ksmbd: fix multi session connection failure

When RSS mode is enable, windows client do simultaneously send several
session requests to server. There is racy issue using
sess->ntlmssp.cryptkey on N connection : 1 session. So authetication
failed using wrong cryptkey on some session. This patch move cryptkey
to ksmbd_conn structure to use each cryptkey on connection.
Tested-by: Ziwei Xie <zw.xie@high-flyer.cn>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/ksmbd/auth.c

@@ -215,7 +215,7 @@ static int calc_ntlmv2_hash(struct ksmbd_session *sess, char *ntlmv2_hash,
  * Return:	0 on success, error number on error
  */
 int ksmbd_auth_ntlmv2(struct ksmbd_session *sess, struct ntlmv2_resp *ntlmv2,
-		      int blen, char *domain_name)
+		      int blen, char *domain_name, char *cryptkey)
 {
 	char ntlmv2_hash[CIFS_ENCPWD_SIZE];
 	char ntlmv2_rsp[CIFS_HMAC_MD5_HASH_SIZE];
@@ -256,7 +256,7 @@ int ksmbd_auth_ntlmv2(struct ksmbd_session *sess, struct ntlmv2_resp *ntlmv2,
 		goto out;
 	}
 
-	memcpy(construct, sess->ntlmssp.cryptkey, CIFS_CRYPTO_KEY_SIZE);
+	memcpy(construct, cryptkey, CIFS_CRYPTO_KEY_SIZE);
 	memcpy(construct + CIFS_CRYPTO_KEY_SIZE, &ntlmv2->blob_signature, blen);
 
 	rc = crypto_shash_update(CRYPTO_HMACMD5(ctx), construct, len);
@@ -295,7 +295,8 @@ int ksmbd_auth_ntlmv2(struct ksmbd_session *sess, struct ntlmv2_resp *ntlmv2,
  * Return:	0 on success, error number on error
  */
 int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob,
-				   int blob_len, struct ksmbd_session *sess)
+				   int blob_len, struct ksmbd_conn *conn,
+				   struct ksmbd_session *sess)
 {
 	char *domain_name;
 	unsigned int nt_off, dn_off;
@@ -324,7 +325,7 @@ int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob,
 
 	/* TODO : use domain name that imported from configuration file */
 	domain_name = smb_strndup_from_utf16((const char *)authblob + dn_off,
-					     dn_len, true, sess->conn->local_nls);
+					     dn_len, true, conn->local_nls);
 	if (IS_ERR(domain_name))
 		return PTR_ERR(domain_name);
 
@@ -333,7 +334,7 @@ int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob,
 		    domain_name);
 	ret = ksmbd_auth_ntlmv2(sess, (struct ntlmv2_resp *)((char *)authblob + nt_off),
 				nt_len - CIFS_ENCPWD_SIZE,
-				domain_name);
+				domain_name, conn->ntlmssp.cryptkey);
 	kfree(domain_name);
 	return ret;
 }
@@ -347,7 +348,7 @@ int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob,
  *
  */
 int ksmbd_decode_ntlmssp_neg_blob(struct negotiate_message *negblob,
-				  int blob_len, struct ksmbd_session *sess)
+				  int blob_len, struct ksmbd_conn *conn)
 {
 	if (blob_len < sizeof(struct negotiate_message)) {
 		ksmbd_debug(AUTH, "negotiate blob len %d too small\n",
@@ -361,7 +362,7 @@ int ksmbd_decode_ntlmssp_neg_blob(struct negotiate_message *negblob,
 		return -EINVAL;
 	}
 
-	sess->ntlmssp.client_flags = le32_to_cpu(negblob->NegotiateFlags);
+	conn->ntlmssp.client_flags = le32_to_cpu(negblob->NegotiateFlags);
 	return 0;
 }
 
@@ -375,14 +376,14 @@ int ksmbd_decode_ntlmssp_neg_blob(struct negotiate_message *negblob,
  */
 unsigned int
 ksmbd_build_ntlmssp_challenge_blob(struct challenge_message *chgblob,
-				   struct ksmbd_session *sess)
+				   struct ksmbd_conn *conn)
 {
 	struct target_info *tinfo;
 	wchar_t *name;
 	__u8 *target_name;
 	unsigned int flags, blob_off, blob_len, type, target_info_len = 0;
 	int len, uni_len, conv_len;
-	int cflags = sess->ntlmssp.client_flags;
+	int cflags = conn->ntlmssp.client_flags;
 
 	memcpy(chgblob->Signature, NTLMSSP_SIGNATURE, 8);
 	chgblob->MessageType = NtLmChallenge;
@@ -403,7 +404,7 @@ ksmbd_build_ntlmssp_challenge_blob(struct challenge_message *chgblob,
 	if (cflags & NTLMSSP_REQUEST_TARGET)
 		flags |= NTLMSSP_REQUEST_TARGET;
 
-	if (sess->conn->use_spnego &&
+	if (conn->use_spnego &&
 	    (cflags & NTLMSSP_NEGOTIATE_EXTENDED_SEC))
 		flags |= NTLMSSP_NEGOTIATE_EXTENDED_SEC;
 
