Dominic Marks wrote: > Hello, > > In vm_map.c, in the vm_map_insert(...) function there is the following > piece of code which checks if the addresses supplied to the function are > valid: > > ** > if ((start < map->min_offset) || (end > map->max_offset) || > (start >= end)) > return (KERN_INVALID_ADDRESS); > ** > > Specifically, I am interested in the final comparison. Is it possible > that start == end could ever be correct? Do zero sized entries ever get > inserted? (I don't see why you would ever wish to do this, please > explain it to me if there is a reason).
That would most likely be a case of defensive programming, especially in case of a sign wraparound problem or the like. No, inserting a zero-length map entry isn't valid and the defensive case comes for free. Cheers, -Peter -- Peter Wemm - [EMAIL PROTECTED]; [EMAIL PROTECTED]; [EMAIL PROTECTED] "All of this is for nothing if we don't go to the stars" - JMS/B5 To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
