Re: nginx core dump issue

[Andrei Belov]

On 21 Oct 2014, at 00:54, i_way <nginx-forum at nginx.us> wrote:

> Hi expert,
> 
> I am running into nginx core dump issue and I need expert's help.
> Thank you so much!
> 
> We are running nginx 1.6.0 + mod_security on RHEL 6.4.
> We are using the two ports with https.
> 
> ■core dump
> GNU gdb (GDB) Red Hat Enterprise Linux (7.2-60.el6_4.1)
> Copyright (C) 2010 Free Software Foundation, Inc.
> License GPLv3+: GNU GPL version 3 or later
> <http://gnu.org/licenses/gpl.html>
> This is free software: you are free to change and redistribute it.
> There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
> and "show warranty" for details.
> This GDB was configured as "x86_64-redhat-linux-gnu".
> For bug reporting instructions, please see:
> <http://www.gnu.org/software/gdb/bugs/>...
> Reading symbols from /usr/sbin/nginx.debug...done.
> 
> warning: core file may not match specified executable file.
> [New Thread 28081]
> Missing separate debuginfo for
> Try: yum --disablerepo='*' --enablerepo='*-debug*' install
> /usr/lib/debug/.build-id/a6/993d9af0d108bfc4a2bbfdb176ea3288f6fd5c
> #0  ngx_http_chunked_body_filter (r=0x1811350, in=<value optimized out>) at
> src/http/modules/ngx_http_chunked_filter_module.c:126
> 126             size += ngx_buf_size(cl->buf);
> Missing separate debuginfos, use: debuginfo-install apr-1.3.9-5.el6_2.x86_64
> apr-util-1.3.9-3.el6_0.1.x86_64 cyrus-sasl-lib-2.1.23-13.el6_3.1.x86_64
> db4-4.7.25-17.el6.x86_64 db4-4.7.25-18.el6_4.x86_64
> expat-2.0.1-11.el6_2.x86_64 glibc-2.12-1.107.el6.x86_64
> glibc-2.12-1.132.el6.x86_64 keyutils-libs-1.4-4.el6.x86_64
> krb5-libs-1.10.3-10.el6.x86_64 krb5-libs-1.10.3-10.el6_4.6.x86_64
> libcom_err-1.41.12-14.el6.x86_64 libcom_err-1.41.12-18.el6.x86_64
> libcurl-7.19.7-35.el6.x86_64 libcurl-7.19.7-37.el6_4.x86_64
> libidn-1.18-2.el6.x86_64 libselinux-2.0.94-5.3.el6.x86_64
> libselinux-2.0.94-5.3.el6_4.1.x86_64 libssh2-1.4.2-1.el6.x86_64
> libuuid-2.17.2-12.14.el6.x86_64 libxml2-2.7.6-14.el6.x86_64
> libxml2-2.7.6-8.el6_3.4.x86_64 nspr-4.10.2-1.el6_5.x86_64
> nspr-4.9.2-1.el6.x86_64 nss-3.14.0.0-12.el6.x86_64 nss-3.15.3-3.el6_5.x86_64
> nss-softokn-freebl-3.12.9-11.el6.x86_64
> nss-softokn-freebl-3.14.3-9.el6.x86_64 nss-util-3.14.0.0-2.el6.x86_64
> nss-util-3.15.3-1.el6_5.x86_64 openldap-2.4.23-32.el6_4.1.x86_64
> openssl-1.0.0-27.el6.x86_64 openssl-1.0.1e-16.el6_5.1.x86_64
> pcre-7.8-6.el6.x86_64 zlib-1.2.3-29.el6.x86_64
> (gdb) bt
> #0  ngx_http_chunked_body_filter (r=0x1811350, in=<value optimized out>) at
> src/http/modules/ngx_http_chunked_filter_module.c:126
> #1  0x0000000000463114 in ngx_http_gzip_body_filter (r=0x1811350,
> in=0x2171b38) at src/http/modules/ngx_http_gzip_filter_module.c:325
> #2  0x00000000004665cc in ngx_http_ssi_body_filter (r=<value optimized out>,
> in=<value optimized out>) at
> src/http/modules/ngx_http_ssi_filter_module.c:444
> #3  0x0000000000469c73 in ngx_http_charset_body_filter (r=0x1811350,
