[Bug?] init.c: problems if kernel gets console=null via cmdline

[Denis Vlasenko]

On Sunday 01 July 2007 21:25, Harald Küthe wrote:
> Hello list,
> 
> we have problems with the recent versions of busybox (1.5 and 1.6) when we start our kernel (2.4.34) without console.
> Some programs do not start e.g. samba server.
> When we link init to an older version of busybox thing get working.
> Debugging is difficult because the problem does not exist in a strace/gdb environement.
> It seems to be ok if I hack console_init() that it uses /dev/null as the console.
> 
> Any help / direction is appreciated.

Try this: in init.c, add "else" clause as shown below:

static void console_init(void)
{
        struct serial_struct sr;
        char *s;

        s = getenv("CONSOLE");
        if (!s) s = getenv("console");
        if (s) {
                int fd = open(s, O_RDWR | O_NONBLOCK | O_NOCTTY);
                if (fd >= 0) {
                        dup2(fd, 0);
                        dup2(fd, 1);
                        dup2(fd, 2);
                        while (fd > 2) close(fd--);
                }
                messageD(L_LOG, "console='%s'", s);
+        } else {
+               /* Make sure fd 0,1,2 are not closed */
+               bb_sanitize_stdio();
        }

If it helps, I will add it in 1.6.2.
--
vda