Segfault in nginx 1.0.5

[Maxim Dounin]

Hello!

On Mon, Aug 08, 2011 at 01:50:12AM +0000, Kingsley Foreman wrote:

> I'm seeing a small segfault in 1.0.5
> 
> It is strage there is something triggering it as it happens at 
> the same time every night. It isn't triggered by crontab as I 
> have nothing that runs at that time.
> I'm running the keepalive patch (however this was happening 
> before I installed it).
> 
> Anyway here is the backtrace
> 
> 
> #0  0x00007fd02a58cc9e in memcpy () from /lib/libc.so.6
> #1  0x000000000049fb4c in ngx_http_proxy_create_request (r=0x19f3d80) at src/http/modules/ngx_http_proxy_module.c:1021
> #2  0x0000000000470a2b in ngx_http_upstream_init_request (r=0x19f3d80) at src/http/ngx_http_upstream.c:497
> #3  0x0000000000470868 in ngx_http_upstream_init (r=0x19f3d80) at src/http/ngx_http_upstream.c:438
> #4  0x0000000000466f5c in ngx_http_read_client_request_body (r=0x19f3d80, post_handler=0x470775 <ngx_http_upstream_init>)
>     at src/http/ngx_http_request_body.c:58
> #5  0x000000000049eb49 in ngx_http_proxy_handler (r=0x19f3d80) at src/http/modules/ngx_http_proxy_module.c:655
> #6  0x000000000044f19b in ngx_http_core_content_phase (r=0x19f3d80, ph=0x1a07a60) at src/http/ngx_http_core_module.c:1339
> #7  0x000000000044ddc4 in ngx_http_core_run_phases (r=0x19f3d80) at src/http/ngx_http_core_module.c:837
> #8  0x000000000044dd3b in ngx_http_handler (r=0x19f3d80) at src/http/ngx_http_core_module.c:820
> #9  0x000000000045159d in ngx_http_internal_redirect (r=0x19f3d80, uri=0x7fff40c440f0, args=0x7fff40c440e0)
>     at src/http/ngx_http_core_module.c:2347
> #10 0x0000000000457836 in ngx_http_send_error_page (r=0x19f3d80, err_page=0x19b3168) at src/http/ngx_http_special_response.c:560
> #11 0x0000000000457430 in ngx_http_special_response_handler (r=0x19f3d80, error=400) at src/http/ngx_http_special_response.c:402
> #12 0x000000000045c31d in ngx_http_finalize_request (r=0x19f3d80, rc=400) at src/http/ngx_http_request.c:1944
> #13 0x0000000000459bfe in ngx_http_process_request_line (rev=0x7fd029684de0) at src/http/ngx_http_request.c:907

Could you please show your config?  It looks like you are using 
something like

    error_page  400  @fallback;

    location @fallback {
        proxy_pass ...
    }

in it.

This is obviously a bug, though you may easily avoid triggering it 
by not intercepting error page 400.

Maxim Dounin