Merge tag '5.20-rc-ksmbd-server-fixes' of git://git.samba.org/ksmbd

Pull ksmbd updates from Steve French:

 - fixes for memory access bugs (out of bounds access, oops, leak)

 - multichannel fixes

 - session disconnect performance improvement, and session register
   improvement

 - cleanup

* tag '5.20-rc-ksmbd-server-fixes' of git://git.samba.org/ksmbd:
  ksmbd: fix heap-based overflow in set_ntacl_dacl()
  ksmbd: prevent out of bound read for SMB2_TREE_CONNNECT
  ksmbd: prevent out of bound read for SMB2_WRITE
  ksmbd: fix use-after-free bug in smb2_tree_disconect
  ksmbd: fix memory leak in smb2_handle_negotiate
  ksmbd: fix racy issue while destroying session on multichannel
  ksmbd: use wait_event instead of schedule_timeout()
  ksmbd: fix kernel oops from idr_remove()
  ksmbd: add channel rwlock
  ksmbd: replace sessions list in connection with xarray
  MAINTAINERS: ksmbd: add entry for documentation
  ksmbd: remove unused ksmbd_share_configs_cleanup function

20 files changed, 322 insertions, 220 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 56ca13d5155e..b7221f4143cb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11063,6 +11063,7 @@ R:	Sergey Senozhatsky <senozhatsky@chromium.org>
 L:	linux-cifs@vger.kernel.org
 S:	Maintained
 T:	git git://git.samba.org/ksmbd.git
+F:	Documentation/filesystems/cifs/ksmbd.rst
 F:	fs/ksmbd/
 F:	fs/smbfs_common/
 
diff --git a/fs/ksmbd/auth.c b/fs/ksmbd/auth.c
index 911444d21267..c5a5c7b90d72 100644
--- a/fs/ksmbd/auth.c
+++ b/fs/ksmbd/auth.c
@@ -121,8 +121,8 @@ out:
 	return rc;
 }
 
-static int calc_ntlmv2_hash(struct ksmbd_session *sess, char *ntlmv2_hash,
-			    char *dname)
+static int calc_ntlmv2_hash(struct ksmbd_conn *conn, struct ksmbd_session *sess,
+			    char *ntlmv2_hash, char *dname)
 {
 	int ret, len, conv_len;
 	wchar_t *domain = NULL;
@@ -158,7 +158,7 @@ static int calc_ntlmv2_hash(struct ksmbd_session *sess, char *ntlmv2_hash,
 	}
 
 	conv_len = smb_strtoUTF16(uniname, user_name(sess->user), len,
-				  sess->conn->local_nls);
+				  conn->local_nls);
 	if (conv_len < 0 || conv_len > len) {
 		ret = -EINVAL;
 		goto out;
@@ -182,7 +182,7 @@ static int calc_ntlmv2_hash(struct ksmbd_session *sess, char *ntlmv2_hash,
 	}
 
 	conv_len = smb_strtoUTF16((__le16 *)domain, dname, len,
-				  sess->conn->local_nls);
+				  conn->local_nls);
 	if (conv_len < 0 || conv_len > len) {
 		ret = -EINVAL;
 		goto out;
@@ -215,8 +215,9 @@ out:
  *
  * 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, char *cryptkey)
+int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess,
+		      struct ntlmv2_resp *ntlmv2, int blen, char *domain_name,
+		      char *cryptkey)
 {
 	char ntlmv2_hash[CIFS_ENCPWD_SIZE];
 	char ntlmv2_rsp[CIFS_HMAC_MD5_HASH_SIZE];
@@ -230,7 +231,7 @@ int ksmbd_auth_ntlmv2(struct ksmbd_session *sess, struct ntlmv2_resp *ntlmv2,
 		return -ENOMEM;
 	}
 
