AF_INET6 lookups breaks AF_INET lookups

[Thorsten Kukuk <kukuk at suse dot de>]

Hi,

glibc 2.3 has a servery bug in the resolver code. It seems, that
a AF_INET6 lookup for a hostname will change some internal data, so
that AF_INET lookups are not longer possible for all hostnames.

I append my test program, the hostname I can reproduce it with is
www.lufthansa.com. I do 3 gethostbyname2 lookups: One with AF_INET,
this works, one with AF_INET6, this does not work as expected. Now
I do again an AF_INET lookup and now this also fails. With glibc 2.2.5
it works fine.

The output of the testprogram:

Using gethostbyname2 (www.lufthansa.com, AF_INET): 53.122.207.1    www.lufthansa.com
Using gethostbyname2 (www.lufthansa.com, AF_INET6): www.lufthansa.com not found
Using gethostbyname2 (www.lufthansa.com, AF_INET): www.lufthansa.com not found


Any ideas where we break this? It must be the nss_dns code or the
libresolv code, but I haven't found it yet.

  Thorsten

-- 
Thorsten Kukuk       http://www.suse.de/~kukuk/        kukuk@suse.de
SuSE Linux AG        Deutschherrnstr. 15-19        D-90429 Nuernberg
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Attachment: hostbug.c
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