Re: [PATCH 1/1] efi/libstub: setup_graphics() do not return random data

From: Ard Biesheuvel
Date: Mon Apr 27 2020 - 02:52:43 EST


On Sun, 26 Apr 2020 at 21:49, Heinrich Schuchardt <xypron.glpk@xxxxxx> wrote:
>
> Currently setup_graphics() ignores the return value of efi_setup_gop(). As
> AllocatePool() does not zero out memory the screen information table will
> contain random data in this case.
>
> We should free the screen information table if efi_setup_gop() returns an
> error code.
>
> Signed-off-by: Heinrich Schuchardt <xypron.glpk@xxxxxx>

Thanks Heinrich

I will take this as a fix


> ---
> drivers/firmware/efi/libstub/efi-stub.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c
> index ee225b323687..60377e5ceab3 100644
> --- a/drivers/firmware/efi/libstub/efi-stub.c
> +++ b/drivers/firmware/efi/libstub/efi-stub.c
> @@ -55,7 +55,11 @@ static struct screen_info *setup_graphics(void)
> si = alloc_screen_info();
> if (!si)
> return NULL;
> - efi_setup_gop(si, &gop_proto, size);
> + status = efi_setup_gop(si, &gop_proto, size);
> + if (status != EFI_SUCCESS) {
> + free_screen_info(si);
> + return NULL;
> + }
> }
> return si;
> }
> --
> 2.26.2
>