From c8ef6fff3b051ef970a439115e1630105f87bdce Mon Sep 17 00:00:00 2001
From: Ernestas Kulik <ekulik@redhat.com>
Date: Mon, 10 Jun 2019 13:38:34 +0200
Subject: [PATCH] cli: run-command: Replace use of vfork() with fork()

vfork() replacing fork() was most likely an optimization, but, over
time, changes were added that violate the contract, i.e. the code
started going things other than exec and exit:
https://pubs.opengroup.org/onlinepubs/009695399/functions/vfork.html.

posix_spawn(), as recommended by Clang, would not be a suitable
replacement, as we need to call tcsetpgrp() on the child, doing which
after exec is too late if the goal is to avoid races.

Signed-off-by: Ernestas Kulik <ekulik@redhat.com>
---
 src/cli/run-command.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/cli/run-command.c b/src/cli/run-command.c
index 232f725..a8416a0 100644
--- a/src/cli/run-command.c
+++ b/src/cli/run-command.c
@@ -53,10 +53,10 @@ static void start_command(struct command *cmd)
 
   fflush(NULL);
 
-  cmd->pid = vfork();
+  cmd->pid = fork();
   if (cmd->pid < 0)
   {
-    perror_msg_and_die("vfork");
+    perror_msg_and_die("fork");
   }
   if (cmd->pid == 0)
   {
@@ -85,7 +85,7 @@ static void start_command(struct command *cmd)
     signal(SIGTTOU, SIG_DFL);
 
     execvp(cmd->argv[0], cmd->argv);
-    /* Better to use _exit (not exit) after vfork:
+    /* Better to use _exit (not exit) after fork:
      * we don't want to mess up parent's memory state
      * by running libc cleanup routines.
      */
-- 
2.21.0