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On 4/21/22 3:49 PM, Dmitry Karpov via c-ares wrote:<br>
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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><br>
I recently stepped on an issue with curl using c-ares
ares_getaddrinfo() with PF_UNSPEC family, when AAAA response
from DNS server contained some bad data resulting into
ARES_EBADRESP status code whereas A response was good.<br>
<br>
The problem was that when AAAA response was the last received,
it made c-ares to ignore previously received good A response
and fail the host resolution with ARES_EBADRESP status code.<br>
But if A response was the last received, then c-ares ignored
the bad AAAA response and the host resolution was successful.<br>
<br>
I looked at the c-ares code, and found the problem in the
host_callback() function<span
style="font-size:9.5pt;font-family:Consolas;color:#880000">
</span> (src\lib\ares_getaddrinfo.c: 528)<br>
<br>
<o:p></o:p></p>
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...<br>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">When there are no remaining queries, the
ARES_EBADRESP parsing error is reported immediately, even
though the previous query might be successful.<br>
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<p class="MsoNormal"><span
style="font-size:9.5pt;font-family:Consolas;color:black">
</span>I am also attaching a patch file with the potential
fix.<br>
<br>
Thanks,<br>
Dmitry Karpov<br>
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<br>
<br>
Thanks! This patch has been applied to main.<br>
<br>
-Brad<br>
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