Re: [Qemu-devel] [PATCH] Fix crash with illegal "-net nic, model=xxx" option

["Andreas Färber" <afaerber@suse.de>]

Am 12.04.2015 um 13:14 schrieb Michael S. Tsirkin:
> On Thu, Apr 09, 2015 at 03:48:57PM +0100, Peter Maydell wrote:
>> On 9 April 2015 at 14:37, Michael S. Tsirkin <mst@redhat.com> wrote:
>>> On Thu, Apr 09, 2015 at 03:32:45PM +0200, Thomas Huth wrote:
>>>> Current QEMU crashes when specifying an illegal model with the
>>>> "-net nic,model=xxx" option, e.g.:
>>>>
>>>>  $ qemu-system-x86_64 -net nic,model=n/a
>>>>  qemu-system-x86_64: Unsupported NIC model: n/a
>>>>
>>>>  Program received signal SIGSEGV, Segmentation fault.
>>>>
>>>> The gdb backtrace looks like this:
>>>>
>>>> 0x0000555555965fe0 in error_get_pretty (err=0x0) at util/error.c:152
>>>> 152       return err->msg;
>>>> (gdb) bt
>>>>  0  0x0000555555965fe0 in error_get_pretty (err=0x0) at util/error.c:152
>>>>  1  0x0000555555965ffd in error_report_err (err=0x0) at util/error.c:157
>>>>  2  0x0000555555809c90 in pci_nic_init_nofail (nd=0x555555e49860 <nd_table>, rootbus=0x5555564409b0,
>>>>     default_model=0x55555598c37b "e1000", default_devaddr=0x0) at hw/pci/pci.c:1663
>>>>  3  0x0000555555691e42 in pc_nic_init (isa_bus=0x555556f71900, pci_bus=0x5555564409b0)
>>>>     at hw/i386/pc.c:1506
>>>>  4  0x000055555569396b in pc_init1 (machine=0x5555562abbf0, pci_enabled=1, kvmclock_enabled=1)
>>>>     at hw/i386/pc_piix.c:248
>>>>  5  0x0000555555693d27 in pc_init_pci (machine=0x5555562abbf0) at hw/i386/pc_piix.c:310
>>>>  6  0x000055555572ddf5 in main (argc=3, argv=0x7fffffffe018, envp=0x7fffffffe038) at vl.c:4226
>>>>
>>>> The problem is that pci_nic_init_nofail() does not check whether the err
>>>> parameter from pci_nic_init has been set up and thus passes a NULL pointer
>>>> to error_report_err(). Fix it by correctly checking the err parameter.
>>>>
>>>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>>>
>>> Thanks!
>>> Given that this is a legacy -net option, I'm inclined
>>> to fix it post-2.3, and Cc stable.
>>> Unfortunately I won't be able to do a pull request before rc3.
>>
>> Since this is a pretty safe and simple change I'm happy to apply
>> it direct to master if you like. Do you want to provide a reviewed-by
>> tag?
> 
> I reviewed the patch, and sent a tag.
> I'm fine with you making the decision on whether it's
> appropriate for 2.3.

Hope you added a "pci:" topic? :)

Andreas

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