Re: [PULL 0/5] 9p queue 2022-02-10

[Peter Maydell]

On Mon, 14 Feb 2022 at 09:47, Christian Schoenebeck
<qemu_oss@crudebyte.com> wrote:
> So this is about the 'dirent' patch:
> https://github.com/cschoenebeck/qemu/commit/de19c79dad6a2cad54ae04ce754d47c07bf9bc93
>
> In conjunction with the 9p fuzzing tests:
> https://wiki.qemu.org/Documentation/9p#Fuzzing
>
> I first thought it might be a false positive due to the unorthodox handling of
> dirent duplication by that patch, but from the ASan output below I am not
> really sure about that.
>
> Is there a way to get the content of local variables?

Yes. You can build locally with the clang sanitizers enabled and then
run under gdb and with the appropriate environment variables to tell the
sanitizer to abort() on failures.

> Would it be possible that the following issue (g_memdup vs. g_memdup2) might
> apply here?
> https://discourse.gnome.org/t/port-your-module-from-g-memdup-to-g-memdup2-now/5538

It seems unlikely that the problem is that you're allocating more than
4 gigabytes and thus hitting a 64-to-32 truncation.

thanks
-- PMM