[BusyBox] init blocks signals and forgets to clear signal mask before executing news processes

[Jean Wolter]

Hello,

init blocks signals (especially SIGHUP) and forgets to clear the
signal mask before calling execve. Therefore new processes never see
SIGHUP if they don't unblock it themself.

init_main:

	/* Set up sig handlers  -- be sure to
	 * clear all of these in run() */
	sigemptyset(&mask);
	sigaddset(&mask, SIGHUP);
	sigprocmask(SIG_BLOCK, &mask, NULL);

But there is no code in run clearing this procmask. As a temporary
workaround I have added the following:

--- init.c      9 Sep 2003 21:36:47 -0000       1.2
+++ init.c      21 Sep 2003 20:24:21 -0000      1.3
@@ -602,6 +602,8 @@
 
                /* Now run it.  The new program will take over this PID, 
                 * so nothing further in init.c should be run. */
+               sigemptyset(&omask);
+               sigprocmask(SIG_SETMASK, &omask, NULL);
                execv(cmdpath, cmd);
 
                /* We're still here?  Some error happened. */

I am sure there is a better fix for this problem.

Regards,
Jean