vendor/openssh/7.8p1

1 files changed, 6 insertions, 33 deletions

diff --git a/uidswap.c b/uidswap.c
index 8bf6b244e5c79..49f76d818a81d 100644
--- a/uidswap.c
+++ b/uidswap.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: uidswap.c,v 1.39 2015/06/24 01:49:19 dtucker Exp $ */
+/* $OpenBSD: uidswap.c,v 1.41 2018/07/18 11:34:04 dtucker Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -49,6 +49,7 @@ static gid_t	saved_egid = 0;
 /* Saved effective uid. */
 static int	privileged = 0;
 static int	temporarily_use_uid_effective = 0;
+static uid_t	user_groups_uid;
 static gid_t	*saved_egroups = NULL, *user_groups = NULL;
 static int	saved_egroupslen = -1, user_groupslen = -1;
 
@@ -92,10 +93,11 @@ temporarily_use_uid(struct passwd *pw)
 			fatal("getgroups: %.100s", strerror(errno));
 	} else { /* saved_egroupslen == 0 */
 		free(saved_egroups);
+		saved_egroups = NULL;
 	}
 
 	/* set and save the user's groups */
-	if (user_groupslen == -1) {
+	if (user_groupslen == -1 || user_groups_uid != pw->pw_uid) {
 		if (initgroups(pw->pw_name, pw->pw_gid) < 0)
 			fatal("initgroups: %s: %.100s", pw->pw_name,
 			    strerror(errno));
@@ -110,7 +112,9 @@ temporarily_use_uid(struct passwd *pw)
 				fatal("getgroups: %.100s", strerror(errno));
 		} else { /* user_groupslen == 0 */
 			free(user_groups);
+			user_groups = NULL;
 		}
+		user_groups_uid = pw->pw_uid;
 	}
 	/* Set the effective uid to the given (unprivileged) uid. */
 	if (setgroups(user_groupslen, user_groups) < 0)
@@ -131,37 +135,6 @@ temporarily_use_uid(struct passwd *pw)
 		    strerror(errno));
 }
 
-void
-permanently_drop_suid(uid_t uid)
-{
-#ifndef NO_UID_RESTORATION_TEST
-	uid_t old_uid = getuid();
-#endif
-
-	debug("permanently_drop_suid: %u", (u_int)uid);
-	if (setresuid(uid, uid, uid) < 0)
-		fatal("setresuid %u: %.100s", (u_int)uid, strerror(errno));
-
-#ifndef NO_UID_RESTORATION_TEST
-	/*
-	 * Try restoration of UID if changed (test clearing of saved uid).
-	 *
-	 * Note that we don't do this on Cygwin, or on Solaris-based platforms
-	 * where fine-grained privileges are available (the user might be
-	 * deliberately allowed the right to setuid back to root).
-	 */
-	if (old_uid != uid &&
-	    (setuid(old_uid) != -1 || seteuid(old_uid) != -1))
-		fatal("%s: was able to restore old [e]uid", __func__);
-#endif
-
-	/* Verify UID drop was successful */
-	if (getuid() != uid || geteuid() != uid) {
-		fatal("%s: euid incorrect uid:%u euid:%u (should be %u)",
-		    __func__, (u_int)getuid(), (u_int)geteuid(), (u_int)uid);
-	}
-}
-
 /*
  * Restores to the original (privileged) uid.
  */