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From c8ef6fff3b051ef970a439115e1630105f87bdce Mon Sep 17 00:00:00 2001
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From: Ernestas Kulik <ekulik@redhat.com>
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Date: Mon, 10 Jun 2019 13:38:34 +0200
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Subject: [PATCH] cli: run-command: Replace use of vfork() with fork()
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vfork() replacing fork() was most likely an optimization, but, over
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time, changes were added that violate the contract, i.e. the code
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started going things other than exec and exit:
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https://pubs.opengroup.org/onlinepubs/009695399/functions/vfork.html.
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posix_spawn(), as recommended by Clang, would not be a suitable
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replacement, as we need to call tcsetpgrp() on the child, doing which
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after exec is too late if the goal is to avoid races.
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Signed-off-by: Ernestas Kulik <ekulik@redhat.com>
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---
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src/cli/run-command.c | 6 +++---
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1 file changed, 3 insertions(+), 3 deletions(-)
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diff --git a/src/cli/run-command.c b/src/cli/run-command.c
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index 232f725..a8416a0 100644
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--- a/src/cli/run-command.c
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+++ b/src/cli/run-command.c
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@@ -53,10 +53,10 @@ static void start_command(struct command *cmd)
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fflush(NULL);
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- cmd->pid = vfork();
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+ cmd->pid = fork();
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if (cmd->pid < 0)
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{
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- perror_msg_and_die("vfork");
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+ perror_msg_and_die("fork");
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}
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if (cmd->pid == 0)
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{
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@@ -85,7 +85,7 @@ static void start_command(struct command *cmd)
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signal(SIGTTOU, SIG_DFL);
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execvp(cmd->argv[0], cmd->argv);
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- /* Better to use _exit (not exit) after vfork:
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+ /* Better to use _exit (not exit) after fork:
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* we don't want to mess up parent's memory state
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* by running libc cleanup routines.
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*/
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--
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2.21.0
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