[PATCH] efi_loader: Fix potential deref-after-null

[Heinrich Schuchardt]

On 2/2/25 18:59, Maks Mishin wrote:
> After having been compared to a NULL value at efi_disk.c:426,
> pointer 'part_info' is dereferenced at efi_disk.c:534.
> 
> Signed-off-by: Maks Mishin <maks.mishinFZ at gmail.com>
> ---
>   lib/efi_loader/efi_disk.c | 16 +++++++++-------
>   1 file changed, 9 insertions(+), 7 deletions(-)
> 
> diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
> index 1f3de0a233..83e8eb6fe4 100644
> --- a/lib/efi_loader/efi_disk.c
> +++ b/lib/efi_loader/efi_disk.c
> @@ -531,13 +531,15 @@ static efi_status_t efi_disk_add_dev(
>   
>   	/* Store first EFI system partition */
>   	if (part && efi_system_partition.uclass_id == UCLASS_INVALID) {
> -		if (part_info->bootable & PART_EFI_SYSTEM_PARTITION) {
> -			efi_system_partition.uclass_id = desc->uclass_id;
> -			efi_system_partition.devnum = desc->devnum;
> -			efi_system_partition.part = part;
> -			EFI_PRINT("EFI system partition: %s %x:%x\n",
> -				  blk_get_uclass_name(desc->uclass_id),
> -				  desc->devnum, part);
> +		if (part_info) {
> +			if (part_info->bootable & PART_EFI_SYSTEM_PARTITION) {

Hello Maks,

Thank you for spotting this and providing a patch.

U-Boot has scripts/get_maintainer.pl to find whom patches should be 
addressed to.

We could use a single if statement with &&. But that is just a matter of 
taste.

Reviewed-by: Heinrich Schuchardt <xypron.glpk at gmx.de>

> +				efi_system_partition.uclass_id = desc->uclass_id;
> +				efi_system_partition.devnum = desc->devnum;
> +				efi_system_partition.part = part;
> +				EFI_PRINT("EFI system partition: %s %x:%x\n",
> +					blk_get_uclass_name(desc->uclass_id),
> +					desc->devnum, part);
> +			}
>   		}
>   	}
>   	return EFI_SUCCESS;