[Gllug] Anyone having broadband (probably PlusNet) problems today?

[Nix]

On Mon, 28 Mar 2005, Russell Howe wrote:
> Compare this to some other devices (RAID cards? I don't know) which
> actually have a microprocessor onboard, and whose drivers upload binary
> firmware on startup in order that the hardware is usable. This code runs
> on the hardware itself and not as part of the operating system.

Well, one major example of this sort of hardware is SymBIOS SCSI cards
(sym53c7xx and 8xx, for starters).

> Contrast this with firmware, which doesn't share the kernel's address
> space and which interacts with the kernel over a well-defined interface
> (e.g. the PCI bus or USB). Sure, if the hardware of the card is capable,
> the firmware can do bad things, including data corruption, crashing
> (although only that piece of hardware would crash), DoS'ing the bus the
> hardware's connected to, perhaps, etc, but the scope of the harm caused
> is much more limited and outside of the OS's control, typically. Any
> vendor producing such firmware is unlikely to be very highly regarded!

Actaully, in general, if the hardware is DMA-capable, the firmware could
do anything in RAM it liked, including (if the firmware were malicious
or buggy) introducing security holes.

Disk controllers tend to be DMA-capable. :)

-- 
This is like system("/usr/funky/bin/perl -e 'exec sleep 1'");
   --- Peter da Silva
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