segfaults on version 1.10.1 / 1.8.1

[Altegras]

Hello,

It compiles without any issues on 1.10.1 or 1.8.1 but soon as I restart nginx with directive rdns on; in http context:

[5020508.218404] nginx[8250]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020511.382247] nginx[8249]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020513.467525] nginx[8258]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020514.108250] nginx[8251]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020514.532005] nginx[8259]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020516.587455] nginx[5585]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020517.208997] nginx[8261]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020517.949545] nginx[8262]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020519.417238] nginx[8260]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020519.496210] nginx[8263]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020519.768009] nginx[8265]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020519.833654] nginx[8246]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020519.891389] nginx[5570]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]
[5020521.415321] nginx[8268]: segfault at 20 ip 0000000000412420 sp 00007ffca8e4f8e0 error 4 in nginx[400000+ab000]

With [rdns off;] = no segfaults and the page loads properly, tried to put rdns on in http OR server OR location context, same effect.

uname -r

3.16.0-4-amd64

gcc --version

gcc (Debian 4.9.2-10) 4.9.2
Copyright (C) 2014 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

ldd --version

ldd (Debian GLIBC 2.19-18+deb8u4) 2.19
Copyright (C) 2014 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
Written by Roland McGrath and Ulrich Drepper.

Deb 8

[distorhead]

worker_processes  1;

events {
    worker_connections 1024;
}

http {
    log_format main '$remote_addr - $remote_user [$time_local] "$request" '
                    '$status $body_bytes_sent "$http_referer" '
                    '"$http_user_agent" "$http_x_forwarded_for" "$rdns_hostname"';

    access_log logs/access.log main;

    include mime.types;
    default_type application/octet-stream;
    sendfile on;
    keepalive_timeout 65;

    resolver 127.0.0.1;
    rdns on;

    server {
        listen 8082;
        server_name localhost;

        location / {
            root html;
            index index.html index.htm;
        }
    }
}

Tried this config without catching segfault on 1.8.1 and 1.10.1.
Need more of your nginx.conf.

[Altegras]

Check this:

server {
        listen 8082;
        server_name localhost;

        location / {
            if ($rdns_hostname ~* (google\.com$|googlebot\.com$|search\.msn\.com$|crawl\.yahoo\.net$) 
            { /* some work */ }

            root html;
            index index.html index.htm;
        }
    }

[distorhead]

Still cannot reproduce.
I build pure nginx source with only one external module. Maybe there is some problem related to work in conjunction with some other modules.

[suedadam]

I'm getting this as well when my config is similar to:

if ($rdns_hostname ~* (.*\.duckduckgo\.com|.*\.googlebot\.com|.*\.crawl\.yahoo\.net|.*\.search\.msn\.com|.*\.crawl\.baidu.com))$
    <work here>
}

[suedadam]

Getting this on version 1.11.6

[revilzs]

Getting the same problem with version 1.10.3 and a similar config.