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Re: stack overflow in getaddrinfo(3) with a small-sized stack in pthreads
Joerg Sonnenberger wrote in
<YaUsJ3uwtQSJDFwY%bec.de@localhost>:
|On Mon, Nov 29, 2021 at 06:31:30PM +0100, Steffen Nurpmeso wrote:
|> Joerg Sonnenberger wrote in
|> <YaT9P6a+AlEm3w7h%bec.de@localhost>:
|>|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
|saying...
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.
|Joerg
--End of <YaUsJ3uwtQSJDFwY%bec.de@localhost>
--steffen
|
|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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