-	rc = calc_ntlmv2_hash(sess, ntlmv2_hash, domain_name);
+	rc = calc_ntlmv2_hash(conn, sess, ntlmv2_hash, domain_name);
 	if (rc) {
 		ksmbd_debug(AUTH, "could not get v2 hash rc %d\n", rc);
 		goto out;
@@ -333,7 +334,8 @@ int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob,
 	/* process NTLMv2 authentication */
 	ksmbd_debug(AUTH, "decode_ntlmssp_authenticate_blob dname%s\n",
 		    domain_name);
-	ret = ksmbd_auth_ntlmv2(sess, (struct ntlmv2_resp *)((char *)authblob + nt_off),
+	ret = ksmbd_auth_ntlmv2(conn, sess,
+				(struct ntlmv2_resp *)((char *)authblob + nt_off),
 				nt_len - CIFS_ENCPWD_SIZE,
 				domain_name, conn->ntlmssp.cryptkey);
 	kfree(domain_name);
@@ -659,8 +661,9 @@ struct derivation {
 	bool binding;
 };
 
-static int generate_key(struct ksmbd_session *sess, struct kvec label,
-			struct kvec context, __u8 *key, unsigned int key_size)
+static int generate_key(struct ksmbd_conn *conn, struct ksmbd_session *sess,
+			struct kvec label, struct kvec context, __u8 *key,
+			unsigned int key_size)
 {
 	unsigned char zero = 0x0;
 	__u8 i[4] = {0, 0, 0, 1};
@@ -720,8 +723,8 @@ static int generate_key(struct ksmbd_session *sess, struct kvec label,
 		goto smb3signkey_ret;
 	}
 
-	if (sess->conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
-	    sess->conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM)
+	if (conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
+	    conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM)
 		rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), L256, 4);
 	else
 		rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), L128, 4);
@@ -756,17 +759,17 @@ static int generate_smb3signingkey(struct ksmbd_session *sess,
 	if (!chann)
 		return 0;
 
-	if (sess->conn->dialect >= SMB30_PROT_ID && signing->binding)
+	if (conn->dialect >= SMB30_PROT_ID && signing->binding)
 		key = chann->smb3signingkey;
 	else
 		key = sess->smb3signingkey;
 
-	rc = generate_key(sess, signing->label, signing->context, key,
+	rc = generate_key(conn, sess, signing->label, signing->context, key,
 			  SMB3_SIGN_KEY_SIZE);
 	if (rc)
 		return rc;
 
-	if (!(sess->conn->dialect >= SMB30_PROT_ID && signing->binding))
+	if (!(conn->dialect >= SMB30_PROT_ID && signing->binding))
 		memcpy(chann->smb3signingkey, key, SMB3_SIGN_KEY_SIZE);
 
 	ksmbd_debug(AUTH, "dumping generated AES signing keys\n");
@@ -820,30 +823,31 @@ struct derivation_twin {
 	struct derivation decryption;
 };
 
-static int generate_smb3encryptionkey(struct ksmbd_session *sess,
+static int generate_smb3encryptionkey(struct ksmbd_conn *conn,
+				      struct ksmbd_session *sess,
 				      const struct derivation_twin *ptwin)
 {
 	int rc;
 
-	rc = generate_key(sess, ptwin->encryption.label,
+	rc = generate_key(conn, sess, ptwin->encryption.label,
 			  ptwin->encryption.context, sess->smb3encryptionkey,
 			  SMB3_ENC_DEC_KEY_SIZE);
 	if (rc)
 		return rc;
 
-	rc = generate_key(sess, ptwin->decryption.label,
+	rc = generate_key(conn, sess, ptwin->decryption.label,
 			  ptwin->decryption.context,
 			  sess->smb3decryptionkey, SMB3_ENC_DEC_KEY_SIZE);
 	if (rc)
 		return rc;
 
 	ksmbd_debug(AUTH, "dumping generated AES encryption keys\n");
-	ksmbd_debug(AUTH, "Cipher type   %d\n", sess->conn->cipher_type);
+	ksmbd_debug(AUTH, "Cipher type   %d\n", conn->cipher_type);
 	ksmbd_debug(AUTH, "Session Id    %llu\n", sess->id);
 	ksmbd_debug(AUTH, "Session Key   %*ph\n",
 		    SMB2_NTLMV2_SESSKEY_SIZE, sess->sess_key);
-	if (sess->conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
-	    sess->conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM) {
+	if (conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
+	    conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM) {
 		ksmbd_debug(AUTH, "ServerIn Key  %*ph\n",
 			    SMB3_GCM256_CRYPTKEY_SIZE, sess->smb3encryptionkey);
 		ksmbd_debug(AUTH, "ServerOut Key %*ph\n",
@@ -857,7 +861,8 @@ static int generate_smb3encryptionkey(struct ksmbd_session *sess,
 	return 0;
 }
 
