[PATCH] fix 2.4.x incorrect argv[0] for init

Erik Andersen
2003-10-01T18:56:20Z

In 2.4.x when someone specifies "init=/bin/foo" to select an
alternative binary to run instead of /sbin/init, argv[0] is not
to the correct value. This is a problem for programs such as
busybox that multiplex applications based on the value of
argv[0]. For example, even if you specify init=/bin/sh" on the
kernel command line, busybox will still receive "/sbin/init" as
argv[0], and will therefore run init rather than /bin/sh...

This problem was recently fixed in 2.6.x. This patch applies
the same fix to 2.4.x.

-Erik

--
Erik B. Andersen http://codepoet-consulting.com/
--This message was written using 73% post-consumer electrons--

--- orig/init/main.c 2003-08-30 10:50:15.000000000 -0600
+++ linux-2.4.22/init/main.c 2003-08-30 10:50:15.000000000 -0600
@@ -545,6 +545,12 @@
#endif
}

+static void run_init_process(char *init_filename)
+{
+ argv_init[0] = init_filename;
+ execve(init_filename, argv_init, envp_init);
+}
+
extern void prepare_namespace(void);

static int init(void * unused)
@@ -587,10 +593,12 @@
*/

if (execute_command)
- execve(execute_command,argv_init,envp_init);
- execve("/sbin/init",argv_init,envp_init);
- execve("/etc/init",argv_init,envp_init);
- execve("/bin/init",argv_init,envp_init);
- execve("/bin/sh",argv_init,envp_init);
+ run_init_process(execute_command);
+
+ run_init_process("/sbin/init");
+ run_init_process("/etc/init");
+ run_init_process("/bin/init");
+ run_init_process("/bin/sh");
+
panic("No init found. Try passing init= option to kernel.");
}