Re: [Qemu-devel] [PATCH v3 08/38] 9pfs: Fix CLI parsing crash on error

[Eric Blake]

On 10/17/18 2:15 AM, Greg Kurz wrote:
> On Tue, 16 Oct 2018 19:41:28 +0200
> Markus Armbruster <address@hidden> wrote:
>
> > Calling error_report() in a function that takes an Error ** argument
> > is suspicious.  9p-handle.c's handle_parse_opts() does that, and then
> > fails without setting an error.  Wrong.  Its caller crashes when it
> > tries to report the error:
> >
> >      $ qemu-system-x86_64 -nodefaults -fsdev id=foo,fsdriver=handle
> >      qemu-system-x86_64: -fsdev id=foo,fsdriver=handle: warning: handle backend 
> > is deprecated
> >      qemu-system-x86_64: -fsdev id=foo,fsdriver=handle: fsdev: No path specified
> >      Segmentation fault (core dumped)
> >
> > Screwed up when commit 91cda4e8f37 (v2.12.0) converted the function to
> > Error.  Fix by calling error_setg() instead of error_report().
> >
> > Fixes: 91cda4e8f372602795e3a2f4bd2e3adaf9f82255
> > Cc: Greg Kurz <address@hidden>
> > Signed-off-by: Markus Armbruster <address@hidden>
> > Acked-by: Greg Kurz <address@hidden>
> > ---
>
> Hi Markus,
>
> FWIW you had a Reviewed-by from Eric.
>
> https://lists.nongnu.org/archive/html/qemu-devel/2018-10/msg03297.html

Most likely crossed mail. Although I composed my v2 review Monday, an 
ISP outage prevented it from hitting the list until Tuesday after Markus 
had prepared v3. (And the fact that a small fire near Dallas was able to 
take out internet access for more than a million AT&T customers for more 
than 12 hours makes you appreciate how much we really rely on the 
Internet in modern society)

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org