Hi,
This time h2s = 0x30 ;)
it crashed here:
void testcorrupt(void *ptr)
{
[...]
if (h2s->cs != cs)
return;
[...]
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x0000556b617f0562 in testcorrupt (ptr=0x7f99741d85a0) at
src/mux_h2.c:6228
6228 src/mux_h2.c: No such file or directory.
[Current thread is 1 (Thread 0x7f99a484d700 (LWP 28658))]
(gdb) bt full
#0 0x0000556b617f0562 in testcorrupt (ptr=0x7f99741d85a0) at
src/mux_h2.c:6228
cs = 0x7f99741d85a0
h2s = 0x30
#1 0x0000556b61850b1a in process_stream (t=0x7f99741d8c60,
context=0x7f99682cd7b0, state=1284) at src/stream.c:2147
srv = 0x556b622770e0
s = 0x7f99682cd7b0
sess = 0x7f9998057170
rqf_last = 9469954
rpf_last = 2151677952
rq_prod_last = 8
rq_cons_last = 0
rp_cons_last = 8
rp_prod_last = 0
req_ana_back = 0
req = 0x7f99682cd7c0
res = 0x7f99682cd820
si_f = 0x7f99682cdae8
si_b = 0x7f99682cdb40
rate = 1
#2 0x0000556b61962a5f in run_tasks_from_list (list=0x556b61db1600
<task_per_thread+832>, max=150) at src/task.c:371
process = 0x556b6184d8e6 <process_stream>
t = 0x7f99741d8c60
state = 1284
ctx = 0x7f99682cd7b0
done = 2
[...]
pt., 6 lis 2020 o 20:00 Willy Tarreau <[email protected]> napisał(a):
> Maciej,
>
> I wrote this ugly patch to try to crash as soon as possible when a corrupt
> h2s->subs is detected. The patch was written for 2.2. I only instrumented
> roughly 30 places in process_stream() which is a fairly likely candidate.
> I just hope it happens within the context of the stream itself otherwise
> it will become really painful.
>
> You can apply this patch on top of your existing changes. It will try to
> detect the presence of a non-zero lowest bit in the subs pointer (which
> should never happen). If we're lucky it will crash inside process_stream()
> between two points and we'll be able to narrow it down. If we're unlucky
> it will crash when entering it and that will not be fun.
>
> If you want to play with it, you can apply TEST_SI() on stream_interface
> pointers (often called "si"), TEST_STRM() on stream pointers, and TEST_CS()
> on conn_stream pointers (often called "cs").
>
> Please just let me know how it goes. Note, I tested it, it passes all
> regtests for me so I'm reasonably confident it should not crash by
> accident. But I can't be sure, I'm just using heuristics, so please do
> not put it in sensitive production!
>
> Thanks,
> Willy
>
