Re: [Qemu-devel] [PATCH] pc-dimm: fix crash when invalid slot number is used

[Pankaj Gupta <pagupta@redhat.com>]

> QEMU will crash with:
>   Segmentation fault (core dumped)
> when negative slot number is used, ex:
>   qemu-system-x86_64 -m 1G,maxmem=20G,slots=256 \
>       -object memory-backend-ram,id=mem1,size=1G \
>       -device pc-dimm,id=dimm1,memdev=mem1,slot=-2
> 
> fix it by checking that slot number is within valid range.
> 
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> ---
>  hw/mem/pc-dimm.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
> index b1239fd0d3..29c785799c 100644
> --- a/hw/mem/pc-dimm.c
> +++ b/hw/mem/pc-dimm.c
> @@ -38,6 +38,13 @@ void pc_dimm_pre_plug(PCDIMMDevice *dimm, MachineState
> *machine,
>  
>      slot = object_property_get_int(OBJECT(dimm), PC_DIMM_SLOT_PROP,
>                                     &error_abort);
> +    if ((slot < 0 || slot >= machine->ram_slots) &&
> +         slot != PC_DIMM_UNASSIGNED_SLOT) {
> +        error_setg(&local_err, "invalid slot number, valid range is [0-%"
> +                   PRIu64 "]", machine->ram_slots - 1);
> +        goto out;
> +    }
> +
>      slot = pc_dimm_get_free_slot(slot == PC_DIMM_UNASSIGNED_SLOT ? NULL :
>      &slot,
>                                   machine->ram_slots, &local_err);
>      if (local_err) {
> --

Reviewed-by: Pankaj Gupta <pagupta@redhat.com>

> 2.18.1
> 
> 
>