Re: [PATCH] x86/sev: Use kfree_sensitive() when freeing a SNP message descriptor

[Tom Lendacky]

On 1/12/26 05:41, Borislav Petkov wrote:
> On Sat, Dec 20, 2025 at 03:25:46PM +0100, Julia Lawall wrote:
>> cocci warnings: (new ones prefixed by >>)
>>>> arch/x86/coco/sev/core.c:2838:12-13: WARNING opportunity for kfree_sensitive/kvfree_sensitive (memset at line 2837)
> 
> From: "Borislav Petkov (AMD)" <bp@xxxxxxxxx>
> Date: Mon, 12 Jan 2026 12:37:49 +0100
> 
> Use the proper helper instead of an open-coded variant.
> 
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Reported-by: Julia Lawall <julia.lawall@xxxxxxxx>
> Closes: https://lore.kernel.org/r/202512202235.WHPQkLZu-lkp@xxxxxxxxx
> Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>

Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
> ---
>  arch/x86/coco/sev/core.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/arch/x86/coco/sev/core.c b/arch/x86/coco/sev/core.c
> index 379e0c09c7f3..38dad3f5f491 100644
> --- a/arch/x86/coco/sev/core.c
> +++ b/arch/x86/coco/sev/core.c
> @@ -1632,8 +1632,7 @@ void snp_msg_free(struct snp_msg_desc *mdesc)
>  	free_shared_pages(mdesc->request, sizeof(struct snp_guest_msg));
>  	iounmap((__force void __iomem *)mdesc->secrets);
>  
> -	memset(mdesc, 0, sizeof(*mdesc));
> -	kfree(mdesc);
> +	kfree_sensitive(mdesc);
>  }
>  EXPORT_SYMBOL_GPL(snp_msg_free);
>