From 7adff31cbb521d52c31a3e6e2447db8bcd8e3784 Mon Sep 17 00:00:00 2001
From: Daniel Lezcano <dlezcano@fr.ibm.com>
Date: Thu, 8 Apr 2010 09:44:23 +0200
Subject: [PATCH] fork/exec after attach

The command to attach has to be fork/exec.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
---
 src/lxc/lxc_attach.c | 62 +++++++++++++++++++++++++++++++++-----------
 1 file changed, 47 insertions(+), 15 deletions(-)

diff --git a/src/lxc/lxc_attach.c b/src/lxc/lxc_attach.c
index a012c2c6e..bae76ed4e 100644
--- a/src/lxc/lxc_attach.c
+++ b/src/lxc/lxc_attach.c
@@ -25,6 +25,9 @@
 #include <errno.h>
 #include <sys/param.h>
 #include <pwd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
 #include "commands.h"
 #include "arguments.h"
 #include "namespace.h"
@@ -106,29 +109,58 @@ int main(int argc, char *argv[], char *envp[])
 		return -1;
 	}
 
-	if (my_args.argc) {
-		execve(my_args.argv[0], my_args.argv, envp);
-		SYSERROR("failed to exec '%s'", my_args.argv[0]);
+	pid = fork();
+
+	if (pid < 0) {
+		SYSERROR("failed to fork");
 		return -1;
 	}
 
-	uid = getuid();
+	if (pid) {
+		int status;
+
+	again:
+		if (waitpid(pid, &status, 0) < 0) {
+			if (errno == EINTR)
+				goto again;
+			SYSERROR("failed to wait '%d'", pid);
+			return -1;
+		}
+
+		if (WIFEXITED(status))
+			return WEXITSTATUS(status);
 
-	passwd = getpwuid(uid);
-	if (!passwd) {
-		SYSERROR("failed to get passwd entry for uid '%d'", uid);
 		return -1;
 	}
 
-	{
-		char *const args[] = {
-			passwd->pw_shell,
-			NULL,
-		};
+	if (!pid) {
+
+		if (my_args.argc) {
+			execve(my_args.argv[0], my_args.argv, envp);
+			SYSERROR("failed to exec '%s'", my_args.argv[0]);
+			return -1;
+		}
+
+		uid = getuid();
+
+		passwd = getpwuid(uid);
+		if (!passwd) {
+			SYSERROR("failed to get passwd "		\
+				 "entry for uid '%d'", uid);
+			return -1;
+		}
+
+		{
+			char *const args[] = {
+				passwd->pw_shell,
+				NULL,
+			};
+
+			execve(args[0], args, envp);
+			SYSERROR("failed to exec '%s'", args[0]);
+			return -1;
+		}
 
-		execve(args[0], args, envp);
-		SYSERROR("failed to exec '%s'", args[0]);
-		return -1;
 	}
 
 	return 0;
-- 
2.47.2