Re: [coreboot] [PATCH] v3: Improve printk reliability

[Mathias Krause]

Carl-Daniel Hailfinger wrote:
> @@ -194,9 +195,15 @@
>    		s = va_arg(args, char *);
>    		if (!s)
>    			s = "<NULL>";
> 	/* Catch almost-NULL pointers as well */
> 	if ((size_t)s < 0x400)
> 		s = "<almost NULL>";
>
> len = strnlen(s, precision);
>
> 	for (i = 0; i < len; ++i)
> 		if (!isprint(*s[i]))
> 			s = "<GARBAGE>";

No offense, but isn't there a break missing in the loop when we assign s
to be "<GARBAGE>"? Otherwise we may access invalid data if len is
greater than strlen("<GARBAGE>") because we have changed the base we're
looking at.
> 	if (!(flags & LEFT))
> 		while (len < field_width--)
> 			tx_byte(' ', arg), count++;

Mathias