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Re: stack overflow in getaddrinfo(3) with a small-sized stack in pthreads
Steffen Nurpmeso wrote in
<20211129173130.B55BA%steffen%sdaoden.eu@localhost>:
|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.
Ah ya the OPT RR also mentions MTU. Sorry.
--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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