CBMEM console: Prevent buffer overrun

Make sure memcpy target and a possible message telling log was truncated
stay within the allocated region for CBMEM console.

This fixes observed CBMEM corruption on platforms that do not use CBMEM
console during romstage. Those platforms will need an additional fix to
reset cursor position to zero on s3 resume.

Change-Id: I76501ca3afc716545ca76ebca1119995126a43f8
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/4292
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Idwer Vollering <vidwer@gmail.com>
Reviewed-by: Martin Roth <martin.roth@se-eng.com>
1 file changed