On 12/18/2024 9:28 AM, Corinna Vinschen via Cygwin wrote:
Hi Ken,
On Dec 17 15:23, Ken Brown via Cygwin wrote:
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?
u_addr could be < addr. We have two areas, the free area in u_addr and
u_len, and the requested area in addr and len.
So we have to check that addr is >= u_addr and addr + len is <= u_len:
|----------------------------------------------------|
u_addr u_addr + u_len
|--------------------|
addr addr + len
Make sense?
No, I'm still confused. I thought that the interval determined by
u_addr and u_len was the intersection of the requested interval and the
whole interval of the mmap_record; this implies u_addr >= addr. Back in
the definition of mmap_record::match, we set low = max (addr,
get_address ()), and then on success we set m_addr = low. Doesn't that
imply m_addr >= addr? Sorry if I'm just being dense.
Ken
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