-int ksmbd_gen_smb30_encryptionkey(struct ksmbd_session *sess)
+int ksmbd_gen_smb30_encryptionkey(struct ksmbd_conn *conn,
+				  struct ksmbd_session *sess)
 {
 	struct derivation_twin twin;
 	struct derivation *d;
@@ -874,10 +879,11 @@ int ksmbd_gen_smb30_encryptionkey(struct ksmbd_session *sess)
 	d->context.iov_base = "ServerIn ";
 	d->context.iov_len = 10;
 
-	return generate_smb3encryptionkey(sess, &twin);
+	return generate_smb3encryptionkey(conn, sess, &twin);
 }
 
-int ksmbd_gen_smb311_encryptionkey(struct ksmbd_session *sess)
+int ksmbd_gen_smb311_encryptionkey(struct ksmbd_conn *conn,
+				   struct ksmbd_session *sess)
 {
 	struct derivation_twin twin;
 	struct derivation *d;
@@ -894,7 +900,7 @@ int ksmbd_gen_smb311_encryptionkey(struct ksmbd_session *sess)
 	d->context.iov_base = sess->Preauth_HashValue;
 	d->context.iov_len = 64;
 
-	return generate_smb3encryptionkey(sess, &twin);
+	return generate_smb3encryptionkey(conn, sess, &twin);
 }
 
 int ksmbd_gen_preauth_integrity_hash(struct ksmbd_conn *conn, char *buf,
diff --git a/fs/ksmbd/auth.h b/fs/ksmbd/auth.h
index 95629651cf26..25b772653de0 100644
--- a/fs/ksmbd/auth.h
+++ b/fs/ksmbd/auth.h
@@ -38,8 +38,9 @@ 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_ntlmv2(struct ksmbd_session *sess, struct ntlmv2_resp *ntlmv2,
-		      int blen, char *domain_name, char *cryptkey);
+int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess,
+		      struct ntlmv2_resp *ntlmv2, int blen, char *domain_name,
+		      char *cryptkey);
 int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob,
 				   int blob_len, struct ksmbd_conn *conn,
 				   struct ksmbd_session *sess);
@@ -58,8 +59,10 @@ int ksmbd_gen_smb30_signingkey(struct ksmbd_session *sess,
 			       struct ksmbd_conn *conn);
 int ksmbd_gen_smb311_signingkey(struct ksmbd_session *sess,
 				struct ksmbd_conn *conn);
-int ksmbd_gen_smb30_encryptionkey(struct ksmbd_session *sess);
-int ksmbd_gen_smb311_encryptionkey(struct ksmbd_session *sess);
+int ksmbd_gen_smb30_encryptionkey(struct ksmbd_conn *conn,
+				  struct ksmbd_session *sess);
+int ksmbd_gen_smb311_encryptionkey(struct ksmbd_conn *conn,
+				   struct ksmbd_session *sess);
 int ksmbd_gen_preauth_integrity_hash(struct ksmbd_conn *conn, char *buf,
 				     __u8 *pi_hash);
 int ksmbd_gen_sd_hash(struct ksmbd_conn *conn, char *sd_buf, int len,
diff --git a/fs/ksmbd/connection.c b/fs/ksmbd/connection.c
index e8f476c5f189..756ad631c019 100644
--- a/fs/ksmbd/connection.c
+++ b/fs/ksmbd/connection.c
@@ -36,6 +36,7 @@ void ksmbd_conn_free(struct ksmbd_conn *conn)
 	list_del(&conn->conns_list);
 	write_unlock(&conn_list_lock);
 
