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Re: stack overflow in getaddrinfo(3) with a small-sized stack in pthreads

Joerg Sonnenberger wrote in
 |On Mon, Nov 29, 2021 at 06:31:30PM +0100, Steffen Nurpmeso wrote:
 |> Joerg Sonnenberger wrote in
 |>  <>:
 |>|On Mon, Nov 29, 2021 at 08:38:35PM +0700, Robert Elz wrote:
 |>|> DNS queries (via UDP) are limited to max 512, as that is what the
 |>|> protocol always required, so can be handled by everything (or should \
 |>|> be).
 |>|Strictly speaking, it is the minimum MTU every IPv4 implementation is
 |>|supposed to allow. IPv6 bumped it to 1280.
 |> RFC 1035 says
 |>   2.3.4. Size limits
 |>   ...
 |>   UDP messages    512 octets or less
 |> If no EDNS is in use the answer should be pretty small also.
 |> Also see RFC 2671, but i have forgotten about all that.
 |Both are predate IPv6 by ages and don't actually disagree with what I am

No.  I documented 

        * \var conf_edns_size
        * The default is 1280 (RFC 2671, 4.5.1.).
        * The minimum is 1024 (RFC 3226, 3.; note: not 1220!).
        * The maximum is 65000.

..'just wanted to say that FreeBSD fixed aspects of FIONREAD just
one or two (or so) weeks ago.

 --End of <>

|Der Kragenbaer,                The moon bear,
|der holt sich munter           he cheerfully and one by one
|einen nach dem anderen runter  wa.ks himself off
|(By Robert Gernhardt)

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