Commit f93af41b authored by David Howells's avatar David Howells Committed by Jakub Kicinski
Browse files

rxrpc: Fix missing error checks for rxkad encryption/decryption failure 

Add error checking for failure of crypto_skcipher_en/decrypt() to various
rxkad function as the crypto functions can fail with ENOMEM at least.

Fixes: 17926a79 ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Closes: https://sashiko.dev/#/patchset/20260401105614.1696001-10-dhowells@redhat.com


Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260408121252.2249051-17-dhowells@redhat.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 2afd86cc

net/rxrpc/rxkad.c

+38 −19
Original line number Diff line number Diff line
@@ -197,6 +197,7 @@ static int rxkad_prime_packet_security(struct rxrpc_connection *conn, 
	struct rxrpc_crypt iv;

	__be32 *tmpbuf;

	size_t tmpsize = 4 * sizeof(__be32);

	int ret;



	_enter("");
@@ -225,13 +226,13 @@ static int rxkad_prime_packet_security(struct rxrpc_connection *conn, 
	skcipher_request_set_sync_tfm(req, ci);

	skcipher_request_set_callback(req, 0, NULL, NULL);

	skcipher_request_set_crypt(req, &sg, &sg, tmpsize, iv.x);

	crypto_skcipher_encrypt(req);

	ret = crypto_skcipher_encrypt(req);

	skcipher_request_free(req);



	memcpy(&conn->rxkad.csum_iv, tmpbuf + 2, sizeof(conn->rxkad.csum_iv));

	kfree(tmpbuf);

	_leave(" = 0");

	return 0;

	_leave(" = %d", ret);

	return ret;

}



/*
@@ -264,6 +265,7 @@ static int rxkad_secure_packet_auth(const struct rxrpc_call *call, 
	struct scatterlist sg;

	size_t pad;

	u16 check;

	int ret;



	_enter("");
@@ -286,11 +288,11 @@ static int rxkad_secure_packet_auth(const struct rxrpc_call *call, 
	skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);

	skcipher_request_set_callback(req, 0, NULL, NULL);

	skcipher_request_set_crypt(req, &sg, &sg, 8, iv.x);

	crypto_skcipher_encrypt(req);

	ret = crypto_skcipher_encrypt(req);

	skcipher_request_zero(req);



	_leave(" = 0");

	return 0;

	_leave(" = %d", ret);

	return ret;

}



/*
@@ -345,7 +347,7 @@ static int rxkad_secure_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb) 
	union {

		__be32 buf[2];

	} crypto __aligned(8);

	u32 x, y;

	u32 x, y = 0;

	int ret;



	_enter("{%d{%x}},{#%u},%u,",
@@ -376,8 +378,10 @@ static int rxkad_secure_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb) 
	skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);

	skcipher_request_set_callback(req, 0, NULL, NULL);

	skcipher_request_set_crypt(req, &sg, &sg, 8, iv.x);

	crypto_skcipher_encrypt(req);

	ret = crypto_skcipher_encrypt(req);

	skcipher_request_zero(req);

	if (ret < 0)

		goto out;



	y = ntohl(crypto.buf[1]);

	y = (y >> 16) & 0xffff;
@@ -413,6 +417,7 @@ static int rxkad_secure_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb) 
		memset(p + txb->pkt_len, 0, gap);

	}



out:

	skcipher_request_free(req);

	_leave(" = %d [set %x]", ret, y);

	return ret;
@@ -453,8 +458,10 @@ static int rxkad_verify_packet_1(struct rxrpc_call *call, struct sk_buff *skb, 
	skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);

	skcipher_request_set_callback(req, 0, NULL, NULL);

	skcipher_request_set_crypt(req, sg, sg, 8, iv.x);

	crypto_skcipher_decrypt(req);

	ret = crypto_skcipher_decrypt(req);

	skcipher_request_zero(req);

	if (ret < 0)

		return ret;



	/* Extract the decrypted packet length */

	if (skb_copy_bits(skb, sp->offset, &sechdr, sizeof(sechdr)) < 0)
@@ -531,10 +538,14 @@ static int rxkad_verify_packet_2(struct rxrpc_call *call, struct sk_buff *skb, 
	skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);

	skcipher_request_set_callback(req, 0, NULL, NULL);

	skcipher_request_set_crypt(req, sg, sg, sp->len, iv.x);

	crypto_skcipher_decrypt(req);

	ret = crypto_skcipher_decrypt(req);

	skcipher_request_zero(req);

	if (sg != _sg)

		kfree(sg);

	if (ret < 0) {

		WARN_ON_ONCE(ret != -ENOMEM);

		return ret;

	}



	/* Extract the decrypted packet length */

	if (skb_copy_bits(skb, sp->offset, &sechdr, sizeof(sechdr)) < 0)
@@ -602,8 +613,10 @@ static int rxkad_verify_packet(struct rxrpc_call *call, struct sk_buff *skb) 
	skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);

	skcipher_request_set_callback(req, 0, NULL, NULL);

	skcipher_request_set_crypt(req, &sg, &sg, 8, iv.x);

	crypto_skcipher_encrypt(req);

	ret = crypto_skcipher_encrypt(req);

	skcipher_request_zero(req);

	if (ret < 0)

		goto out;



	y = ntohl(crypto.buf[1]);

	cksum = (y >> 16) & 0xffff;
@@ -1077,21 +1090,23 @@ static int rxkad_decrypt_ticket(struct rxrpc_connection *conn, 
/*

 * decrypt the response packet

 */

static void rxkad_decrypt_response(struct rxrpc_connection *conn,

static int rxkad_decrypt_response(struct rxrpc_connection *conn,

				  struct rxkad_response *resp,

				  const struct rxrpc_crypt *session_key)

{

	struct skcipher_request *req = rxkad_ci_req;

	struct scatterlist sg[1];

	struct rxrpc_crypt iv;

	int ret;



	_enter(",,%08x%08x",

	       ntohl(session_key->n[0]), ntohl(session_key->n[1]));



	mutex_lock(&rxkad_ci_mutex);

	if (crypto_sync_skcipher_setkey(rxkad_ci, session_key->x,

					sizeof(*session_key)) < 0)

		BUG();

	ret = crypto_sync_skcipher_setkey(rxkad_ci, session_key->x,

					  sizeof(*session_key));

	if (ret < 0)

		goto unlock;



	memcpy(&iv, session_key, sizeof(iv));
@@ -1100,12 +1115,14 @@ static void rxkad_decrypt_response(struct rxrpc_connection *conn, 
	skcipher_request_set_sync_tfm(req, rxkad_ci);

	skcipher_request_set_callback(req, 0, NULL, NULL);

	skcipher_request_set_crypt(req, sg, sg, sizeof(resp->encrypted), iv.x);

	crypto_skcipher_decrypt(req);

	ret = crypto_skcipher_decrypt(req);

	skcipher_request_zero(req);



unlock:

	mutex_unlock(&rxkad_ci_mutex);



	_leave("");

	return ret;

}



/*
@@ -1198,7 +1215,9 @@ static int rxkad_verify_response(struct rxrpc_connection *conn, 


	/* use the session key from inside the ticket to decrypt the

	 * response */

	rxkad_decrypt_response(conn, response, &session_key);

	ret = rxkad_decrypt_response(conn, response, &session_key);

	if (ret < 0)

		goto temporary_error_free_ticket;



	if (ntohl(response->encrypted.epoch) != conn->proto.epoch ||

	    ntohl(response->encrypted.cid) != conn->proto.cid ||