Hi All
I wonder if anybody is looking at this issue. At the moment, the build cores
even at the end of generating a Makefile.
If not, I would like to get my hands dirty in an attmpt to get the ball
rolling. Any help on how to get a handle on the "ip comparisons" recommended by
W. Rowe Jr would be much appreciated.
Regards,
Jie
* William A Rowe Jr <wr...@rowe-clan.net> wrote:
> Date: Thu, 19 May 2016 11:23:33 -0500
> From: William A Rowe Jr <wr...@rowe-clan.net>
> To: httpd <d...@httpd.apache.org>, modperl@perl.apache.org
> Subject: Re: New segfault with 2.4.20 with mod_perl
>
> Re-sending to include the correct perl.a.o dev list.
>
> On Thu, Apr 14, 2016 at 1:25 PM, William A Rowe Jr <wr...@rowe-clan.net>
> wrote:
>
> > The defect appears to be in t/protocol/TestProtocol/pseudo_http.pm...
> >
> > First, the handler is registered using
> >
> > PerlProcessConnectionHandler TestProtocol::pseudo_http
> >
> > so its activities are outside of the request handling phase.
> >
> > Note that this logic has been broken, for a long time;
> >
> > <IfVersion > 2.4.1>
> > <IfModule mod_access_compat.c>
> > Order Deny,Allow
> > Allow from @servername@
> > </IfModule>
> > </IfVersion>
> >
> > Where @servername@ is a hostname, this module defect was
> > identified in version 2.4.20 when we began using the per-req
> > hostname in comparison (based on r->useragent_addr, which
> > is obviously is null during part of the read_request phase).
> >
> > But this module using mod_access_compat during the connection
> > phase has been broken for much longer, since Allow from {ip-addr}
> > would already have failed since 2.4.1 was released, due to the
> > same null r->useragent_addr.
> >
> > Effectively, mod_access_compat.c never supported per-connection
> > IP addresses since it was added. The fact that it supported
> > per-connection hostname comparison was a quirk, and that the
> > pseudo_http tests only looked at hostname and not ip comparisons
> > was an oversight.
> >
> > But the module will fail in other manners if attempting to use
> > http request_rec processing since that record is never fleshed
> > out with the proper read/post_read request hook phases.
> >
> > My thought is to simply decouple access_compat from this
> > module test... opinions?
> >
> > See also; https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=820824;msg=5
> >
> >
> > On Thu, Apr 14, 2016 at 11:55 AM, William A Rowe Jr <wr...@rowe-clan.net>
> > wrote:
> >
> >> We can be more vigilant about unexpectedly null values, however...
> >>
> >> how are you running request processing in the connection callback
> >> of mod_perl? That makes no sense, and probably signals a deeper
> >> logic error.
> >>
> >> The access checker is configured per-dir, so until the request rec
> >> is completely initialized during read_request, this doesn't make
> >> much sense to me (full backtrace .. including frames #6-#10, for
> >> those who are curious...)
> >>
> >> Either the callback list registered for modperl_callback_connection,
> >> or the Perl_runops_standard, or the Perl_pp_entersub invoking the
> >> run_access_checker hook seem the most suspect here.
