crypto: drbg - use kmalloc instead of kzalloc for V and C

When allocating V, C, the zeroization is only needed when
allocating a new instance of the DRBG, i.e. when performing an
initial seeding. For all other allocations, the memcpy implemented in
drbg_copy_drbg ensures that the memory is filled with the correct
information.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 8 insertions, 3 deletions

diff --git a/crypto/drbg.c b/crypto/drbg.c
index 86cffc600acd..ebe0afc4e94b 100644
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -1142,6 +1142,11 @@ static int drbg_seed(struct drbg_state *drbg, struct drbg_string *pers,
                 pr_devel("DRBG: using personalization string\n");
         }
 
+        if (!reseed) {
+                memset(drbg->V, 0, drbg_statelen(drbg));
+                memset(drbg->C, 0, drbg_statelen(drbg));
+        }
+
         ret = drbg->d_ops->update(drbg, &seedlist, reseed);
         if (ret)
                 goto out;
@@ -1186,14 +1191,14 @@ static inline int drbg_alloc_state(struct drbg_state *drbg)
         if (!drbg)
                 return -EINVAL;
 
-        drbg->V = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
+        drbg->V = kmalloc(drbg_statelen(drbg), GFP_KERNEL);
         if (!drbg->V)
                 goto err;
-        drbg->C = kzalloc(drbg_statelen(drbg), GFP_KERNEL);
+        drbg->C = kmalloc(drbg_statelen(drbg), GFP_KERNEL);
         if (!drbg->C)
                 goto err;
 #ifdef CONFIG_CRYPTO_FIPS
-        drbg->prev = kzalloc(drbg_blocklen(drbg), GFP_KERNEL);
+        drbg->prev = kmalloc(drbg_blocklen(drbg), GFP_KERNEL);
         if (!drbg->prev)
                 goto err;
         drbg->fips_primed = false;