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References: <20181015115309.17089-1-armbru@redhat.com>
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From: Eric Blake <eblake@redhat.com>
Message-ID: <3c9a97f7-1a86-4bc4-6127-ac05232b7a99@redhat.com>
Date: Mon, 15 Oct 2018 14:00:24 -0500
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Subject: Re: [Qemu-devel] [PATCH v2 08/35] 9pfs: Fix CLI parsing crash on
 error
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To: Markus Armbruster <armbru@redhat.com>, qemu-devel@nongnu.org
Cc: Greg Kurz <groug@kaod.org>

On 10/15/18 6:52 AM, Markus Armbruster 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 <groug@kaod.org>
> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> Acked-by: Greg Kurz <groug@kaod.org>
> ---
>   hw/9pfs/9p-handle.c | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)

Reviewed-by: Eric Blake <eblake@redhat.com>


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