@@ -414,7 +415,7 @@ ksmbd_build_ntlmssp_challenge_blob(struct challenge_message *chgblob,
 		return -ENOMEM;
 
 	conv_len = smb_strtoUTF16((__le16 *)name, ksmbd_netbios_name(), len,
-				  sess->conn->local_nls);
+				  conn->local_nls);
 	if (conv_len < 0 || conv_len > len) {
 		kfree(name);
 		return -EINVAL;
@@ -430,8 +431,8 @@ ksmbd_build_ntlmssp_challenge_blob(struct challenge_message *chgblob,
 	chgblob->TargetName.BufferOffset = cpu_to_le32(blob_off);
 
 	/* Initialize random conn challenge */
-	get_random_bytes(sess->ntlmssp.cryptkey, sizeof(__u64));
-	memcpy(chgblob->Challenge, sess->ntlmssp.cryptkey,
+	get_random_bytes(conn->ntlmssp.cryptkey, sizeof(__u64));
+	memcpy(chgblob->Challenge, conn->ntlmssp.cryptkey,
 	       CIFS_CRYPTO_KEY_SIZE);
 
 	/* Add Target Information to security buffer */

fs/ksmbd/auth.h

@@ -38,16 +38,16 @@ struct kvec;
 int ksmbd_crypt_message(struct ksmbd_conn *conn, struct kvec *iov,
 			unsigned int nvec, int enc);
 void ksmbd_copy_gss_neg_header(void *buf);
-int ksmbd_auth_ntlm(struct ksmbd_session *sess, char *pw_buf);
 int ksmbd_auth_ntlmv2(struct ksmbd_session *sess, struct ntlmv2_resp *ntlmv2,
-		      int blen, char *domain_name);
+		      int blen, char *domain_name, char *cryptkey);
 int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob,
-				   int blob_len, struct ksmbd_session *sess);
+				   int blob_len, struct ksmbd_conn *conn,
+				   struct ksmbd_session *sess);
 int ksmbd_decode_ntlmssp_neg_blob(struct negotiate_message *negblob,
-				  int blob_len, struct ksmbd_session *sess);
+				  int blob_len, struct ksmbd_conn *conn);
 unsigned int
 ksmbd_build_ntlmssp_challenge_blob(struct challenge_message *chgblob,
-				   struct ksmbd_session *sess);
+				   struct ksmbd_conn *conn);
 int ksmbd_krb5_authenticate(struct ksmbd_session *sess, char *in_blob,
 			    int in_len,	char *out_blob, int *out_len);
 int ksmbd_sign_smb2_pdu(struct ksmbd_conn *conn, char *key, struct kvec *iov,

fs/ksmbd/connection.h

@@ -72,12 +72,7 @@ struct ksmbd_conn {
 	int				connection_type;
 	struct ksmbd_stats		stats;
 	char				ClientGUID[SMB2_CLIENT_GUID_SIZE];
-	union {
-		/* pending trans request table */
-		struct trans_state	*recent_trans;
-		/* Used by ntlmssp */
-		char			*ntlmssp_cryptkey;
-	};
+	struct ntlmssp_auth		ntlmssp;
 
 	spinlock_t			llist_lock;
 	struct list_head		lock_list;

fs/ksmbd/mgmt/user_session.h

@@ -45,7 +45,6 @@ struct ksmbd_session {
 	int				state;
 	__u8				*Preauth_HashValue;
 
-	struct ntlmssp_auth		ntlmssp;
 	char				sess_key[CIFS_KEY_SIZE];
 
 	struct hlist_node		hlist;

fs/ksmbd/smb2pdu.c

@@ -1301,7 +1301,7 @@ static int ntlm_negotiate(struct ksmbd_work *work,
 	int sz, rc;
 
 	ksmbd_debug(SMB, "negotiate phase\n");
-	rc = ksmbd_decode_ntlmssp_neg_blob(negblob, negblob_len, work->sess);
+	rc = ksmbd_decode_ntlmssp_neg_blob(negblob, negblob_len, work->conn);
 	if (rc)
 		return rc;
 
@@ -1311,7 +1311,7 @@ static int ntlm_negotiate(struct ksmbd_work *work,
 	memset(chgblob, 0, sizeof(struct challenge_message));
 
 	if (!work->conn->use_spnego) {
-		sz = ksmbd_build_ntlmssp_challenge_blob(chgblob, work->sess);
+		sz = ksmbd_build_ntlmssp_challenge_blob(chgblob, work->conn);
 		if (sz < 0)
 			return -ENOMEM;
 
@@ -1327,7 +1327,7 @@ static int ntlm_negotiate(struct ksmbd_work *work,
 		return -ENOMEM;
 
 	chgblob = (struct challenge_message *)neg_blob;
-	sz = ksmbd_build_ntlmssp_challenge_blob(chgblob, work->sess);
+	sz = ksmbd_build_ntlmssp_challenge_blob(chgblob, work->conn);
 	if (sz < 0) {
 		rc = -ENOMEM;
 		goto out;
@@ -1470,7 +1470,7 @@ static int ntlm_authenticate(struct ksmbd_work *work)
 
 		authblob = user_authblob(conn, req);
 		sz = le16_to_cpu(req->SecurityBufferLength);
-		rc = ksmbd_decode_ntlmssp_auth_blob(authblob, sz, sess);
+		rc = ksmbd_decode_ntlmssp_auth_blob(authblob, sz, conn, sess);
 		if (rc) {
 			set_user_flag(sess->user, KSMBD_USER_FLAG_BAD_PASSWORD);
 			ksmbd_debug(SMB, "authentication failed\n");