Code:  static unsigned int seedsize(struct crypto_alg *alg)
 {
 	struct rng_alg *ralg = container_of(alg, struct rng_alg, base);
 
	return alg->cra_rng.rng_make_random ?
	       alg->cra_rng.seedsize : ralg->seedsize;
 }

Vulnerability Type: DoS 
CWE ID: CWE-476
Summary: The rngapi_reset function in crypto/rng.c in the Linux kernel before 4.2 allows attackers to cause a denial of service (NULL pointer dereference).
Commit Message: crypto: rng - Remove old low-level rng interface

Now that all rng implementations have switched over to the new
interface, we can remove the old low-level interface.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>