I'm confused.. so Wi-Fi chips run OSes inside them now?
SD cards have been running RTOSs for some time.
Remotely compromise devices by using bugs in Marvell Avastar Wi-Fi
11–20 of 51 posts
Re: Remotely compromise devices by using bugs in Marvell Avastar Wi-Fi
#12Re: Remotely compromise devices by using bugs in Marvell Avastar Wi-Fi
#13Earlier quoted context omitted.
SD cards have been running RTOSs for some time.
The cards themselves?! Or the readers?
Re: Remotely compromise devices by using bugs in Marvell Avastar Wi-Fi
#14Given that Wifi chips already have their own ARM CPU, at this point I'd rather have that CPU which already runs its own OS to just present as a network device to do NAT. Connect it to the fixed network, use a serial link - anything will do. At least, I'd rather have anything but the current alternative: a device on the PCI bus having DMA with a firmware I can't audit. Same thing with WWAN device by the way.
Not speaking specifically of the OP case, but CPU gets less and less involved in the datapath starting from a certain requirement of the max throughput. Insisting on it's going through the CPU still would raise the bar on the CPU (as a consequence, more fast RAM and increased overall power consumption, shorter battery life). > with a firmware I can't audit. In modern fast datapaths, there is a good deal of hardware a…
Yes, there would be a IO load.
Tradeoffs, as always.
For some applications, I want low latency and high throughput. For others, I want security.
Re: Remotely compromise devices by using bugs in Marvell Avastar Wi-Fi
#15Earlier quoted context omitted.
SD cards have been running RTOSs for some time.
The cards themselves?! Or the readers?
It’s the card itself fairly similar to how controllers work in HDD/SSDs basically they abstract the physical storage medium which allows them to use a wide range of flash memory on the backend while maintianing compatibility with the SD format.
While you can achieve the same abstraction in hardware it’s much easier and cheaper to simply pick a small micro controller and do all the black magic you need in software especially since the flash on some of these cards can be really really bad as it’s often the lowest grade flash or worse recycled memory that ends up being used which means you end up with chips that are 50-80% defected so the controller ensures that these sectors/cells aren’t used.
Re: Remotely compromise devices by using bugs in Marvell Avastar Wi-Fi
#16Earlier quoted context omitted.
The cards themselves?! Or the readers?
Cards: https://www.bunniestudios.com/blog/?page_id=3592
Wow. I wonder if my mental image of an RTOS on the devices is correct? I would've imagined there's some sort of firmware inside any device that communicates with a host, but when I hear RTOS I think of something fairly generic that would be deployed across a range of device types (like a Linux system but real time) rather than specialized firmware... is that accurate?
Re: Remotely compromise devices by using bugs in Marvell Avastar Wi-Fi
#17Earlier quoted context omitted.
The cards themselves?! Or the readers?
It’s the card itself fairly similar to how controllers work in HDD/SSDs basically they abstract the physical storage medium which allows them to use a wide range of flash memory on the backend while maintianing compatibility with the SD format. While you can achieve the same abstraction in hardware it’s much easier and cheaper to simply pick a small micro controller and do all the black magic you need in software esp…
Ahh I see, thanks!
Re: Remotely compromise devices by using bugs in Marvell Avastar Wi-Fi
#18Earlier quoted context omitted.
Cards: https://www.bunniestudios.com/blog/?page_id=3592
Wow. I wonder if my mental image of an RTOS on the devices is correct? I would've imagined there's some sort of firmware inside any device that communicates with a host, but when I hear RTOS I think of something fairly generic that would be deployed across a range of device types (like a Linux system but real time) rather than specialized firmware... is that accurate?
Embedded micro controllers are very common these days in a wide range of ICs most of them aren’t disclosed or accessible to their users their sole role is to abstract the physical IC and present what the customer expects this can be things like timers, flash memory or even microcontrollers themselves as well as more complex ICs that need to ensure some defined PHY like network or serial controllers.
Re: Remotely compromise devices by using bugs in Marvell Avastar Wi-Fi
#19Earlier quoted context omitted.
Wow. I wonder if my mental image of an RTOS on the devices is correct? I would've imagined there's some sort of firmware inside any device that communicates with a host, but when I hear RTOS I think of something fairly generic that would be deployed across a range of device types (like a Linux system but real time) rather than specialized firmware... is that accurate?
Embedded micro controllers are very common these days in a wide range of ICs most of them aren’t disclosed or accessible to their users their sole role is to abstract the physical IC and present what the customer expects this can be things like timers, flash memory or even microcontrollers themselves as well as more complex ICs that need to ensure some defined PHY like network or serial controllers.
That's what I expected but it sounds like these are specifically not that?
Re: Remotely compromise devices by using bugs in Marvell Avastar Wi-Fi
#20I'm confused.. so Wi-Fi chips run OSes inside them now?
A RTOS is not really an OS, just a super-fast way of dealing with I/O streams. More driver/firmware than OS, if you ask me. But some companies need fancy words for marketing, I guess.