> >>
> >> #0 apr_getnameinfo (hostname=hostname@entry=0x7fd4461ee368, sockaddr=0x0,
> >> flags=flags@entry=0)
> >> at /tmp/buildd/apr-1.5.2/network_io/unix/sockaddr.c:663
> >> #1 0x000055feaf0f513a in ap_get_useragent_host (r=r@entry=0x7fd4461ee0a0,
> >> type=type@entry=3,
> >> str_is_ip=str_is_ip@entry=0x7fd44740c9c4) at core.c:990
> >> #2 0x00007fd4519d7212 in find_allowdeny (r=r@entry=0x7fd4461ee0a0,
> >> method=method@entry=0, a=<optimized out>,
> >> a=<optimized out>) at mod_access_compat.c:279
> >> #3 0x00007fd4519d74b2 in check_dir_access (r=0x7fd4461ee0a0) at
> >> mod_access_compat.c:332
> >> #4 0x000055feaf0f8f30 in ap_run_access_checker (r=r@entry=0x7fd4461ee0a0)
> >> at request.c:87
> >> #5 0x00007fd448a6f7dd in XS_Apache2__RequestRec_run_access_checker
> >> (my_perl=0x55feb2964a20, cv=<optimized out>)
> >> at HookRun.c:235
> >> #6 0x00007fd44f5f7e6a in Perl_pp_entersub () from
> >> /usr/lib/x86_64-linux-gnu/libperl.so.5.22
> >> #7 0x00007fd44f5f0ca6 in Perl_runops_standard () from
> >> /usr/lib/x86_64-linux-gnu/libperl.so.5.22
> >> #8 0x00007fd44f575f06 in Perl_call_sv () from
> >> /usr/lib/x86_64-linux-gnu/libperl.so.5.22
> >> #9 0x00007fd44f91ec28 in modperl_callback
> >> (my_perl=my_perl@entry=0x55feb2964a20, handler=0x7fd4461f2750,
> >> p=p@entry=0x7fd4461f2028, r=r@entry=0x0, s=s@entry=0x7fd453ddc628,
> >> args=0x55feb3beebd0)
> >> at modperl_callback.c:100
> >> #10 0x00007fd44f91f576 in modperl_callback_run_handlers (idx=0,
> >> type=type@entry=1, r=r@entry=0x0,
> >> c=<optimized out>, s=0x7fd453ddc628, pconf=pconf@entry=0x0, plog=0x0,
> >> ptemp=0x0, run_mode=MP_HOOK_RUN_FIRST)
> >> at modperl_callback.c:236
> >> #11 0x00007fd44f91fd4f in modperl_callback_connection (idx=<optimized
> >> out>, c=<optimized out>,
> >> run_mode=<optimized out>) at modperl_callback.c:359
> >> #12 0x000055feaf10cdf0 in ap_run_process_connection
> >> (c=c@entry=0x7fd4461f22b8) at connection.c:42
> >> #13 0x000055feaf10d340 in ap_process_connection (c=c@entry=0x7fd4461f22b8,
> >> csd=csd@entry=0x7fd4461f20a0)
> >> at connection.c:226
> >> #14 0x00007fd4523f3e6b in process_socket (bucket_alloc=0x7fd4461f0028,
> >> my_thread_num=1, my_child_num=0,
> >> sock=0x7fd4461f20a0, p=0x7fd4461f2028, thd=0x7fd453eb27a0) at
> >> worker.c:631
> >> #15 worker_thread (thd=0x7fd453eb27a0, dummy=<optimized out>) at
> >> worker.c:990
> >> #16 0x00007fd453418454 in start_thread (arg=0x7fd44740d700) at
> >> pthread_create.c:334
> >> #17 0x00007fd453155ecd in clone () at
> >> ../sysdeps/unix/sysv/linux/x86_64/clone.S:109
> >>
> >>
> >> Before we chase down a potential non-defect in httpd, any thoughts
> >> on the underlying modperl or script logic?
> >>
> >>
> >> On Thu, Apr 14, 2016 at 1:44 AM, Takashi Sato <taka...@tks.st> wrote:
> >>
> >>> r->useragent_addr is assigned on ap_read_request (http_core.c),
> >>> called from ap_process_http_(async_)connection
> >>> called from process_connection hook (APR_HOOK_REALLY_LAST).
> >>>
> >>> The SEGV occured on process_connection hook, maybe before
> >>> ap_process_http_(async_)connection,
> >>>
> >>> #11 0x00007fd44f91fd4f in modperl_callback_connection (idx=<optimized
> >>> out>, c=<optimized out>,
> >>> run_mode=<optimized out>) at modperl_callback.c:359
> >>> #12 0x000055feaf10cdf0 in ap_run_process_connection
> >>> (c=c@entry=0x7fd4461f22b8) at connection.c:42
> >>> #13 0x000055feaf10d340 in ap_process_connection
> >>> (c=c@entry=0x7fd4461f22b8, csd=csd@entry=0x7fd4461f20a0)
> >>> at connection.c:226
> >>>
> >>> so r->useragent_addr had not been assigned any value.
> >>>
> >>
> >>
> >
