On 10/06/15 01:49, Michael S. Tsirkin wrote: > On Tue, Oct 06, 2015 at 01:09:55AM +0300, Vladislav Zolotarov wrote: >> How about instead of trying to invent the wheel just go and attack the >> problem >> directly just like i've proposed already a few times in the last days: >> instead >> of limiting the UIO limit the users that are allowed to use UIO to privileged >> users only (e.g. root). This would solve all clearly unresolvable issues u >> are >> raising here all together, wouldn't it? > No - root or no root, if the user can modify the addresses in the MSI-X > table and make the chip corrupt random memory, this is IMHO a non-starter.
Michael, how this or any other related patch is related to the problem u r describing? The above ability is there for years and if memory serves me well it was u who wrote uio_pci_generic with this "security flaw". ;) This patch in general only adds the ability to receive notifications per MSI-X interrupt and it has nothing to do with the ability to reprogram the MSI-X related registers from the user space which was always there. > > And tainting kernel is not a solution - your patch adds a pile of > code that either goes completely unused or taints the kernel. > Not just that - it's a dedicated userspace API that either > goes completely unused or taints the kernel. > >>> -- >>> MST