assertion failure in bind 9.16.2

As reported to SO:

> Hello there,
> 
> I'm running some dnsperf test against from in your testlab, and quite often i bind to crash with assertion failure.  
> 
> I'm running bind dnsperf with: dnsperf -f inet -t 10 -s <SANITIZED> -d dns_clear.txt -c 200 -T 4 -l 36000000 -q 5000 -S 1 (Attached dns_clear.txt, which is are reallife traffic dump from our prod bind servers). We're running CentOS Linux release 7.7.1908 (Core) in both test/prod.
> 
> 29-Apr-2020 15:45:27.651 general: critical: netaddr.c:365: INSIST(0) failed, back trace
> 29-Apr-2020 15:45:27.651 general: critical: #0 0x42b890 in ??
> 29-Apr-2020 15:45:27.651 general: critical: #1 0x7f033062cada in ??
> 29-Apr-2020 15:45:27.651 general: critical: #2 0x7f033064a3d3 in ??
> 29-Apr-2020 15:45:27.651 general: critical: #3 0x7f033064fcc0 in ??
> 29-Apr-2020 15:45:27.651 general: critical: #4 0x7f033064ff56 in ??
> 29-Apr-2020 15:45:27.651 general: critical: #5 0x7f033195feaa in ??
> 29-Apr-2020 15:45:27.651 general: critical: #6 0x7f033187c448 in ??
> 29-Apr-2020 15:45:27.651 general: critical: #7 0x7f0331972a40 in ??
> 29-Apr-2020 15:45:27.651 general: critical: #8 0x7f0330652ada in ??
> 29-Apr-2020 15:45:27.651 general: critical: #9 0x7f032edc2e65 in ??
> 29-Apr-2020 15:45:27.651 general: critical: #10 0x7f032e6cd88d in ??
> 29-Apr-2020 15:45:27.651 general: critical: exiting (due to assertion failure)
> 
> I've several coredumps.. Do you guys have a place where i can upload them?
> 
> [root@srv07 data]# ls -lh
> total 5.7G
> -rw-------. 1 named named 1.7G Apr 22 08:48 core.11065
> -rw-------. 1 named named 1.6G Apr 22 12:58 core.11877
> -rw-------. 1 named named 2.6G Apr 21 21:17 core.126377
> -rw-------. 1 named named 1.4G Apr 29 15:45 core.15168
> -rw-------. 1 named named 166M Apr 27 17:03 core.21234
> -rw-------. 1 named named 175M Apr 27 17:07 core.21301
> -rw-------. 1 named named 2.2G Apr 21 15:33 core.72474
> 
> [root@srv07 log]# named -V
> BIND 9.16.2 (Stable Release) <id:b310dc7>
> running on Linux x86_64 3.10.0-1062.18.1.el7.x86_64 #1 SMP Tue Mar 17 23:49:17 UTC 2020
> built by make with '--build=x86_64-redhat-linux-gnu' '--host=x86_64-redhat-linux-gnu' '--program-prefix=' '--disable-dependency-tracking' '--prefix=/opt/isc/isc-bind/root/usr' '--exec-prefix=/opt/isc/isc-bind/root/usr' '--bindir=/opt/isc/isc-bind/root/usr/bin' '--sbindir=/opt/isc/isc-bind/root/usr/sbin' '--sysconfdir=/etc/opt/isc/isc-bind' '--datadir=/opt/isc/isc-bind/root/usr/share' '--includedir=/opt/isc/isc-bind/root/usr/include' '--libdir=/opt/isc/isc-bind/root/usr/lib64' '--libexecdir=/opt/isc/isc-bind/root/usr/libexec' '--localstatedir=/var/opt/isc/isc-bind' '--sharedstatedir=/var/opt/isc/isc-bind/lib' '--mandir=/opt/isc/isc-bind/root/usr/share/man' '--infodir=/opt/isc/isc-bind/root/usr/share/info' '--disable-static' '--enable-dnstap' '--with-pic' '--with-gssapi' '--with-json-c' '--with-libtool' '--with-libxml2' '--without-lmdb' '--with-docbook-xsl=/usr/share/sgml/docbook/xsl-stylesheets' '--with-python' 'build_alias=x86_64-redhat-linux-gnu' 'host_alias=x86_64-redhat-linux-gnu' 'CFLAGS=-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic' 'LDFLAGS= -L/opt/isc/isc-bind/root/usr/lib64' 'PKG_CONFIG_PATH=:/opt/isc/isc-bind/root/usr/lib64/pkgconfig:/opt/isc/isc-bind/root/usr/share/pkgconfig'
> compiled by GCC 4.8.5 20150623 (Red Hat 4.8.5-39)
