On Thu, Jun 13, 2019 at 11:34:06PM +0200, Philippe Mathieu-Daudé wrote:
> Commit 14e714900f6 refactored the call to spapr_dt_drc(),
> introducing a potential NULL pointer dereference while
> accessing bus->parent_dev.
> A trivial audit show 'bus' is not null in the two places
> the static function spapr_dt_drc() is called.
>
> Since the 'bus' parameter is not NULL in both callers, remove
> remove the test on if (bus), and add an assert() to silent
> static analyzers.
>
> This fixes:
>
> /hw/ppc/spapr_pci.c: 1367 in spapr_dt_pci_bus()
> >>> CID 1401933: Null pointer dereferences (FORWARD_NULL)
> >>> Dereferencing null pointer "bus".
> 1367 ret = spapr_dt_drc(fdt, offset, OBJECT(bus->parent_dev),
> 1368 SPAPR_DR_CONNECTOR_TYPE_PCI);
>
> Fixes: 14e714900f6
> Reported-by: Coverity (CID 1401933)
> Suggested-by: Greg Kurz <groug@kaod.org>
> Suggested-by: David Gibson <david@gibson.dropbear.id.au>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Applied, thanks.
> ---
> hw/ppc/spapr_pci.c | 11 +++++------
> 1 file changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
> index 957ae88bbd..fbeb1c90ee 100644
> --- a/hw/ppc/spapr_pci.c
> +++ b/hw/ppc/spapr_pci.c
> @@ -1356,12 +1356,11 @@ static int spapr_dt_pci_bus(SpaprPhbState *sphb, PCIBus *bus,
> _FDT(fdt_setprop_cell(fdt, offset, "#size-cells",
> RESOURCE_CELLS_SIZE));
>
> - if (bus) {
> - pci_for_each_device_reverse(bus, pci_bus_num(bus),
> - spapr_dt_pci_device_cb, &cbinfo);
> - if (cbinfo.err) {
> - return cbinfo.err;
> - }
> + assert(bus);
> + pci_for_each_device_reverse(bus, pci_bus_num(bus),
> + spapr_dt_pci_device_cb, &cbinfo);
> + if (cbinfo.err) {
> + return cbinfo.err;
> }
>
> ret = spapr_dt_drc(fdt, offset, OBJECT(bus->parent_dev),
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson