Re: [Qemu-devel] [PATCH] qemu_opts_parse(): always check return value

[Markus Armbruster <armbru@redhat.com>]

Laszlo Ersek <lersek@redhat.com> writes:

> qemu_opts_parse() can always return NULL, even if the QemuOptsList.desc in
> question would be trivial to satisfy (eg. because it's empty). For
> example:
>
> qemu_opts_parse()
>   opts_parse()
>     qemu_opts_create()
>       id_wellformed()
>
> In practice:
>
>   $ .../qemu-system-x86_64 -acpitable id=3
>   qemu-system-x86_64: -acpitable id=3: Parameter 'id' expects an identifier
>   **
>   ERROR:vl.c:3491:main: assertion failed: (opts != NULL)
>   Aborted (core dumped)
>
>   $ .../qemu-system-x86_64 -smbios id=3
>   qemu-system-x86_64: -smbios id=3: Parameter 'id' expects an identifier
>   Segmentation fault (core dumped)
>
> I checked all qemu_opts_parse() invocations (and all drive_def()
> invocations too, because it blindly forwards the former's retval). Only
> the two above examples look problematic.
>
> Signed-off-by: Laszlo Ersek <lersek@redhat.com>

Your fix is fine.  I didn't redo your search for other unsafe uses.

Reviewed-by: Markus Armbruster <armbru@redhat.com>