Hi Nicola,
> On 24 Jun 2025, at 02:20, victorm.l...@amd.com wrote:
>
> From: Nicola Vetrini <nicola.vetr...@bugseng.com>
>
> Use {get,put}_unaligned_t to ensure that reads and writes are
> safe to perform even on potentially misaligned pointers.
>
Make sense as we convert a void* to uint32_t * so might be misaligned.
> Signed-off-by: Nicola Vetrini <nicola.vetr...@bugseng.com>
> Signed-off-by: Victor Lira <victorm.l...@amd.com>
Acked-by: Bertrand Marquis <bertrand.marq...@arm.com>
Cheers
Bertrand
> ---
> Cc: Andrew Cooper <andrew.coop...@citrix.com>
> Cc: Anthony PERARD <anthony.per...@vates.tech>
> Cc: Michal Orzel <michal.or...@amd.com>
> Cc: Jan Beulich <jbeul...@suse.com>
> Cc: Julien Grall <jul...@xen.org>
> Cc: Roger Pau Monné <roger....@citrix.com>
> Cc: Stefano Stabellini <sstabell...@kernel.org>
> Cc: Nicola Vetrini <nicola.vetr...@bugseng.com>
> Cc: Federico Serafini <federico.seraf...@bugseng.com>
> Cc: Bertrand Marquis <bertrand.marq...@arm.com>
> ---
> xen/arch/arm/efi/efi-boot.h | 9 +++++----
> xen/common/device-tree/bootfdt.c | 3 ++-
> 2 files changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/xen/arch/arm/efi/efi-boot.h b/xen/arch/arm/efi/efi-boot.h
> index ee80560e13..12dbb6961f 100644
> --- a/xen/arch/arm/efi/efi-boot.h
> +++ b/xen/arch/arm/efi/efi-boot.h
> @@ -9,6 +9,7 @@
>
> #include <xen/device_tree.h>
> #include <xen/libfdt/libfdt.h>
> +#include <xen/unaligned.h>
> #include <asm/setup.h>
> #include <asm/smp.h>
>
> @@ -85,7 +86,7 @@ static int __init setup_chosen_node(void *fdt, int
> *addr_cells, int *size_cells)
> *addr_cells = 2;
> }
> else
> - *addr_cells = fdt32_to_cpu(*((uint32_t *)prop->data));
> + *addr_cells = fdt32_to_cpu(get_unaligned_t(uint32_t, prop->data));
>
> prop = fdt_get_property(fdt, node, "#size-cells", &len);
> if ( !prop )
> @@ -96,7 +97,7 @@ static int __init setup_chosen_node(void *fdt, int
> *addr_cells, int *size_cells)
> *size_cells = 2;
> }
> else
> - *size_cells = fdt32_to_cpu(*((uint32_t *)prop->data));
> + *size_cells = fdt32_to_cpu(get_unaligned_t(uint32_t, prop->data));
>
> /*
> * Make sure ranges is empty if it exists, otherwise create empty ranges
> @@ -824,7 +825,7 @@ static int __init handle_dom0less_domain_node(const
> EFI_LOADED_IMAGE *loaded_ima
> return ERROR_MISSING_DT_PROPERTY;
> }
>
> - addr_cells = fdt32_to_cpu(*((uint32_t *)prop->data));
> + addr_cells = fdt32_to_cpu(get_unaligned_t(uint32_t, prop->data));
>
> prop = fdt_get_property(fdt_efi, domain_node, "#size-cells", &len);
> if ( !prop )
> @@ -833,7 +834,7 @@ static int __init handle_dom0less_domain_node(const
> EFI_LOADED_IMAGE *loaded_ima
> return ERROR_MISSING_DT_PROPERTY;
> }
>
> - size_cells = fdt32_to_cpu(*((uint32_t *)prop->data));
> + size_cells = fdt32_to_cpu(get_unaligned_t(uint32_t, prop->data));
>
> /* Check for nodes compatible with multiboot,module inside this node */
> for ( module_node = fdt_first_subnode(fdt_efi, domain_node);
> diff --git a/xen/common/device-tree/bootfdt.c
> b/xen/common/device-tree/bootfdt.c
> index 529c91e603..9f255027ea 100644
> --- a/xen/common/device-tree/bootfdt.c
> +++ b/xen/common/device-tree/bootfdt.c
> @@ -13,6 +13,7 @@
> #include <xen/lib.h>
> #include <xen/libfdt/libfdt-xen.h>
> #include <xen/sort.h>
> +#include <xen/unaligned.h>
> #include <xsm/xsm.h>
> #include <asm/setup.h>
> #ifdef CONFIG_STATIC_SHM
> @@ -213,7 +214,7 @@ u32 __init device_tree_get_u32(const void *fdt, int node,
> if ( !prop || prop->len < sizeof(u32) )
> return dflt;
>
> - return fdt32_to_cpu(*(uint32_t*)prop->data);
> + return fdt32_to_cpu(get_unaligned_t(uint32_t, prop->data));
> }
>
> /**
> --
> 2.25.1
