> > "that allows supervisor mode programs to optionally set user-space > > memory mappings so that access to those mappings from supervisor mode > > will cause a trap. This makes it harder for malicious programs to > > "trick" the kernel into using instructions or data from a user-space > > program" > > OK, probably. I thought it's triggered in access_ok(), and tried to > figure out why. But seems we should do something to check this in > access_ok(), otherwise the logic of clear_user/_clear_user is not so > reasonable. Anyway, I have learned it, thanks a lot for digging it out. > > By the way, I can't open above wiki article, found below commit from > hpa. Maybe we can add some into log to tell this, not strong opinin, > leave it to you. Yes, now that we know the root cause I'll add some more details to the patch description and resend -- thanks Baoquan!
