Changeset 3621 in MondoRescue for branches/3.3/mindi-busybox/libbb/change_identity.c

Timestamp:

Dec 20, 2016, 4:07:32 PM (7 years ago)

Author:

Bruno Cornec

Message:

New 3?3 banch for incorporation of latest busybox 1.25. Changing minor version to handle potential incompatibilities.

Location:

branches/3.3

Files:

• . (copied) (copied from branches/3.2 )
• mindi-busybox/libbb/change_identity.c (modified) (1 diff)

branches/3.3/mindi-busybox/libbb/change_identity.c

@@ -34 +34 @@
 void FAST_FUNC change_identity(const struct passwd *pw)
 {
-    if (initgroups(pw->pw_name, pw->pw_gid) == -1)
+    int res;
+
+    res = initgroups(pw->pw_name, pw->pw_gid);
+    endgrent(); /* helps to close a fd used internally by libc */
+
+    if (res != 0) {
+        /*
+         * If initgroups() fails because a system call is unimplemented
+         * then we are running on a Linux kernel compiled without multiuser
+         * support (CONFIG_MULTIUSER is not defined).
+         *
+         * If we are running without multiuser support *and* the target uid
+         * already matches the current uid then we can skip the change of
+         * identity.
+         */
+        if (errno == ENOSYS && pw->pw_uid == getuid()) {
+            return;
+        }
+
         bb_perror_msg_and_die("can't set groups");
-    endgrent(); /* helps to close a fd used internally by libc */
+    }
+
     xsetgid(pw->pw_gid);
     xsetuid(pw->pw_uid);