+	xa_destroy(&conn->sessions);
 	kvfree(conn->request_buf);
 	kfree(conn->preauth_info);
 	kfree(conn);
@@ -65,13 +66,14 @@ struct ksmbd_conn *ksmbd_conn_alloc(void)
 	conn->outstanding_credits = 0;
 
 	init_waitqueue_head(&conn->req_running_q);
+	init_waitqueue_head(&conn->r_count_q);
 	INIT_LIST_HEAD(&conn->conns_list);
-	INIT_LIST_HEAD(&conn->sessions);
 	INIT_LIST_HEAD(&conn->requests);
 	INIT_LIST_HEAD(&conn->async_requests);
 	spin_lock_init(&conn->request_lock);
 	spin_lock_init(&conn->credits_lock);
 	ida_init(&conn->async_ida);
+	xa_init(&conn->sessions);
 
 	spin_lock_init(&conn->llist_lock);
 	INIT_LIST_HEAD(&conn->lock_list);
@@ -164,7 +166,6 @@ int ksmbd_conn_write(struct ksmbd_work *work)
 	struct kvec iov[3];
 	int iov_idx = 0;
 
-	ksmbd_conn_try_dequeue_request(work);
 	if (!work->response_buf) {
 		pr_err("NULL response header\n");
 		return -EINVAL;
@@ -346,8 +347,8 @@ int ksmbd_conn_handler_loop(void *p)
 
 out:
 	/* Wait till all reference dropped to the Server object*/
-	while (atomic_read(&conn->r_count) > 0)
-		schedule_timeout(HZ);
+	wait_event(conn->r_count_q, atomic_read(&conn->r_count) == 0);
+
 
 	unload_nls(conn->local_nls);
 	if (default_conn_ops.terminate_fn)
diff --git a/fs/ksmbd/connection.h b/fs/ksmbd/connection.h
index 98c1cbe45ec9..e7f7d5707951 100644
--- a/fs/ksmbd/connection.h
+++ b/fs/ksmbd/connection.h
@@ -20,13 +20,6 @@
 
 #define KSMBD_SOCKET_BACKLOG		16
 
-/*
- * WARNING
- *
- * This is nothing but a HACK. Session status should move to channel
- * or to session. As of now we have 1 tcp_conn : 1 ksmbd_session, but
- * we need to change it to 1 tcp_conn : N ksmbd_sessions.
- */
 enum {
 	KSMBD_SESS_NEW = 0,
 	KSMBD_SESS_GOOD,
@@ -55,7 +48,7 @@ struct ksmbd_conn {
 	struct nls_table		*local_nls;
 	struct list_head		conns_list;
 	/* smb session 1 per user */
-	struct list_head		sessions;
+	struct xarray			sessions;
 	unsigned long			last_active;
 	/* How many request are running currently */
 	atomic_t			req_running;
@@ -65,6 +58,7 @@ struct ksmbd_conn {
 	unsigned int			outstanding_credits;
 	spinlock_t			credits_lock;
 	wait_queue_head_t		req_running_q;
+	wait_queue_head_t		r_count_q;
 	/* Lock to protect requests list*/
 	spinlock_t			request_lock;
 	struct list_head		requests;
diff --git a/fs/ksmbd/mgmt/share_config.c b/fs/ksmbd/mgmt/share_config.c
index cb72d30f5b71..70655af93b44 100644
--- a/fs/ksmbd/mgmt/share_config.c
+++ b/fs/ksmbd/mgmt/share_config.c
@@ -222,17 +222,3 @@ bool ksmbd_share_veto_filename(struct ksmbd_share_config *share,
 	}
 	return false;
 }
-
-void ksmbd_share_configs_cleanup(void)
-{
-	struct ksmbd_share_config *share;
-	struct hlist_node *tmp;
-	int i;
-
-	down_write(&shares_table_lock);
-	hash_for_each_safe(shares_table, i, tmp, share, hlist) {
-		hash_del(&share->hlist);
-		kill_share(share);
-	}
-	up_write(&shares_table_lock);
-}
diff --git a/fs/ksmbd/mgmt/share_config.h b/fs/ksmbd/mgmt/share_config.h
index 953befc94e84..28bf3511763f 100644
--- a/fs/ksmbd/mgmt/share_config.h
+++ b/fs/ksmbd/mgmt/share_config.h
@@ -76,6 +76,4 @@ static inline void ksmbd_share_config_put(struct ksmbd_share_config *share)
 struct ksmbd_share_config *ksmbd_share_config_get(char *name);
 bool ksmbd_share_veto_filename(struct ksmbd_share_config *share,
 			       const char *filename);
-void ksmbd_share_configs_cleanup(void);
-
 #endif /* __SHARE_CONFIG_MANAGEMENT_H__ */
diff --git a/fs/ksmbd/mgmt/tree_connect.c b/fs/ksmbd/mgmt/tree_connect.c
index 0d28e723a28c..b35ea6a6abc5 100644
--- a/fs/ksmbd/mgmt/tree_connect.c
+++ b/fs/ksmbd/mgmt/tree_connect.c
@@ -16,7 +16,8 @@
 #include "user_session.h"
 
