From ab172f4f42626549b02bada05f09e3f2b0cc26ec Mon Sep 17 00:00:00 2001
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Thu, 2 Oct 2025 17:45:39 +0800
Subject: [PATCH] crypto: rng - Ensure set_ent is always present

commit c0d36727bf39bb16ef0a67ed608e279535ebf0da upstream.

Ensure that set_ent is always set since only drbg provides it.

Fixes: 77ebdabe8de7 ("crypto: af_alg - add extra parameters for DRBG interface")
Reported-by: Yiqi Sun <sunyiqixm@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 crypto/rng.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/crypto/rng.c b/crypto/rng.c
index 279dffdebf59..e462031fef68 100644
--- a/crypto/rng.c
+++ b/crypto/rng.c
@@ -197,6 +197,11 @@ out:
 EXPORT_SYMBOL_GPL(crypto_del_default_rng);
 #endif
 
+static void rng_default_set_ent(struct crypto_rng *tfm, const u8 *data,
+				unsigned int len)
+{
+}
+
 int crypto_register_rng(struct rng_alg *alg)
 {
 	struct crypto_istat_rng *istat = rng_get_stat(alg);
@@ -212,6 +217,9 @@ int crypto_register_rng(struct rng_alg *alg)
 	if (IS_ENABLED(CONFIG_CRYPTO_STATS))
 		memset(istat, 0, sizeof(*istat));
 
+	if (!alg->set_ent)
+		alg->set_ent = rng_default_set_ent;
+
 	return crypto_register_alg(base);
 }
 EXPORT_SYMBOL_GPL(crypto_register_rng);