> compiled with OpenSSL version: OpenSSL 1.0.2k-fips  26 Jan 2017
> linked to OpenSSL version: OpenSSL 1.0.2k-fips  26 Jan 2017
> compiled with libxml2 version: 2.9.1
> linked to libxml2 version: 20901
> compiled with json-c version: 0.11
> linked to json-c version: 0.11
> compiled with zlib version: 1.2.7
> linked to zlib version: 1.2.7
> compiled with protobuf-c version: 1.3.2
> linked to protobuf-c version: 1.3.2
> threads support is enabled
> 
> default paths:
>   named configuration:  /etc/opt/isc/isc-bind/named.conf
>   rndc configuration:   /etc/opt/isc/isc-bind/rndc.conf
>   DNSSEC root key:      /etc/opt/isc/isc-bind/bind.keys
>   nsupdate session key: /var/opt/isc/isc-bind/run/named/session.key
>   named PID file:       /var/opt/isc/isc-bind/run/named/named.pid
>   named lock file:      /var/opt/isc/isc-bind/run/named/named.lock
> 
> 
> 
> [root@srv07 log]# ldd /opt/isc/isc-bind/root/usr/sbin/named
> linux-vdso.so.1 =>  (0x00007ffcc594a000)
> libns.so.1602 => /opt/isc/isc-bind/root/usr/lib64/libns.so.1602 (0x00007f8aa0acf000)
> libdns.so.1602 => /opt/isc/isc-bind/root/usr/lib64/libdns.so.1602 (0x00007f8aa06a6000)
> libbind9.so.1600 => /opt/isc/isc-bind/root/usr/lib64/libbind9.so.1600 (0x00007f8aa0493000)
> libisccfg.so.1600 => /opt/isc/isc-bind/root/usr/lib64/libisccfg.so.1600 (0x00007f8aa0261000)
> libgssapi_krb5.so.2 => /lib64/libgssapi_krb5.so.2 (0x00007f8aa0014000)
> libkrb5.so.3 => /lib64/libkrb5.so.3 (0x00007f8a9fd2b000)
> libk5crypto.so.3 => /lib64/libk5crypto.so.3 (0x00007f8a9faf8000)
> libcom_err.so.2 => /lib64/libcom_err.so.2 (0x00007f8a9f8f4000)
> libisccc.so.1600 => /opt/isc/isc-bind/root/usr/lib64/libisccc.so.1600 (0x00007f8a9f6ea000)
> libisc.so.1602 => /opt/isc/isc-bind/root/usr/lib64/libisc.so.1602 (0x00007f8a9f475000)
> libcrypto.so.10 => /lib64/libcrypto.so.10 (0x00007f8a9f012000)
> libjson-c.so.2 => /lib64/libjson-c.so.2 (0x00007f8a9ee07000)
> libxml2.so.2 => /lib64/libxml2.so.2 (0x00007f8a9ea9d000)
> libz.so.1 => /lib64/libz.so.1 (0x00007f8a9e887000)
> libcap.so.2 => /lib64/libcap.so.2 (0x00007f8a9e682000)
> libprotobuf-c.so.1 => /opt/isc/isc-bind/root/usr/lib64/libprotobuf-c.so.1 (0x00007f8a9e479000)
> libfstrm.so.0 => /opt/isc/isc-bind/root/usr/lib64/libfstrm.so.0 (0x00007f8a9e26e000)
> libuv.so.1 => /opt/isc/isc-bind/root/usr/lib64/libuv.so.1 (0x00007f8a9e03f000)
> librt.so.1 => /lib64/librt.so.1 (0x00007f8a9de37000)
> libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f8a9dc1b000)
> libnsl.so.1 => /lib64/libnsl.so.1 (0x00007f8a9da01000)
> libdl.so.2 => /lib64/libdl.so.2 (0x00007f8a9d7fd000)
> libc.so.6 => /lib64/libc.so.6 (0x00007f8a9d42f000)
> /lib64/ld-linux-x86-64.so.2 (0x00007f8aa0d16000)
> libkrb5support.so.0 => /lib64/libkrb5support.so.0 (0x00007f8a9d21f000)
> libkeyutils.so.1 => /lib64/libkeyutils.so.1 (0x00007f8a9d01b000)
> libresolv.so.2 => /lib64/libresolv.so.2 (0x00007f8a9ce02000)
> liblzma.so.5 => /lib64/liblzma.so.5 (0x00007f8a9cbdc000)
> libm.so.6 => /lib64/libm.so.6 (0x00007f8a9c8da000)
> libattr.so.1 => /lib64/libattr.so.1 (0x00007f8a9c6d5000)
> libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f8a9c4ae000)
> libpcre.so.1 => /lib64/libpcre.so.1 (0x00007f8a9c24c000)

The reporter is using our packages:

We've installed bind directly from your CentOS repo; Do you still want us to send your debug symbols?

and the coredumps have been uploaded to my .