Hi Luca,
> On 11 Oct 2021, at 08:56, Luca Fancellu <luca.fance...@arm.com> wrote:
>
> Fix for commit 60649d443dc395243e74d2b3e05594ac0c43cfe3
> that introduces a null pointer dereference when the
> fdt_node_offset_by_compatible is called with "fdt"
> argument null.
>
> Reported-by: Julien Grall <jul...@xen.org>
> Fixes: 60649d443d ("arm/efi: Introduce xen,uefi-cfg-load DT property")
> Signed-off-by: Luca Fancellu <luca.fance...@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marq...@arm.com>
Cheers
Bertrand
> ---
> xen/arch/arm/efi/efi-boot.h | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/xen/arch/arm/efi/efi-boot.h b/xen/arch/arm/efi/efi-boot.h
> index a3e46453d4..e63dafac26 100644
> --- a/xen/arch/arm/efi/efi-boot.h
> +++ b/xen/arch/arm/efi/efi-boot.h
> @@ -593,7 +593,8 @@ static bool __init
> efi_arch_use_config_file(EFI_SYSTEM_TABLE *SystemTable)
> dtbfile.ptr = fdt;
> dtbfile.need_to_free = false; /* Config table memory can't be freed. */
>
> - if ( fdt_node_offset_by_compatible(fdt, 0, "multiboot,module") > 0 )
> + if ( fdt &&
> + (fdt_node_offset_by_compatible(fdt, 0, "multiboot,module") > 0) )
> {
> /* Locate chosen node */
> int node = fdt_subnode_offset(fdt, 0, "chosen");
> --
> 2.17.1
>