> in=<value optimized out>) at
> src/http/modules/ngx_http_charset_filter_module.c:643
> #4  0x000000000046b5cf in ngx_http_addition_body_filter (r=0x1811350,
> in=0x2171b38) at src/http/modules/ngx_http_addition_filter_module.c:166
> #5  0x000000000046be2c in ngx_http_gunzip_body_filter (r=0x1811350,
> in=0x2171b38) at src/http/modules/ngx_http_gunzip_filter_module.c:184
> #6  0x000000000049b83e in ngx_http_modsecurity_body_filter (r=<value
> optimized out>, in=<value optimized out>)
>    at
> /home/odnsys777/rpmbuild/BUILD/nginx-1.6.0/modsecurity-2.8.0/nginx/modsecurity/ngx_http_modsecurity.c:1209
> #7  0x000000000040fd81 in ngx_output_chain (ctx=0x21717c0,
> in=0x7fff6190f850) at src/core/ngx_output_chain.c:66
> #8  0x0000000000449f25 in ngx_http_copy_filter (r=0x1811350,
> in=0x7fff6190f850) at src/http/ngx_http_copy_filter_module.c:143
> #9  0x000000000045d686 in ngx_http_range_body_filter (r=0x1811350,
> in=0x7fff6190f850) at src/http/modules/ngx_http_range_filter_module.c:594
> #10 0x000000000043b0b5 in ngx_http_output_filter (r=0x1811350,
> in=0x7fff6190f850) at src/http/ngx_http_core_module.c:1964
> #11 0x00000000004410fd in ngx_http_send_special (r=0x1811350, flags=<value
> optimized out>) at src/http/ngx_http_request.c:3332
> #12 0x0000000000454a9d in ngx_http_upstream_finalize_request (r=0x1811350,
> u=0x2127ee0, rc=0) at src/http/ngx_http_upstream.c:3551
> #13 0x000000000045551d in ngx_http_upstream_process_request (r=0x1811350) at
> src/http/ngx_http_upstream.c:3159
> #14 0x0000000000459e69 in ngx_http_upstream_send_response (r=0x1811350,
> u=0x2127ee0) at src/http/ngx_http_upstream.c:2493
> #15 ngx_http_upstream_process_header (r=0x1811350, u=0x2127ee0) at
> src/http/ngx_http_upstream.c:1735
> #16 0x000000000045517d in ngx_http_upstream_handler (ev=0x2139a38) at
> src/http/ngx_http_upstream.c:977
> #17 0x0000000000425194 in ngx_event_process_posted (cycle=0x1804f80,
> posted=0x76ed40) at src/event/ngx_event_posted.c:40
> #18 0x000000000042c2b5 in ngx_worker_process_cycle (cycle=0x1804f80,
> data=<value optimized out>) at src/os/unix/ngx_process_cycle.c:816
> #19 0x000000000042a784 in ngx_spawn_process (cycle=0x1804f80, proc=0x42c1e0
> <ngx_worker_process_cycle>, data=0x1, name=0x4e5356 "worker process",
> respawn=-3)
>    at src/os/unix/ngx_process.c:198
> #20 0x000000000042c44c in ngx_start_worker_processes (cycle=0x1804f80, n=4,
> type=-3) at src/os/unix/ngx_process_cycle.c:364
> #21 0x000000000042cc74 in ngx_master_process_cycle (cycle=0x1804f80) at
> src/os/unix/ngx_process_cycle.c:136
> #22 0x000000000040c4c6 in main (argc=<value optimized out>, argv=<value
> optimized out>) at src/core/nginx.c:407
> (gdb)

You can try to use the “nginx_refactoring” branch from here:
https://github.com/SpiderLabs/ModSecurity/tree/nginx_refactoring

or from here:
https://github.com/defanator/ModSecurity/tree/nginx_refactoring

There was a number of issues affecting nginx, fixed in those branches.

Hope this helps.