commit d4fdc2dfaa755e0bf22de6a2774cac2e5ae45cf4
author Eric Biggers <ebiggers@google.com> Thu Jan 02 20:04:40 2020 -0800
committer Herbert Xu <herbert@gondor.apana.org.au> Thu Jan 09 11:30:58 2020 +0800
tree 18c2e44d234eaff00fbb2b9ae243d4ea69619651
parent a24a1fd731274ebbca873000e2c7fbe8224ae4c8

crypto: algapi - enforce that all instances have a ->free() method

All instances need to have a ->free() method, but people could forget to
set it and then not notice if the instance is never unregistered.  To
help detect this bug earlier, don't allow an instance without a ->free()
method to be registered, and complain loudly if someone tries to do it.

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

crypto/aead.c

diff --git a/crypto/aead.c b/crypto/aead.c
index 7707d32..1699109 100644
--- a/crypto/aead.c
+++ b/crypto/aead.c
@@ -288,6 +288,9 @@ int aead_register_instance(struct crypto_template *tmpl,
 {
 	int err;
 
+	if (WARN_ON(!inst->free))
+		return -EINVAL;
+
 	err = aead_prepare_alg(&inst->alg);
 	if (err)
 		return err;

crypto/ahash.c

diff --git a/crypto/ahash.c b/crypto/ahash.c
index cd5d984..68a0f0c 100644
--- a/crypto/ahash.c
+++ b/crypto/ahash.c
@@ -656,6 +656,9 @@ int ahash_register_instance(struct crypto_template *tmpl,
 {
 	int err;
 
+	if (WARN_ON(!inst->free))
+		return -EINVAL;
+
 	err = ahash_prepare_alg(&inst->alg);
 	if (err)
 		return err;

crypto/akcipher.c

diff --git a/crypto/akcipher.c b/crypto/akcipher.c
index eeed6c1..f866085 100644
--- a/crypto/akcipher.c
+++ b/crypto/akcipher.c
@@ -147,6 +147,8 @@ EXPORT_SYMBOL_GPL(crypto_unregister_akcipher);
 int akcipher_register_instance(struct crypto_template *tmpl,
 			       struct akcipher_instance *inst)
 {
+	if (WARN_ON(!inst->free))
+		return -EINVAL;
 	akcipher_prepare_alg(&inst->alg);
 	return crypto_register_instance(tmpl, akcipher_crypto_instance(inst));
 }

crypto/shash.c

diff --git a/crypto/shash.c b/crypto/shash.c
index 70faf28..c075b26 100644
--- a/crypto/shash.c
+++ b/crypto/shash.c
@@ -577,6 +577,9 @@ int shash_register_instance(struct crypto_template *tmpl,
 {
 	int err;
 
+	if (WARN_ON(!inst->free))
+		return -EINVAL;
+
 	err = shash_prepare_alg(&inst->alg);
 	if (err)
 		return err;

crypto/skcipher.c

diff --git a/crypto/skcipher.c b/crypto/skcipher.c
index 42add1e..7221def 100644
--- a/crypto/skcipher.c
+++ b/crypto/skcipher.c
@@ -865,6 +865,9 @@ int skcipher_register_instance(struct crypto_template *tmpl,
 {
 	int err;
 
+	if (WARN_ON(!inst->free))
+		return -EINVAL;
+
 	err = skcipher_prepare_alg(&inst->alg);
 	if (err)
 		return err;