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Re: Curl segfault in curl_multi_perform

From: Richard W.M. Jones via curl-library <curl-library_at_lists.haxx.se>
Date: Mon, 31 Jul 2023 12:59:21 +0100

On Mon, Jul 31, 2023 at 01:38:46PM +0200, Stefan Eissing wrote:
> Rich,
>
> thanks for the testing and adding more debug output. I added test cases here to try to reproduce your scenario in curl parallel transfers with an Apache, but everything works fine here so far.
>
> What would be helpful in analysing is the Connection and Transfer ID we introduced in curl 8.2. If you add those to your debug output/crash dump, it it easier to see which transfer is affected and what it had been doing before. For an example to get these IDs, please see:
>
> https://github.com/curl/curl/blob/92ac5a8d594e766bc878ae4ad6651b9a4a98954e/src/tool_cb_dbg.c#L122

Yes, this looks like useful information in general. I'll see if I can
add this to the debug output.

BTW in the previous message I said you needed a large (10G) file.
In fact you don't need that, just any file bigger than 16K.

Rich.

> Hope this helps,
> Stefan
>
> > Am 31.07.2023 um 13:29 schrieb Richard W.M. Jones via curl-library <curl-library_at_lists.haxx.se>:
> >
> > I enabled the debug build of curl to get some more information. I
> > also added some of my own debug messages to show when the
> > H2_STREAM_LCTX macro sets or clears the stream pointer. This is all
> > with the latest curl (git commit 92ac5a8d594).
> >
> > http://oirase.annexia.org/tmp/no-stream-debug.txt
> >
> > There's now a GOAWAY message sent by my server (which I didn't see in
> > the previous output), just before the crash.
> >
> > The stack trace of the crash from this build is the same as before.
> >
> > I'm not any closer to understanding what's going on here, but still
> > looking ... If you have any suggestions for what to try, I can do that.
> >
> > Rich.
> >
> > --
> > Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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Received on 2023-07-31