Re: Crashes in CentOS 7 (Apache Users)

Hi Bruno,

2017-07-20 16:33 GMT+02:00 Bruno Dorchain <bruno.dorchain@xxxxxxxxx>:

We got the following crash when under load:
*** Error in `/usr/sbin/httpd': double free or corruption (!prev): 0x00007f19a010cf80 ***
======= Backtrace: =========
/lib64/libc.so.6(+0x7c503)[0x7f19ce15c503]
/lib64/libapr-1.so.0(apr_pool_destroy+0x1a7)[0x7f19ce8da2d7]
/lib64/libapr-1.so.0(apr_pool_destroy+0x55)[0x7f19ce8da185]
/etc/httpd/modules/mod_ssl.so(+0x164d0)[0x7f19c89844d0]
/etc/httpd/modules/mod_ssl.so(+0x1307a)[0x7f19c898107a]
/usr/sbin/httpd(ap_process_request_after_handler+0x5d)[0x7f19cfc3766d]
/usr/sbin/httpd(ap_process_request+0x14)[0x7f19cfc382e4]
/usr/sbin/httpd(+0x52c32)[0x7f19cfc34c32]
/usr/sbin/httpd(ap_run_process_connection+0x40)[0x7f19cfc2cc90]
/etc/httpd/modules/mod_mpm_event.so(+0x6bf5)[0x7f19cc9f1bf5]
/lib64/libpthread.so.0(+0x7dc5)[0x7f19ce6acdc5]
/lib64/libc.so.6(clone+0x6d)[0x7f19ce1d776d]

May be linked to "ModSecurity: collection_retrieve_ex: Failed deleting collection (name ..." appearing on a regular basis.

Any hint to troubleshoot that?

I would start from https://httpd.apache.org/dev/debugging.html#crashes and see if you can get more detail from the stack-traces. Are you running a recent version of httpd / mod-security (which is not maintained by the httpd dev community, it is a third party product) ?

It would be also great if you could find how to reproduce this issue (maybe checking the requests logged around the time of the crashes, etc..).

Hope that helps!

Luca