Re: [PATCH v2] efi: fix panic in kdump kernel

[Ard Biesheuvel]

On Sat, 23 Mar 2024 at 08:33, Oleksandr Tymoshenko <ovt@xxxxxxxxxx> wrote:
>
> Check if get_next_variable() is actually valid pointer before
> calling it. In kdump kernel this method is set to NULL that causes
> panic during the kexec-ed kernel boot.
>
> Tested with QEMU and OVMF firmware.
>
> Fixes: bad267f9e18f ("efi: verify that variable services are supported")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Oleksandr Tymoshenko <ovt@xxxxxxxxxx>

Thanks. Queued as a fix.

> ---
> Changes in v2:
>   - Style fix
>   - Added Cc: stable
>   - Added Fixes: trailer
> ---
>  drivers/firmware/efi/efi.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
> index 8859fb0b006d..fdf07dd6f459 100644
> --- a/drivers/firmware/efi/efi.c
> +++ b/drivers/firmware/efi/efi.c
> @@ -203,6 +203,8 @@ static bool generic_ops_supported(void)
>
>         name_size = sizeof(name);
>
> +       if (!efi.get_next_variable)
> +               return false;
>         status = efi.get_next_variable(&name_size, &name, &guid);
>         if (status == EFI_UNSUPPORTED)
>                 return false;
> --
> 2.44.0.396.g6e790dbe36-goog
>