mac80211: Check crypto_aead_encrypt for errors

crypto_aead_encrypt returns <0 on error, so if these calls are not checked,
execution may continue with failed encrypts.  It also seems that these two
crypto_aead_encrypt calls are the only instances in the codebase that are
not checked for errors.

Signed-off-by: Daniel Phan <daniel.phan36@gmail.com>
Link: https://lore.kernel.org/r/20210309204137.823268-1-daniel.phan36@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/aead_api.c

@@ -23,6 +23,7 @@ int aead_encrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad, size_t aad_len,
 	struct aead_request *aead_req;
 	int reqsize = sizeof(*aead_req) + crypto_aead_reqsize(tfm);
 	u8 *__aad;
+	int ret;
 
 	aead_req = kzalloc(reqsize + aad_len, GFP_ATOMIC);
 	if (!aead_req)
@@ -40,10 +41,10 @@ int aead_encrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad, size_t aad_len,
 	aead_request_set_crypt(aead_req, sg, sg, data_len, b_0);
 	aead_request_set_ad(aead_req, sg[0].length);
 
-	crypto_aead_encrypt(aead_req);
+	ret = crypto_aead_encrypt(aead_req);
 	kfree_sensitive(aead_req);
 
-	return 0;
+	return ret;
 }
 
 int aead_decrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad, size_t aad_len,

net/mac80211/aes_gmac.c

@@ -22,6 +22,7 @@ int ieee80211_aes_gmac(struct crypto_aead *tfm, const u8 *aad, u8 *nonce,
 	struct aead_request *aead_req;
 	int reqsize = sizeof(*aead_req) + crypto_aead_reqsize(tfm);
 	const __le16 *fc;
+	int ret;
 
 	if (data_len < GMAC_MIC_LEN)
 		return -EINVAL;
@@ -59,10 +60,10 @@ int ieee80211_aes_gmac(struct crypto_aead *tfm, const u8 *aad, u8 *nonce,
 	aead_request_set_crypt(aead_req, sg, sg, 0, iv);
 	aead_request_set_ad(aead_req, GMAC_AAD_LEN + data_len);
 
-	crypto_aead_encrypt(aead_req);
+	ret = crypto_aead_encrypt(aead_req);
 	kfree_sensitive(aead_req);
 
-	return 0;
+	return ret;
 }
 
 struct crypto_aead *ieee80211_aes_gmac_key_setup(const u8 key[],