Hi Greg, On Thu, Jul 31, 2008 at 5:51 AM, Greg KH <greg@xxxxxxxxx> wrote: > On Wed, Jul 30, 2008 at 10:13:28PM +0530, Sukanto Ghosh wrote: >> Hi, >> >> In PCI DMA operation, a device (consider it to be bus-master) can >> directly transfer data to a memory location (some bus address, which >> is 1:1 mapped to physical address, in case of x86). >> Consider that a device driver asks the device to copy n bytes from its >> buffer to the kernel buffer at bus address X. But due to some fault in >> the device it starts writing to memory location Y, which is actually >> the kernel-buffer of some other device driver. Isn't this a potential >> security threat to the entire system ? How is it handled ? > > That's a fault of the hardware, nothing the os can do about that, sorry. > > Go complain to the vendor of the broken PCI device :) What about those days when there was a DMA controller ? Didn't the DMA controller control the addresses and the device sent only data ? Thanks and Regards, Sukanto -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
