Re: [PATCH][next] apparmor: Use struct_size() helper in kzalloc()

[John Johansen]

On 9/29/21 3:05 PM, Gustavo A. R. Silva wrote:
> Make use of the struct_size() helper instead of an open-coded version,
> in order to avoid any potential type mistakes or integer overflows that,
> in the worse scenario, could lead to heap overflows.
>> Link: https://github.com/KSPP/linux/issues/160
> Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>

nice

I will pull this into my tree
Acked-by: John Johansen <john.johansen@xxxxxxxxxxxxx>

> ---
>  security/apparmor/label.c  | 3 +--
>  security/apparmor/policy.c | 3 +--
>  2 files changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/security/apparmor/label.c b/security/apparmor/label.c
> index 6222fdfebe4e..0b0265da1926 100644
> --- a/security/apparmor/label.c
> +++ b/security/apparmor/label.c
> @@ -425,8 +425,7 @@ struct aa_label *aa_label_alloc(int size, struct aa_proxy *proxy, gfp_t gfp)
>  	AA_BUG(size < 1);
>  
>  	/*  + 1 for null terminator entry on vec */
> -	new = kzalloc(sizeof(*new) + sizeof(struct aa_profile *) * (size + 1),
> -			gfp);
> +	new = kzalloc(struct_size(new, vec, size + 1), gfp);
>  	AA_DEBUG("%s (%p)\n", __func__, new);
>  	if (!new)
>  		goto fail;
> diff --git a/security/apparmor/policy.c b/security/apparmor/policy.c
> index 17191a9eae41..5827dbdfbfca 100644
> --- a/security/apparmor/policy.c
> +++ b/security/apparmor/policy.c
> @@ -260,8 +260,7 @@ struct aa_profile *aa_alloc_profile(const char *hname, struct aa_proxy *proxy,
>  	struct aa_profile *profile;
>  
>  	/* freed by free_profile - usually through aa_put_profile */
> -	profile = kzalloc(sizeof(*profile) + sizeof(struct aa_profile *) * 2,
> -			  gfp);
> +	profile = kzalloc(struct_size(profile, label.vec, 2), gfp);
>  	if (!profile)
>  		return NULL;
>  
>