revert last two commits. vfork cannot be used in subroutine,

it trashes stack on return

3 files changed, 16 insertions, 4 deletions

diff --git a/networking/ifupdown.c b/networking/ifupdown.c
index 8caff3f4d..c12391863 100644
--- a/networking/ifupdown.c
+++ b/networking/ifupdown.c
@@ -1008,9 +1008,12 @@ static int popen2(FILE **in, FILE **out, char *command, char *param)
         xpiped_pair(outfd);
 
         fflush(NULL);
-        pid = xvfork();
+        pid = vfork();
 
-        if (pid == 0) { /* child */
+        switch (pid) {
+        case -1:  /* failure */
+                bb_perror_msg_and_die("vfork");
+        case 0:  /* child */
                 /* NB: close _first_, then move fds! */
                 close(infd.wr);
                 close(outfd.rd);
diff --git a/networking/inetd.c b/networking/inetd.c
index 0028078db..08c09953b 100644
--- a/networking/inetd.c
+++ b/networking/inetd.c
@@ -1303,7 +1303,7 @@ int inetd_main(int argc ATTRIBUTE_UNUSED, char **argv)
                                         pid = vfork();
 
                                 if (pid < 0) { /* fork error */
-                                        bb_perror_msg(BB_MMU ? "vfork" + 1 : "vfork");
+                                        bb_perror_msg("fork");
                                         sleep(1);
                                         restore_sigmask(&omask);
                                         maybe_close(accepted_fd);
diff --git a/networking/sendmail.c b/networking/sendmail.c
index c195cc021..1c23ca290 100644
--- a/networking/sendmail.c
+++ b/networking/sendmail.c
@@ -120,6 +120,15 @@ static void signal_handler(int signo)
 #undef err
 }
 
+/* libbb candidate */
+static pid_t vfork_or_die(void)
+{
+        pid_t pid = vfork();
+        if (pid < 0)
+                bb_perror_msg_and_die("vfork");
+        return pid;
+}
+
 static void launch_helper(const char **argv)
 {
         // setup vanilla unidirectional pipes interchange
@@ -128,7 +137,7 @@ static void launch_helper(const char **argv)
 
         xpipe(pipes);
         xpipe(pipes+2);
-        helper_pid = xvfork();
+        helper_pid = vfork_or_die();
         idx = (!helper_pid) * 2;
         xdup2(pipes[idx], STDIN_FILENO);
         xdup2(pipes[3-idx], STDOUT_FILENO);