Re: [PATCH v7 04/17] luks2: Make sure all fields of output argument in luks2_parse_digest() are written to

[Patrick Steinhardt]

On Fri, Dec 04, 2020 at 10:43:33AM -0600, Glenn Washburn wrote:
> We should assume that the output argument "out" is uninitialized and could
> have random data. So, make sure to initialize the segments and keyslots bit
> fields because potentially not all bits of those fields are written to.
> Otherwise, the digest could say it belongs to keyslots and segments that it
> does not.
> 
> Signed-off-by: Glenn Washburn <development@efficientek.com>

Makes sense.

Signed-off-by: Patrick Steinhardt <ps@pks.im>

> ---
>  grub-core/disk/luks2.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/grub-core/disk/luks2.c b/grub-core/disk/luks2.c
> index bdb90e4b6..eadd529e9 100644
> --- a/grub-core/disk/luks2.c
> +++ b/grub-core/disk/luks2.c
> @@ -230,6 +230,7 @@ luks2_parse_digest (grub_luks2_digest_t *out, const 
> grub_json_t *digest)
>      return grub_error (GRUB_ERR_BAD_ARGUMENT,
>                      "Digest references no segments");
>  
> +  out->segments = 0;
>    for (i = 0; i < size; i++)
>      {
>        if (grub_json_getchild (&o, &segments, i) ||
> @@ -242,6 +243,7 @@ luks2_parse_digest (grub_luks2_digest_t *out, const 
> grub_json_t *digest)
>      return grub_error (GRUB_ERR_BAD_ARGUMENT,
>                      "Digest references no keyslots");
>  
> +  out->keyslots = 0;
>    for (i = 0; i < size; i++)
>      {
>        if (grub_json_getchild (&o, &keyslots, i) ||
> -- 
> 2.27.0
>

signature.asc
Description: PGP signature