[coreboot] [RFC] Null pointer trap?
c-d.hailfinger.devel.2006 at gmx.net
Fri Nov 7 15:24:33 CET 2008
v3 does not have any mechanism to detect NULL pointers used by accident.
I propose to fill the zero page (0x0-0xfff) with a special POISON_BYTE,
maybe 0x6b. Furthermore, I'd like to make sure passing a NULL pointer
(or something near it) to as a string to printk will be very visible in
*(char *)0 = "ERROR NULL POINTER DEREFERENCE!\n";
The C statement above would cause a nice print everytime someone
referenced the first 32 bytes in %s.
Another way to do this is extending the non-NULL check in printk to
cover the whole zero page.
More information about the coreboot