crypto: api - Fix zeroing on free
Geert Uytterhoeven pointed out that we're not zeroing all the
memory when freeing a transform. This patch fixes it by calling
ksize to ensure that we zero everything in sight.
Reported-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/api.c b/crypto/api.c
index 9975a7b..efe77df 100644
--- a/crypto/api.c
+++ b/crypto/api.c
@@ -557,34 +557,34 @@
return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
-
+
/*
- * crypto_free_tfm - Free crypto transform
+ * crypto_destroy_tfm - Free crypto transform
+ * @mem: Start of tfm slab
* @tfm: Transform to free
*
- * crypto_free_tfm() frees up the transform and any associated resources,
+ * This function frees up the transform and any associated resources,
* then drops the refcount on the associated algorithm.
*/
-void crypto_free_tfm(struct crypto_tfm *tfm)
+void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm)
{
struct crypto_alg *alg;
int size;
- if (unlikely(!tfm))
+ if (unlikely(!mem))
return;
alg = tfm->__crt_alg;
- size = sizeof(*tfm) + alg->cra_ctxsize;
+ size = ksize(mem);
if (!tfm->exit && alg->cra_exit)
alg->cra_exit(tfm);
crypto_exit_ops(tfm);
crypto_mod_put(alg);
- memset(tfm, 0, size);
- kfree(tfm);
+ memset(mem, 0, size);
+ kfree(mem);
}
-
-EXPORT_SYMBOL_GPL(crypto_free_tfm);
+EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
int crypto_has_alg(const char *name, u32 type, u32 mask)
{
diff --git a/include/linux/crypto.h b/include/linux/crypto.h
index 3bacd71..1f2e902 100644
--- a/include/linux/crypto.h
+++ b/include/linux/crypto.h
@@ -552,7 +552,12 @@
const struct crypto_type *frontend,
u32 type, u32 mask);
struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask);
-void crypto_free_tfm(struct crypto_tfm *tfm);
+void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm);
+
+static inline void crypto_free_tfm(struct crypto_tfm *tfm)
+{
+ return crypto_destroy_tfm(tfm, tfm);
+}
int alg_test(const char *driver, const char *alg, u32 type, u32 mask);