 struct ksmbd_tree_conn_status
-ksmbd_tree_conn_connect(struct ksmbd_session *sess, char *share_name)
+ksmbd_tree_conn_connect(struct ksmbd_conn *conn, struct ksmbd_session *sess,
+			char *share_name)
 {
 	struct ksmbd_tree_conn_status status = {-EINVAL, NULL};
 	struct ksmbd_tree_connect_response *resp = NULL;
@@ -41,7 +42,7 @@ ksmbd_tree_conn_connect(struct ksmbd_session *sess, char *share_name)
 		goto out_error;
 	}
 
-	peer_addr = KSMBD_TCP_PEER_SOCKADDR(sess->conn);
+	peer_addr = KSMBD_TCP_PEER_SOCKADDR(conn);
 	resp = ksmbd_ipc_tree_connect_request(sess,
 					      sc,
 					      tree_conn,
diff --git a/fs/ksmbd/mgmt/tree_connect.h b/fs/ksmbd/mgmt/tree_connect.h
index 18e2a996e0aa..71e50271dccf 100644
--- a/fs/ksmbd/mgmt/tree_connect.h
+++ b/fs/ksmbd/mgmt/tree_connect.h
@@ -12,6 +12,7 @@
 
 struct ksmbd_share_config;
 struct ksmbd_user;
+struct ksmbd_conn;
 
 struct ksmbd_tree_connect {
 	int				id;
@@ -40,7 +41,8 @@ static inline int test_tree_conn_flag(struct ksmbd_tree_connect *tree_conn,
 struct ksmbd_session;
 
 struct ksmbd_tree_conn_status
-ksmbd_tree_conn_connect(struct ksmbd_session *sess, char *share_name);
+ksmbd_tree_conn_connect(struct ksmbd_conn *conn, struct ksmbd_session *sess,
+			char *share_name);
 
 int ksmbd_tree_conn_disconnect(struct ksmbd_session *sess,
 			       struct ksmbd_tree_connect *tree_conn);
diff --git a/fs/ksmbd/mgmt/user_session.c b/fs/ksmbd/mgmt/user_session.c
index 8d8ffd8c6f19..3fa2139a0b30 100644
--- a/fs/ksmbd/mgmt/user_session.c
+++ b/fs/ksmbd/mgmt/user_session.c
@@ -32,11 +32,13 @@ static void free_channel_list(struct ksmbd_session *sess)
 {
 	struct channel *chann, *tmp;
 
+	write_lock(&sess->chann_lock);
 	list_for_each_entry_safe(chann, tmp, &sess->ksmbd_chann_list,
 				 chann_list) {
 		list_del(&chann->chann_list);
 		kfree(chann);
 	}
+	write_unlock(&sess->chann_lock);
 }
 
 static void __session_rpc_close(struct ksmbd_session *sess,
@@ -149,11 +151,6 @@ void ksmbd_session_destroy(struct ksmbd_session *sess)
 	if (!sess)
 		return;
 
-	if (!atomic_dec_and_test(&sess->refcnt))
-		return;
-
-	list_del(&sess->sessions_entry);
-
 	down_write(&sessions_table_lock);
 	hash_del(&sess->hlist);
 	up_write(&sessions_table_lock);
@@ -181,53 +178,70 @@ static struct ksmbd_session *__session_lookup(unsigned long long id)
 	return NULL;
 }
 
