Crash in libnettle6 on armhf and powerpc archs

[dobey]

Currently, in wily, some landing silos are blocked now, due to a segfault occurring when attempting to run certain test binaries, which depend on the gnutls stack. Most notably so far, I've hit this issue in projects which are using QtNetwork or libcurl for network access. The issue is a crash in libnettle6, with the following stack trace:

Program received signal SIGSEGV, Segmentation fault.
0xb6c20b00 in nettle_yarrow256_update ()
   from /usr/lib/arm-linux-gnueabihf/libnettle.so.6
(gdb) bt
#0 0xb6c20b00 in nettle_yarrow256_update ()
   from /usr/lib/arm-linux-gnueabihf/libnettle.so.6
#1 0xb6bd6406 in ?? () from /usr/lib/arm-linux-gnueabihf/libgnutls-deb0.so.28
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

There seems to also be no dbgsym package available yet on ddebs.ubuntu.com for this package, so I've not been able to get a more complete trace.

This is happening with nettle 3.1.1-3 in wily-proposed.

Link to build failure in a PPA: https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/landing-022/+build/7526566

[Adam Conrad (adconrad)]

Log in the bug description is from:

https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/landing-022/+build/7526566

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Magnus Holmgren (holmgren)]

There's nothing to fix i nettle. but other packages depending on it need to be rebuilt in order.
I don't know how Ubuntu manages library transitions like this, but you can have a look at https://release.debian.org/transitions/html/auto-nettle.html (check the "good" box).

What I find strange is that libnettle 6 is installed but not libnettle4; at least libgnutls-deb0-28 should depend on the latter. Is it already installed before the build starts?

[dobey (dobey)]

gnutls is a core part of the system, so the version in the release
pocket that is already built against libnettle4 is already installed in
the base image, along with libnettle4, yes. Because there isn't a newer
version of libnettle4 available, it is not being upgraded at the start.

On Wed, 2015-06-10 at 18:26 +0000, Magnus Holmgren wrote:
> There's nothing to fix i nettle. but other packages depending on it need to be rebuilt in order.
> I don't know how Ubuntu manages library transitions like this, but you can have a look at https://release.debian.org/transitions/html/auto-nettle.html (check the "good" box).
>
> What I find strange is that libnettle 6 is installed but not libnettle4;
> at least libgnutls-deb0-28 should depend on the latter. Is it already
> installed before the build starts?
>

[Adam Conrad (adconrad)]

This particular portion of the transition is done in -proposed, which allows the builds being complained about to build again. The rest of the transition is still ongoing, but there's no point keeping this bug open until it's done.