crypto: algapi - make unregistration functions return void

Some of the algorithm unregistration functions return -ENOENT when asked
to unregister a non-registered algorithm, while others always return 0
or always return void.  But no users check the return value, except for
two of the bulk unregistration functions which print a message on error
but still always return 0 to their caller, and crypto_del_alg() which
calls crypto_unregister_instance() which always returns 0.

Since unregistering a non-registered algorithm is always a kernel bug
but there isn't anything callers should do to handle this situation at
runtime, let's simplify things by making all the unregistration
functions return void, and moving the error message into
crypto_unregister_alg() and upgrading it to a WARN().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

6 files changed, 22 insertions, 37 deletions

diff --git a/crypto/acompress.c b/crypto/acompress.c
index abadcb03..84a76723 100644
--- a/crypto/acompress.c
+++ b/crypto/acompress.c
@@ -151,9 +151,9 @@ int crypto_register_acomp(struct acomp_alg *alg)
 }
 EXPORT_SYMBOL_GPL(crypto_register_acomp);
 
-int crypto_unregister_acomp(struct acomp_alg *alg)
+void crypto_unregister_acomp(struct acomp_alg *alg)
 {
-	return crypto_unregister_alg(&alg->base);
+	crypto_unregister_alg(&alg->base);
 }
 EXPORT_SYMBOL_GPL(crypto_unregister_acomp);
 
diff --git a/crypto/ahash.c b/crypto/ahash.c
index 3815b363..181bd851 100644
--- a/crypto/ahash.c
+++ b/crypto/ahash.c
@@ -598,9 +598,9 @@ int crypto_register_ahash(struct ahash_alg *alg)
 }
 EXPORT_SYMBOL_GPL(crypto_register_ahash);
 
-int crypto_unregister_ahash(struct ahash_alg *alg)
+void crypto_unregister_ahash(struct ahash_alg *alg)
 {
-	return crypto_unregister_alg(&alg->halg.base);
+	crypto_unregister_alg(&alg->halg.base);
 }
 EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
 
diff --git a/crypto/algapi.c b/crypto/algapi.c
index 9589b3f0..fe57b4f6 100644
--- a/crypto/algapi.c
+++ b/crypto/algapi.c
@@ -442,7 +442,7 @@ static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
 	return 0;
 }
 
-int crypto_unregister_alg(struct crypto_alg *alg)
+void crypto_unregister_alg(struct crypto_alg *alg)
 {
 	int ret;
 	LIST_HEAD(list);
@@ -451,15 +451,14 @@ int crypto_unregister_alg(struct crypto_alg *alg)
 	ret = crypto_remove_alg(alg, &list);
 	up_write(&crypto_alg_sem);
 
-	if (ret)
-		return ret;
+	if (WARN(ret, "Algorithm %s is not registered", alg->cra_driver_name))
+		return;
 
 	BUG_ON(refcount_read(&alg->cra_refcnt) != 1);
 	if (alg->cra_destroy)
 		alg->cra_destroy(alg);
 
 	crypto_remove_final(&list);
-	return 0;
 }
 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
 
@@ -483,18 +482,12 @@ err:
 }
 EXPORT_SYMBOL_GPL(crypto_register_algs);
 
-int crypto_unregister_algs(struct crypto_alg *algs, int count)
+void crypto_unregister_algs(struct crypto_alg *algs, int count)
 {
-	int i, ret;
-
-	for (i = 0; i < count; i++) {
-		ret = crypto_unregister_alg(&algs[i]);
-		if (ret)
-			pr_err("Failed to unregister %s %s: %d\n",
-			       algs[i].cra_driver_name, algs[i].cra_name, ret);
-	}
+	int i;
 
-	return 0;
+	for (i = 0; i < count; i++)
+		crypto_unregister_alg(&algs[i]);
 }
 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
 
@@ -639,7 +632,7 @@ err:
 }
 EXPORT_SYMBOL_GPL(crypto_register_instance);
 
-int crypto_unregister_instance(struct crypto_instance *inst)
+void crypto_unregister_instance(struct crypto_instance *inst)
 {
 	LIST_HEAD(list);
 
@@ -651,8 +644,6 @@ int crypto_unregister_instance(struct crypto_instance *inst)
 	up_write(&crypto_alg_sem);
 
 	crypto_remove_final(&list);
-
-	return 0;
 }
 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
 
diff --git a/crypto/crypto_user_base.c b/crypto/crypto_user_base.c
index b785c476..3fa20f12 100644
--- a/crypto/crypto_user_base.c
+++ b/crypto/crypto_user_base.c
@@ -323,7 +323,8 @@ static int crypto_del_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
 	if (refcount_read(&alg->cra_refcnt) > 2)
 		goto drop_alg;
 
-	err = crypto_unregister_instance((struct crypto_instance *)alg);
+	crypto_unregister_instance((struct crypto_instance *)alg);
+	err = 0;
 
 drop_alg:
 	crypto_mod_put(alg);
diff --git a/crypto/scompress.c b/crypto/scompress.c
index 4d50750d..738f4f8f 100644
--- a/crypto/scompress.c
+++ b/crypto/scompress.c
@@ -266,9 +266,9 @@ int crypto_register_scomp(struct scomp_alg *alg)
 }
 EXPORT_SYMBOL_GPL(crypto_register_scomp);
 
-int crypto_unregister_scomp(struct scomp_alg *alg)
+void crypto_unregister_scomp(struct scomp_alg *alg)
 {
-	return crypto_unregister_alg(&alg->base);
+	crypto_unregister_alg(&alg->base);
 }
 EXPORT_SYMBOL_GPL(crypto_unregister_scomp);
 
diff --git a/crypto/shash.c b/crypto/shash.c
index 8042bb0d..7243f60d 100644
--- a/crypto/shash.c
+++ b/crypto/shash.c
@@ -520,9 +520,9 @@ int crypto_register_shash(struct shash_alg *alg)
 }
 EXPORT_SYMBOL_GPL(crypto_register_shash);
 
-int crypto_unregister_shash(struct shash_alg *alg)
+void crypto_unregister_shash(struct shash_alg *alg)
 {
-	return crypto_unregister_alg(&alg->base);
+	crypto_unregister_alg(&alg->base);
 }
 EXPORT_SYMBOL_GPL(crypto_unregister_shash);
 
@@ -546,19 +546,12 @@ err:
 }
 EXPORT_SYMBOL_GPL(crypto_register_shashes);
 
-int crypto_unregister_shashes(struct shash_alg *algs, int count)
+void crypto_unregister_shashes(struct shash_alg *algs, int count)
 {
-	int i, ret;
-
-	for (i = count - 1; i >= 0; --i) {
-		ret = crypto_unregister_shash(&algs[i]);
-		if (ret)
-			pr_err("Failed to unregister %s %s: %d\n",
-			       algs[i].base.cra_driver_name,
-			       algs[i].base.cra_name, ret);
-	}
+	int i;
 
-	return 0;
+	for (i = count - 1; i >= 0; --i)
+		crypto_unregister_shash(&algs[i]);
 }
 EXPORT_SYMBOL_GPL(crypto_unregister_shashes);