-void ksmbd_session_register(struct ksmbd_conn *conn,
-			    struct ksmbd_session *sess)
+int ksmbd_session_register(struct ksmbd_conn *conn,
+			   struct ksmbd_session *sess)
 {
-	sess->conn = conn;
-	list_add(&sess->sessions_entry, &conn->sessions);
+	sess->dialect = conn->dialect;
+	memcpy(sess->ClientGUID, conn->ClientGUID, SMB2_CLIENT_GUID_SIZE);
+	return xa_err(xa_store(&conn->sessions, sess->id, sess, GFP_KERNEL));
 }
 
-void ksmbd_sessions_deregister(struct ksmbd_conn *conn)
+static int ksmbd_chann_del(struct ksmbd_conn *conn, struct ksmbd_session *sess)
 {
-	struct ksmbd_session *sess;
-
-	while (!list_empty(&conn->sessions)) {
-		sess = list_entry(conn->sessions.next,
-				  struct ksmbd_session,
-				  sessions_entry);
+	struct channel *chann, *tmp;
 
-		ksmbd_session_destroy(sess);
+	write_lock(&sess->chann_lock);
+	list_for_each_entry_safe(chann, tmp, &sess->ksmbd_chann_list,
+				 chann_list) {
+		if (chann->conn == conn) {
+			list_del(&chann->chann_list);
+			kfree(chann);
+			write_unlock(&sess->chann_lock);
+			return 0;
+		}
 	}
-}
+	write_unlock(&sess->chann_lock);
 
-static bool ksmbd_session_id_match(struct ksmbd_session *sess,
-				   unsigned long long id)
-{
-	return sess->id == id;
+	return -ENOENT;
 }
 
-struct ksmbd_session *ksmbd_session_lookup(struct ksmbd_conn *conn,
-					   unsigned long long id)
+void ksmbd_sessions_deregister(struct ksmbd_conn *conn)
 {
-	struct ksmbd_session *sess = NULL;
+	struct ksmbd_session *sess;
 
-	list_for_each_entry(sess, &conn->sessions, sessions_entry) {
-		if (ksmbd_session_id_match(sess, id))
-			return sess;
+	if (conn->binding) {
+		int bkt;
+
+		down_write(&sessions_table_lock);
+		hash_for_each(sessions_table, bkt, sess, hlist) {
+			if (!ksmbd_chann_del(conn, sess)) {
+				up_write(&sessions_table_lock);
+				goto sess_destroy;
+			}
+		}
+		up_write(&sessions_table_lock);
+	} else {
+		unsigned long id;
+
+		xa_for_each(&conn->sessions, id, sess) {
+			if (!ksmbd_chann_del(conn, sess))
+				goto sess_destroy;
+		}
 	}
-	return NULL;
-}
 
-int get_session(struct ksmbd_session *sess)
-{
-	return atomic_inc_not_zero(&sess->refcnt);
+	return;
+
+sess_destroy:
+	if (list_empty(&sess->ksmbd_chann_list)) {
+		xa_erase(&conn->sessions, sess->id);
+		ksmbd_session_destroy(sess);
+	}
 }
 
-void put_session(struct ksmbd_session *sess)
+struct ksmbd_session *ksmbd_session_lookup(struct ksmbd_conn *conn,
+					   unsigned long long id)
 {
-	if (atomic_dec_and_test(&sess->refcnt))
-		pr_err("get/%s seems to be mismatched.", __func__);
+	return xa_load(&conn->sessions, id);
 }
 
 struct ksmbd_session *ksmbd_session_lookup_slowpath(unsigned long long id)
@@ -236,10 +250,6 @@ struct ksmbd_session *ksmbd_session_lookup_slowpath(unsigned long long id)
 
 	down_read(&sessions_table_lock);
 	sess = __session_lookup(id);
-	if (sess) {
-		if (!get_session(sess))
-			sess = NULL;
-	}
 	up_read(&sessions_table_lock);
 
 	return sess;
@@ -253,6 +263,8 @@ struct ksmbd_session *ksmbd_session_lookup_all(struct ksmbd_conn *conn,
 	sess = ksmbd_session_lookup(conn, id);
 	if (!sess && conn->binding)
 		sess = ksmbd_session_lookup_slowpath(id);
+	if (sess && sess->state != SMB2_SESSION_VALID)
+		sess = NULL;
 	return sess;
 }
 
