Re: [PATCH V2] net/nfc/nci: fix infoleak in struct nci_set_config_param

From: Krzysztof Kozlowski
Date: Wed Mar 02 2022 - 04:02:25 EST


On 02/03/2022 04:33, cgel.zte@xxxxxxxxx wrote:
> From: "Minghao Chi (CGEL ZTE)" <chi.minghao@xxxxxxxxxx>
>
> On 64-bit systems, struct nci_set_config_param has
> an added padding of 7 bytes between struct members
> id and len. Even though all struct members are initialized,
> the 7-byte hole will contain data from the kernel stack.
> This patch zeroes out struct nci_set_config_param before
> usage, preventing infoleaks to userspace.
>
> v1->v2:
> -Modify the title.
> -Add explanatory information.

Changelog goes below ---.

> Reported-by: Zeal Robot <zealci@xxxxxxxxxx>

Why do you ignore the comment about missing report?

> Signed-off-by: Minghao Chi (CGEL ZTE) <chi.minghao@xxxxxxxxxx>
> ---
> net/nfc/nci/core.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/net/nfc/nci/core.c b/net/nfc/nci/core.c
> index d2537383a3e8..32be42be1152 100644
> --- a/net/nfc/nci/core.c
> +++ b/net/nfc/nci/core.c
> @@ -641,6 +641,7 @@ int nci_set_config(struct nci_dev *ndev, __u8 id, size_t len, const __u8 *val)
> if (!val || !len)
> return 0;
>
> + memset(&param, 0x0, sizeof(param));

You ignored the comment here as well. That's not how a v2 should be
sent... if you don't agree with comments, we need to keep discussing.

> param.id = id;
> param.len = len;
> param.val = val;


Best regards,
Krzysztof