6 ms·

I expect the developers who write the kernel mode drivers to be much more competent and senior than those who write the flashy, slow GUIs that come with them. Y

by hhsbz 5y ago

I expect the developers who write the kernel mode drivers to be much more competent and senior than those who write the flashy, slow GUIs that come with them. Yes, naive assumption, but still!

aYsY4dDQ2NrcNzA 5y ago
Speaking as someone who worked at major software companies, on projects which included multiple kernel drivers: You are sorely mistaken.
- jeffbee 5y ago
  I would say that the higher you get up the privilege level tree, the worse the software becomes. The people writing legacy BIOS extensions are the absolute bottom of the barrel.
  - glitchc 5y ago
    In modern software development, this is usually a task for the junior engineer as it's code the client never sees. Only in specific industries where the client is also highly technical (e.g. a data-acquisition component in an instrument) where the quality of the low-level code matters, would it be someone senior. In those cases, it usually matters a lot more than the UI.
zenexer 5y ago
I wish that were the case—I also wish it were the case that “senior” meant “competent.” Judging by the number of device drivers I’ve had cause serious problems, especially with consumer gaming hardware (as is the case here), I don’t think it’s safe to make any assumptions about the quality of drivers. For anyone else reading this who’s feeling smug because they would never buy such a device: you don’t need to; only the attacker needs to. Windows will happily download and install the drivers automatically the first time the device is plugged in.
- vlovich123 5y ago
  It's also not about seniority or competence. Writing kernel mode drivers is being given the task of juggling running chainsaws with real chains while on a balancing board. "Success" is declared when you're able to do this in a lab without there being an issue, ignoring the fact that in the real world there are dodgeballs being thrown at you. Also, no one I've ever worked with writing them has ever wanted to maintain & improve the quality of the drivers they wrote - they wanted to move on to "interesting" work as quickly as possible. This includes myself. The work isn't interesting, fun & usually not important to the business. In this case, why does a mouse driver need to live in the kernel in the first place? Microsoft should be improving the HID layer to make that unnecessary.
- arghwhat 5y ago
  They don't even need to buy the device, they just need something presenting that PID/VID. Foe a $2 example, see: https://github.com/chris408/digispark-usbkey-board https://github.com/chris408/digispark-usbkey-board (PID/VID set here: https://github.com/chris408/digispark-usbkey-board/blob/6f0a923deb2415043aa53a693ef6bee4092f9b86/usbconfig.h#L232 https://github.com/chris408/digispark-usbkey-board/blob/6f0a...). And yes, it can be much, much smaller than this.
the8472 5y ago
Exhibit A: Turing-complete font hinting language evaluated in kernel mode. Found to be exploitable. https://googleprojectzero.blogspot.com/2015/07/one-font-vulnerability-to-rule-them-all.html https://googleprojectzero.blogspot.com/2015/07/one-font-vuln...
jnwatson 5y ago
Not at all. The only thing going in favor of the kernel mode drivers is that they have to pass Microsoft's approval process.

by hhsbz 5y ago

I expect the developers who write the kernel mode drivers to be much more competent and senior than those who write the flashy, slow GUIs that come with them. Yes, naive assumption, but still!

aYsY4dDQ2NrcNzA 5y ago

Speaking as someone who worked at major software companies, on projects which included multiple kernel drivers: You are sorely mistaken.

jeffbee 5y ago
I would say that the higher you get up the privilege level tree, the worse the software becomes. The people writing legacy BIOS extensions are the absolute bottom of the barrel.
- glitchc 5y ago
  In modern software development, this is usually a task for the junior engineer as it's code the client never sees. Only in specific industries where the client is also highly technical (e.g. a data-acquisition component in an instrument) where the quality of the low-level code matters, would it be someone senior. In those cases, it usually matters a lot more than the UI.

zenexer 5y ago

I wish that were the case—I also wish it were the case that “senior” meant “competent.” Judging by the number of device drivers I’ve had cause serious problems, especially with consumer gaming hardware (as is the case here), I don’t think it’s safe to make any assumptions about the quality of drivers. For anyone else reading this who’s feeling smug because they would never buy such a device: you don’t need to; only the attacker needs to. Windows will happily download and install the drivers automatically the first time the device is plugged in.

vlovich123 5y ago
It's also not about seniority or competence. Writing kernel mode drivers is being given the task of juggling running chainsaws with real chains while on a balancing board. "Success" is declared when you're able to do this in a lab without there being an issue, ignoring the fact that in the real world there are dodgeballs being thrown at you. Also, no one I've ever worked with writing them has ever wanted to maintain & improve the quality of the drivers they wrote - they wanted to move on to "interesting" work as quickly as possible. This includes myself. The work isn't interesting, fun & usually not important to the business. In this case, why does a mouse driver need to live in the kernel in the first place? Microsoft should be improving the HID layer to make that unnecessary.
arghwhat 5y ago
They don't even need to buy the device, they just need something presenting that PID/VID. Foe a $2 example, see: https://github.com/chris408/digispark-usbkey-board https://github.com/chris408/digispark-usbkey-board (PID/VID set here: https://github.com/chris408/digispark-usbkey-board/blob/6f0a923deb2415043aa53a693ef6bee4092f9b86/usbconfig.h#L232 https://github.com/chris408/digispark-usbkey-board/blob/6f0a...). And yes, it can be much, much smaller than this.

the8472 5y ago

Exhibit A: Turing-complete font hinting language evaluated in kernel mode. Found to be exploitable. https://googleprojectzero.blogspot.com/2015/07/one-font-vulnerability-to-rule-them-all.html https://googleprojectzero.blogspot.com/2015/07/one-font-vuln...

jnwatson 5y ago

Not at all. The only thing going in favor of the kernel mode drivers is that they have to pass Microsoft's approval process.