@@ -314,12 +326,11 @@ static struct ksmbd_session *__session_create(int protocol)
 		goto error;
 
 	set_session_flag(sess, protocol);
-	INIT_LIST_HEAD(&sess->sessions_entry);
 	xa_init(&sess->tree_conns);
 	INIT_LIST_HEAD(&sess->ksmbd_chann_list);
 	INIT_LIST_HEAD(&sess->rpc_handle_list);
 	sess->sequence_number = 1;
-	atomic_set(&sess->refcnt, 1);
+	rwlock_init(&sess->chann_lock);
 
 	switch (protocol) {
 	case CIFDS_SESSION_FLAG_SMB2:
diff --git a/fs/ksmbd/mgmt/user_session.h b/fs/ksmbd/mgmt/user_session.h
index e241f16a3851..8934b8ee275b 100644
--- a/fs/ksmbd/mgmt/user_session.h
+++ b/fs/ksmbd/mgmt/user_session.h
@@ -33,8 +33,10 @@ struct preauth_session {
 struct ksmbd_session {
 	u64				id;
 
+	__u16				dialect;
+	char				ClientGUID[SMB2_CLIENT_GUID_SIZE];
+
 	struct ksmbd_user		*user;
-	struct ksmbd_conn		*conn;
 	unsigned int			sequence_number;
 	unsigned int			flags;
 
@@ -48,6 +50,7 @@ struct ksmbd_session {
 	char				sess_key[CIFS_KEY_SIZE];
 
 	struct hlist_node		hlist;
+	rwlock_t			chann_lock;
 	struct list_head		ksmbd_chann_list;
 	struct xarray			tree_conns;
 	struct ida			tree_conn_ida;
@@ -57,9 +60,7 @@ struct ksmbd_session {
 	__u8				smb3decryptionkey[SMB3_ENC_DEC_KEY_SIZE];
 	__u8				smb3signingkey[SMB3_SIGN_KEY_SIZE];
 
-	struct list_head		sessions_entry;
 	struct ksmbd_file_table		file_table;
-	atomic_t			refcnt;
 };
 
 static inline int test_session_flag(struct ksmbd_session *sess, int bit)
@@ -84,8 +85,8 @@ void ksmbd_session_destroy(struct ksmbd_session *sess);
 struct ksmbd_session *ksmbd_session_lookup_slowpath(unsigned long long id);
 struct ksmbd_session *ksmbd_session_lookup(struct ksmbd_conn *conn,
 					   unsigned long long id);
-void ksmbd_session_register(struct ksmbd_conn *conn,
-			    struct ksmbd_session *sess);
+int ksmbd_session_register(struct ksmbd_conn *conn,
+			   struct ksmbd_session *sess);
 void ksmbd_sessions_deregister(struct ksmbd_conn *conn);
 struct ksmbd_session *ksmbd_session_lookup_all(struct ksmbd_conn *conn,
 					       unsigned long long id);
@@ -100,6 +101,4 @@ void ksmbd_release_tree_conn_id(struct ksmbd_session *sess, int id);
 int ksmbd_session_rpc_open(struct ksmbd_session *sess, char *rpc_name);
 void ksmbd_session_rpc_close(struct ksmbd_session *sess, int id);
 int ksmbd_session_rpc_method(struct ksmbd_session *sess, int id);
-int get_session(struct ksmbd_session *sess);
-void put_session(struct ksmbd_session *sess);
 #endif /* __USER_SESSION_MANAGEMENT_H__ */
diff --git a/fs/ksmbd/oplock.c b/fs/ksmbd/oplock.c
index 8b5560574d4c..9046cff4374b 100644
--- a/fs/ksmbd/oplock.c
+++ b/fs/ksmbd/oplock.c
@@ -30,6 +30,7 @@ static DEFINE_RWLOCK(lease_list_lock);
 static struct oplock_info *alloc_opinfo(struct ksmbd_work *work,
 					u64 id, __u16 Tid)
 {
+	struct ksmbd_conn *conn = work->conn;
 	struct ksmbd_session *sess = work->sess;
 	struct oplock_info *opinfo;
 
