Re: [bug] crypto/vmx/p8_ghash memory corruption in 4.8-rc7

From: Jan Stancek
Date: Wed Sep 28 2016 - 04:59:59 EST


> Jan,
>
> Can you check if the problem occurs with this patch?

No issues in over-night test with this patch.

> --- a/drivers/crypto/vmx/vmx.c
> +++ b/drivers/crypto/vmx/vmx.c
> @@ -28,6 +28,8 @@
> #include <asm/cputable.h>
> #include <crypto/internal/hash.h>
>
> +int p8_ghash_fallback_descsize(void);
> +
> extern struct shash_alg p8_ghash_alg;
> extern struct crypto_alg p8_aes_alg;
> extern struct crypto_alg p8_aes_cbc_alg;
> @@ -45,6 +47,7 @@ int __init p8_init(void)
> {
> int ret = 0;
> struct crypto_alg **alg_it;
> + int ghash_descsize;
>
> for (alg_it = algs; *alg_it; alg_it++) {
> ret = crypto_register_alg(*alg_it);
> @@ -59,6 +62,12 @@ int __init p8_init(void)
> if (ret)
> return ret;
>
> + ghash_descsize = p8_ghash_fallback_descsize();
> + if (ghash_descsize < 0) {
> + printk(KERN_ERR "Cannot get descsize for p8_ghash fallback\n");
> + return ghash_descsize;
> + }
> + p8_ghash_alg.descsize += ghash_descsize;
> ret = crypto_register_shash(&p8_ghash_alg);
> if (ret) {
> for (alg_it = algs; *alg_it; alg_it++)

I'd suggest to move this inside vmx/ghash.c to a new function, so all p8_ghash
related code is at single place. Then p8_init() would just call the new
function:
- ret = crypto_register_shash(&p8_ghash_alg);
+ ret = register_p8_ghash();

Regards,
Jan