (seteuid(OID(euid))) {
-	warning("seteuid(%d)", (int)OID(euid));
+    if (OID(euid) != -1 && seteuid(ostate->euid)) {
+	warning("seteuid(%d)", ostate->euid);
 	goto bad;
     }
-    grlist_delref(state->grlist);
-    return;
+    sudo_grlist_delref(state->grlist);
+    debug_return;
 
 bad:
     exit(1);
 }
 
-# else /* !HAVE_SETRESUID && !HAVE_SETREUID && !HAVE_SETEUID */
+#else /* !HAVE_SETRESUID && !HAVE_SETREUID && !HAVE_SETEUID */
 
 /*
  * Set uids and gids based on perm via setuid() and setgid().
@@ -815,14 +1429,16 @@ int
 set_perms(int perm)
 {
     struct perm_state *state, *ostate = NULL;
-    const char *errstr;
+    char errbuf[1024];
+    const char *errstr = errbuf;
     int noexit;
+    debug_decl(set_perms, SUDO_DEBUG_PERMS)
 
     noexit = ISSET(perm, PERM_NOEXIT);
     CLR(perm, PERM_MASK);
 
     if (perm_stack_depth == PERM_STACK_MAX) {
-	errstr = _("perm stack overflow");
+	errstr = N_("perm stack overflow");
 	errno = EINVAL;
 	goto bad;
     }
@@ -830,49 +1446,62 @@ set_perms(int perm)
     state = &perm_stack[perm_stack_depth];
     if (perm != PERM_INITIAL) {
 	if (perm_stack_depth == 0) {
-	    errstr = _("perm stack underflow");
+	    errstr = N_("perm stack underflow");
 	    errno = EINVAL;
 	    goto bad;
 	}
 	ostate = &perm_stack[perm_stack_depth - 1];
-	if (memcmp(state, ostate, sizeof(*state)) == 0)
-	    goto done;
     }
 
     switch (perm) {
     case PERM_INITIAL:
 	/* Stash initial state */
-	state->ruid = getuid();
+	state->ruid = geteuid() == ROOT_UID ? ROOT_UID : getuid();
 	state->rgid = getgid();
 	state->grlist = user_group_list;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_INITIAL: "
+	    "ruid: %d, rgid: %d", __func__, (int)state->ruid, (int)state->rgid);
 	break;
 
     case PERM_ROOT:
 	state->ruid = ROOT_UID;
-	state->rgid = -1;
+	state->rgid = ROOT_GID;
 	state->grlist = ostate->grlist;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_ROOT: uid: "
+	    "[%d] -> [%d]", __func__, (int)ostate->ruid, (int)state->ruid);
 	if (setuid(ROOT_UID)) {
-	    errstr = "setuid(ROOT_UID)";
+	    snprintf(errbuf, sizeof(errbuf), "PERM_ROOT: setuid(%d)", ROOT_UID);
 	    goto bad;
 	}
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_ROOT: gid: "
+	    "[%d] -> [%d]", __func__, (int)ostate->rgid, (int)state->rgid);
+	if (setgid(ROOT_GID)) {
+	    errstr = N_("unable to change to root gid");
+	    goto bad;
+	}
 	break;
 
     case PERM_FULL_USER:
 	state->rgid = user_gid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_FULL_USER: gid: "
+	    "[%d] -> [%d]", __func__, (int)ostate->rgid, (int)state->rgid);
 	(void) setgid(user_gid);
 	state->grlist = user_group_list;
-	grlist_addref(state->grlist);
+	sudo_grlist_addref(state->grlist);
 	if (state->grlist != ostate->grlist) {
 	    if (sudo_setgroups(state->grlist->ngids, state->grlist->gids)) {
-		errstr = "setgroups()";
+		errstr = "PERM_FULL_USER: setgroups";
 		goto bad;
 	    }
 	}
 	state->ruid = user_uid;
+	sudo_debug_printf(SUDO_DEBUG_INFO, "%s: PERM_FULL_USER: uid: "
+	    "[%d] -> [%d]", __func__, (int)ostate->ruid, (int)state->ruid);
 	if (setuid(user_uid)) {
-	    errstr = "setuid(user_uid)";
+	    snprintf(errbuf, sizeof(errbuf),
+		"PERM_FULL_USER: setuid(%d)", user_uid);
 	    goto bad;
 	}
 	break;
@@ -882,18 +1511,22 @@ set_perms(int perm)
     case PERM_RUNAS:
     case PERM_TIMESTAMP:
 	/* Unsupported since we can't set euid. */
+	state->ruid = ostate->ruid;
+	state->rgid = ostate->rgid;
+	state->grlist = ostate->grlist;
+	sudo_grlist_addref(state->grlist);
 	break;
     }
 
