<div dir="ltr"><div><div>Well, it turns out that the git version of mosh works perfectly, so I have no idea what would be causing the problem. If you'd like, I can modify the 1.2.5-r1 sources to get the coredump, but I don't think it'll be of much use to any of us, since the problem is fixed on both ends.<br><br></div>Thanks,<br></div>Deven<br></div><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Jun 7, 2016 at 8:52 PM, John Hood <span dir="ltr"><<a href="mailto:cgull@glup.org" target="_blank">cgull@glup.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF">
<p>Oops, I'm forgetting two rather important things, sorry.</p>
<p>* The --local flag is only in mosh master, not yet in any release
(though 1.2.6 is coming soon). Available on GitHub near you. If
you don't want to mess with source you can run mosh-client and
mosh-server manually as documented on
<a href="https://mosh.mit.edu/" target="_blank"><https://mosh.mit.edu/></a>.<br>
</p>
<p>* mosh-server itself disables coredumps to protect its
cryptographic secrets. Disabling that requires editing source and
rebuilding mosh-server.</p>
<p>regards,</p>
<p> --jh<br>
</p><div><div class="h5">
<div>On 06/07/2016 20:21, Deven Lahoti
wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">mosh --local just gives "unknown option", and I
can't figure out how to enable coredumps for mosh-server -
coredumps work for everything else, so I'm not sure why they're
disabled here.<br>
</div>
<div class="gmail_extra"><br>
<div class="gmail_quote">On Tue, Jun 7, 2016 at 9:39 AM, John
Hood <span dir="ltr"><<a href="mailto:cgull@glup.org" target="_blank">cgull@glup.org</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="auto">
<div>Try running </div>
<div><br>
</div>
<div>strace -ffo trace mosh --local 127.0.0.1</div>
<div><br>
</div>
<div>on that server after enabling coredumps. That's not
exactly the same as normal execution, since it doesn't
use ssh, but it's useful for issues like this one.</div>
<div><br>
</div>
<div>regards,</div>
<div><br>
</div>
<div> --jh</div>
<div>
<div>
<div><br>
On Jun 7, 2016, at 12:56 AM, Deven Lahoti <<a href="mailto:deywos@mit.edu" target="_blank"></a><a href="mailto:deywos@mit.edu" target="_blank">deywos@mit.edu</a>>
wrote:<br>
<br>
</div>
<blockquote type="cite">
<div>
<p dir="ltr">Neither strace nor gdb will give me a
backtrace, since they both lose track of it when
it forks, but the failure happens after forking.
For some reason, systemd says that coredumps are
disabled for the process, so I can't get one of
those either. </p>
<div class="gmail_quote">On Jun 7, 2016 00:31,
"Alex Chernyakhovsky" <<a href="mailto:achernya@mit.edu" target="_blank"></a><a href="mailto:achernya@mit.edu" target="_blank">achernya@mit.edu</a>>
wrote:<br type="attribution">
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Unfortunately, that's
not much to go on. Could you grab the core
file<br>
and get a backtrace? I'm assuming some syscall
(probably malloc?)<br>
failed.<br>
<br>
Sincerely,<br>
-Alex<br>
<br>
On Tue, Jun 7, 2016 at 12:18 AM, Deven Lahoti
<<a href="mailto:deywos@mit.edu" target="_blank">deywos@mit.edu</a>>
wrote:<br>
> I don't think that's the problem, since
it's now giving me:<br>
> mosh-server[21489]: segfault at 0 ip
(null) sp 00007fffffffcbd8<br>
> error 14 in
mosh-server[555555554000+60000]<br>
><br>
> On Mon, Jun 6, 2016 at 11:42 PM, Alex
Chernyakhovsky <<a href="mailto:achernya@mit.edu" target="_blank">achernya@mit.edu</a>><br>
> wrote:<br>
>><br>
>> I think the offending line is<br>
>><br>
>> Jun 06 22:32:19 <hostname>
kernel: PAX: From 18.X.X.X: execution<br>
>> attempt in: (null), 00000000-00000000
00000000<br>
>> Jun 06 22:32:19 <hostname>
kernel: PAX: terminating task:<br>
>>
/usr/bin/mosh-server(mosh-server):12505,
uid/euid: XXXX/XXXX, PC:<br>
>> (nil), SP: 000003844385a508<br>
>><br>
>> mosh-server needs to fork and exec to
start subprocesses, and your<br>
>> kernel/configuration doesn't consider
mosh-server to be in the<br>
>> whitelist.<br>
>><br>
>> Sincerely,<br>
>> -Alex<br>
>><br>
>><br>
>> On Mon, Jun 6, 2016 at 11:30 PM,
Deven Lahoti <<a href="mailto:deywos@mit.edu" target="_blank">deywos@mit.edu</a>>
wrote:<br>
>> > Hi, when trying to connect to my
machine running Gentoo Hardened on<br>
>> > kernel<br>
>> > 4.4.8, mosh-server fails to
start. Here are the logs (modified to remove<br>
>> > personal info) [<a href="http://web.mit.edu/deywos/www/mosh.log" rel="noreferrer" target="_blank"></a><a href="http://web.mit.edu/deywos/www/mosh.log" target="_blank">http://web.mit.edu/deywos/www/mosh.log</a>].
I'm not really<br>
>> > sure<br>
>> > what the problem is, and I don't
know much about how mosh works, so I<br>
>> > was<br>
>> > hoping someone here could help
me out.<br>
>> ><br>
>> > Thanks,<br>
>> > Deven<br>
>> ><br>
>> >
_______________________________________________<br>
>> > mosh-users mailing list<br>
>> > <a href="mailto:mosh-users@mit.edu" target="_blank">mosh-users@mit.edu</a><br>
>> > <a href="http://mailman.mit.edu/mailman/listinfo/mosh-users" rel="noreferrer" target="_blank">http://mailman.mit.edu/mailman/listinfo/mosh-users</a><br>
>> ><br>
><br>
><br>
</blockquote>
</div>
</div>
</blockquote>
<blockquote type="cite">
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