Test 1083 fails when configured with --enable-ares

[Kangie]

I did this

$ ./configure --prefix=/usr --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --mandir=/usr/share/man --infodir=/usr/share/info --datadir=/usr/share --sysconfdir=/etc --localstatedir=/var/lib --datarootdir=/usr/share --disable-dependency-tracking --disable-silent-rules --disable-static --docdir=/usr/share/doc/curl-7.88.1-r2 --htmldir=/usr/share/doc/curl-7.88.1-r2/html --with-sysroot=/ --libdir=/usr/lib64 --without-ca-fallback --with-ca-bundle=/etc/ssl/certs/ca-certificates.crt --without-gnutls --without-mbedtls --without-nss --without-rustls --with-ssl --with-ca-path=/etc/ssl/certs --with-default-ssl-backend=openssl --disable-alt-svc --enable-crypto-auth --enable-dict --disable-ech --enable-file --enable-ftp --disable-gopher --disable-hsts --enable-http --enable-imap --disable-ldap --disable-ldaps --enable-ntlm --disable-ntlm-wb --enable-pop3 --enable-rt --enable-rtsp --disable-smb --without-libssh2 --enable-smtp --disable-telnet --enable-tftp --enable-tls-srp --enable-ares --enable-cookies --enable-dateparse --enable-dnsshuffle --enable-doh --enable-symbol-hiding --enable-http-auth --enable-ipv6 --enable-largefile --enable-manual --enable-mime --enable-netrc --enable-progress-meter --enable-proxy --enable-socketpair --disable-sspi --disable-static --enable-pthreads --enable-threaded-resolver --disable-versioned-symbols --without-amissl --without-bearssl --without-brotli --without-fish-functions-dir --with-nghttp2 --without-hyper --without-libidn2 --without-gssapi --without-libgsasl --without-libpsl --without-msh3 --without-nghttp3 --without-ngtcp2 --without-quiche --without-librtmp --without-schannel --without-secure-transport --without-test-caddy --without-test-httpd --without-test-nghttpx --disable-websockets --without-winidn --without-wolfssl --with-zlib --with-zstd --with-test-nghttpx=/usr/bin/nghttpx
$  make -j16 && make test -j16 TFLAGS="-n -v -a -k -am -p -d 1083"

I expected the following

Test 1083 should pass. When configured without ares the test passes successfully.

curl/libcurl version

curl 7.88.1 (x86_64-pc-linux-gnu) libcurl/7.88.1 OpenSSL/3.0.8 zlib/1.2.13 c-ares/1.19.0 nghttp2/1.52.0
Release-Date: 2023-02-20

c-ares version

1.19.0

operating system

Linux obsidian 6.2.0-gentoo #3 SMP PREEMPT_DYNAMIC Fri Feb 24 23:33:12 AEDT 2023 x86_64 AMD Ryzen 7 3700X 8-Core Processor AuthenticAMD GNU/Linux

[jay]

Please include the test output.

[bagder]

Even when there is an entry for ip6-localhost in /etc/hosts, this source code line surprisingly returns an error:

curl/lib/cf-socket.c

Line 498 in 06f65f7

rc = Curl_resolv(data, dev, 0, FALSE, &h);

[Kangie]

As requested: build.log.txt

What I see with ares enabled:

kangie@obsidian /data/development/temp/curl (ip6-localhost*) $ src/curl -g 'http://[::1]/'                                 
curl: (7) Failed to connect to ::1 port 80 after 0 ms: Couldn't connect to server
kangie@obsidian /data/development/temp/curl (ip6-localhost*) $ src/curl -g 'http://[::1]/' --interface localhost           
RC = 0
curl: (7) Failed to connect to ::1 port 80 after 0 ms: Couldn't connect to server
kangie@obsidian /data/development/temp/curl (ip6-localhost*) $ src/curl -g 'http://[::1]/' --interface ip6-localhost       
RC = -1
curl: (45) Couldn't bind to 'ip6-localhost'
kangie@obsidian /data/development/temp/curl (ip6-localhost*) $ doas src/curl -g 'http://[2607:f8b0:4002:81a::2003]/' --interface localhost    
RC = 0
curl: (7) Failed to connect to 2607:f8b0:4002:81a::2003 port 80 after 0 ms: Couldn't connect to server
kangie@obsidian /data/development/temp/curl (ip6-localhost*) $ doas src/curl -g 'http://[2607:f8b0:4002:81a::2003]/' --interface ip6-localhost
RC = -1
curl: (45) Couldn't bind to 'ip6-localhost'
kangie@obsidian /data/development/temp/curl (ip6-localhost*) $ doas src/curl -g 'http://[2607:f8b0:4002:81a::2003]/' --interface localhost --ipv6
RC = 0
curl: (7) Failed to connect to 2607:f8b0:4002:81a::2003 port 80 after 0 ms: Couldn't connect to server
kangie@obsidian /data/development/temp/curl (ip6-localhost*) $ doas src/curl -g 'http://[2607:f8b0:4002:81a::2003]/'                             
<!DOCTYPE html>
     ...
kangie@obsidian /data/development/temp/curl (ip6-localhost*) $ doas src/curl -g 'http://[::1]/' --interface "::1"
RC = 0
curl: (7) Failed to connect to ::1 port 80 after 0 ms: Couldn't connect to server

So we're failing to resolve ip6-localhost and can't work out which interface we're supposed to bind to.

Through judicious printf debugging, It looks like we're erroring on interface resolution here:

curl/lib/hostip.c

Lines 785 to 788 in 06f65f7

	/* First, check that we haven't received the info by now */
	result = Curl_resolv_check(data, &dns);
	if(result) /* error detected */
	return CURLRESOLV_ERROR;

I don't have much to add here, will have to leave my troubleshooting at that, gotta get back to work and moving for a while so I'll leave this with you!