-done:
     perm_stack_depth++;
-    return 1;
+    debug_return_bool(1);
 bad:
-    /* XXX - better warnings inline */
-    warningx("%s: %s", errstr,
-	errno == EAGAIN ? _("too many processes") : strerror(errno));
+    if (errno == EAGAIN)
+	warningx(U_("%s: %s"), U_(errstr), U_("too many processes"));
+    else
+	warning("%s", U_(errstr));
     if (noexit)
-	return 0;
+	debug_return_bool(0);
     exit(1);
 }
 
@@ -901,14 +1534,20 @@ void
 restore_perms(void)
 {
     struct perm_state *state, *ostate;
+    debug_decl(restore_perms, SUDO_DEBUG_PERMS)
 
     if (perm_stack_depth < 2)
-	return;
+	debug_return;
 
     state = &perm_stack[perm_stack_depth - 1];
     ostate = &perm_stack[perm_stack_depth - 2];
     perm_stack_depth--;
 
+    sudo_debug_printf(SUDO_DEBUG_INFO, "%s: uid: [%d] -> [%d]",
+	__func__, (int)state->ruid, (int)ostate->ruid);
+    sudo_debug_printf(SUDO_DEBUG_INFO, "%s: gid: [%d] -> [%d]",
+	__func__, (int)state->rgid, (int)ostate->rgid);
+
     if (OID(rgid) != -1 && setgid(ostate->rgid)) {
 	warning("setgid(%d)", (int)ostate->rgid);
 	goto bad;
@@ -919,40 +1558,41 @@ restore_perms(void)
 	    goto bad;
 	}
     }
-    grlist_delref(state->grlist);
+    sudo_grlist_delref(state->grlist);
     if (OID(ruid) != -1 && setuid(ostate->ruid)) {
 	warning("setuid(%d)", (int)ostate->ruid);
 	goto bad;
     }
-    return;
+    debug_return;
 
 bad:
     exit(1);
 }
-#  endif /* HAVE_SETEUID */
-# endif /* HAVE_SETREUID */
-#endif /* HAVE_SETRESUID */
+#endif /* HAVE_SETRESUID || HAVE_SETREUID || HAVE_SETEUID */
 
+#if defined(HAVE_SETRESUID) || defined(HAVE_SETREUID) || defined(HAVE_SETEUID)
 static struct group_list *
 runas_setgroups(void)
 {
     struct passwd *pw;
     struct group_list *grlist;
+    debug_decl(runas_setgroups, SUDO_DEBUG_PERMS)
 
     if (def_preserve_groups) {
-	grlist_addref(user_group_list);
-	return user_group_list;
+	sudo_grlist_addref(user_group_list);
+	debug_return_ptr(user_group_list);
     }
 
     pw = runas_pw ? runas_pw : sudo_user.pw;
 #ifdef HAVE_SETAUTHDB
     aix_setauthdb(pw->pw_name);
 #endif
-    grlist = get_group_list(pw);
+    grlist = sudo_get_grlist(pw);
 #ifdef HAVE_SETAUTHDB
     aix_restoreauthdb();
 #endif
     if (sudo_setgroups(grlist->ngids, grlist->gids) < 0)
-	log_error(USE_ERRNO|MSG_ONLY, _("unable to set runas group vector"));
-    return grlist;
+	log_fatal(USE_ERRNO|MSG_ONLY, N_("unable to set runas group vector"));
+    debug_return_ptr(grlist);
 }
+#endif /* HAVE_SETRESUID || HAVE_SETREUID || HAVE_SETEUID */