(+ Stephen, Boris)
On Thu, 28 May 2020 at 01:26, Arvind Sankar <nivedita@xxxxxxxxxxxx> wrote:
>
> Commit
> 987053a30016 ("efi/x86: Move command-line initrd loading to efi_main")
> moved the command-line initrd loading into efi_main, with a check to
> ensure that it was attempted only if the EFI stub was booted via
> efi_pe_entry rather than the EFI handover entry.
>
> However, in the case where it was booted via handover entry, and thus an
> initrd may have already been loaded by the bootloader, it then wrote 0
> for the initrd address and size, removing any existing initrd.
>
> Fix this by checking if size is positive before setting the fields in
> the bootparams structure.
>
> Fixes: 987053a30016 ("efi/x86: Move command-line initrd loading to efi_main")
> Reported-by: Dan Williams <dan.j.williams@xxxxxxxxx>
> Tested-by: Dan Williams <dan.j.williams@xxxxxxxxx>
> Signed-off-by: Arvind Sankar <nivedita@xxxxxxxxxxxx>
Reviewed-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Apologies to all for the breakage, and for not catching this in review.
Ingo, Thomas, Boris: please apply this directly to efi/core asap.
Stephen: gives that this breaks the boot for a lot of people, you
might want to pull this into -next directly.
Thanks,
Ard.
> ---
> drivers/firmware/efi/libstub/x86-stub.c | 10 ++++++----
> 1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
> index 072b7cf40475..ceb8e16c8b75 100644
> --- a/drivers/firmware/efi/libstub/x86-stub.c
> +++ b/drivers/firmware/efi/libstub/x86-stub.c
> @@ -774,10 +774,12 @@ unsigned long efi_main(efi_handle_t handle,
> efi_err("Failed to load initrd!\n");
> goto fail;
> }
> - efi_set_u64_split(addr, &hdr->ramdisk_image,
> - &boot_params->ext_ramdisk_image);
> - efi_set_u64_split(size, &hdr->ramdisk_size,
> - &boot_params->ext_ramdisk_size);
> + if (size > 0) {
> + efi_set_u64_split(addr, &hdr->ramdisk_image,
> + &boot_params->ext_ramdisk_image);
> + efi_set_u64_split(size, &hdr->ramdisk_size,
> + &boot_params->ext_ramdisk_size);
> + }
> }
>
> /*
> --
> 2.26.2
>
