3 ms·
1. Hardware that batches DMA and replays it: a full device reset when the driver first initializes (before enabling bus mastering) should fix this, right? 2. D
by sounds 15y ago
1. Hardware that batches DMA and replays it: a full device reset when the driver first initializes (before enabling bus mastering) should fix this, right?
2. Drivers that depend on this: which ones? Are they hard to fix?
Obligatory: I'm a kernel developer so I may be overly optimistic, but isn't this a security problem, at least in one sense? (That is, a malicious device may try to use bus mastering to attack a running kernel.)
- kelnos 15y agoIf someone has the ability to get a malicious device into your system, likely they have the ability to screw you over in more reliable ways too.
- sounds 15y agoYes, physical access is game-over. However, what if the malicious device is actually a compromised but popular vendor who ships malicious firmware? That wouldn't be a stretch. Resetting devices and fixing drivers isn't a huge win, but it's still an improvement. Like ASLR doesn't actively prevent buffer overflows - it just makes attacks more difficult.