Atomic mmap replacement

[Ken Brown]

Hi Corinna,

On 12/17/2024 11:38 AM, Corinna Vinschen via Cygwin wrote:
> Ideally a separate patch.  If you see a chance to send it to cygwin-patches
> this week, we can even merge it into 3.5.5, which I'm planning to release
> end of this week (after that --> vacation :)))
That should be no problem.  By the way, I think I found a second bug. 
Shouldn't mmap:649 be

(*)  if (u_addr > (caddr_t) addr || u_len < len

instead of

(**)  if (u_addr > (caddr_t) addr || u_addr + len < (caddr_t) addr + len

?

If the first condition in (**) fails, then u_addr == addr, so the second 
condition is automatically false.  But what we want to be testing at 
this point is whether the matched region is big enough, as in (*).  Or 
am I confused?

Ken