Re: [PATCH] crypto: cavium - prevent integer overflow loading firmware

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, Sep 01, 2022 at 06:32:53PM +0300, Dan Carpenter wrote:
>
> @@ -263,7 +264,13 @@ static int cpt_ucode_load_fw(struct cpt_device *cpt, const u8 *fw, bool is_ae)
>  	ucode = (struct ucode_header *)fw_entry->data;
>  	mcode = &cpt->mcode[cpt->next_mc_idx];
>  	memcpy(mcode->version, (u8 *)fw_entry->data, CPT_UCODE_VERSION_SZ);
> -	mcode->code_size = ntohl(ucode->code_length) * 2;
> +
> +	code_length = ntohl(ucode->code_length);
> +	if (code_length >= INT_MAX / 2) {
> +		ret = -EINVAL;
> +		goto fw_release;
> +	}
> +	mcode->code_size = code_length;

Where did the "* 2" go?

BTW, what is the threat model here? If the firmware metadata can't
be trusted, shouldn't we be capping the firmware size at a level
a lot lower than INT_MAX?

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt



[Index of Archives]     [Kernel]     [Gnu Classpath]     [Gnu Crypto]     [DM Crypt]     [Netfilter]     [Bugtraq]
  Powered by Linux