@@ -38,7 +39,7 @@ static struct oplock_info *alloc_opinfo(struct ksmbd_work *work,
 		return NULL;
 
 	opinfo->sess = sess;
-	opinfo->conn = sess->conn;
+	opinfo->conn = conn;
 	opinfo->level = SMB2_OPLOCK_LEVEL_NONE;
 	opinfo->op_state = OPLOCK_STATE_NONE;
 	opinfo->pending_break = 0;
@@ -615,18 +616,13 @@ static void __smb2_oplock_break_noti(struct work_struct *wk)
 	struct ksmbd_file *fp;
 
 	fp = ksmbd_lookup_durable_fd(br_info->fid);
-	if (!fp) {
-		atomic_dec(&conn->r_count);
-		ksmbd_free_work_struct(work);
-		return;
-	}
+	if (!fp)
+		goto out;
 
 	if (allocate_oplock_break_buf(work)) {
 		pr_err("smb2_allocate_rsp_buf failed! ");
-		atomic_dec(&conn->r_count);
 		ksmbd_fd_put(work, fp);
-		ksmbd_free_work_struct(work);
-		return;
+		goto out;
 	}
 
 	rsp_hdr = smb2_get_msg(work->response_buf);
@@ -667,8 +663,16 @@ static void __smb2_oplock_break_noti(struct work_struct *wk)
 
 	ksmbd_fd_put(work, fp);
 	ksmbd_conn_write(work);
+
+out:
 	ksmbd_free_work_struct(work);
-	atomic_dec(&conn->r_count);
+	/*
+	 * Checking waitqueue to dropping pending requests on
+	 * disconnection. waitqueue_active is safe because it
+	 * uses atomic operation for condition.
+	 */
+	if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q))
+		wake_up(&conn->r_count_q);
 }
 
 /**
@@ -731,9 +735,7 @@ static void __smb2_lease_break_noti(struct work_struct *wk)
 
 	if (allocate_oplock_break_buf(work)) {
 		ksmbd_debug(OPLOCK, "smb2_allocate_rsp_buf failed! ");
-		ksmbd_free_work_struct(work);
-		atomic_dec(&conn->r_count);
-		return;
+		goto out;
 	}
 
 	rsp_hdr = smb2_get_msg(work->response_buf);
@@ -771,8 +773,16 @@ static void __smb2_lease_break_noti(struct work_struct *wk)
 	inc_rfc1001_len(work->response_buf, 44);
 
 	ksmbd_conn_write(work);
+
+out:
 	ksmbd_free_work_struct(work);
-	atomic_dec(&conn->r_count);
+	/*
+	 * Checking waitqueue to dropping pending requests on
+	 * disconnection. waitqueue_active is safe because it
+	 * uses atomic operation for condition.
+	 */
+	if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q))
+		wake_up(&conn->r_count_q);
 }
 
 /**
@@ -972,7 +982,7 @@ int find_same_lease_key(struct ksmbd_session *sess, struct ksmbd_inode *ci,
 	}
 
 	list_for_each_entry(lb, &lease_table_list, l_entry) {
-		if (!memcmp(lb->client_guid, sess->conn->ClientGUID,
+		if (!memcmp(lb->client_guid, sess->ClientGUID,
 			    SMB2_CLIENT_GUID_SIZE))
 			goto found;
 	}
@@ -988,7 +998,7 @@ found:
 		rcu_read_unlock();
 		if (opinfo->o_fp->f_ci == ci)
 			goto op_next;
-		err = compare_guid_key(opinfo, sess->conn->ClientGUID,
+		err = compare_guid_key(opinfo, sess->ClientGUID,
 				       lctx->lease_key);
 		if (err) {
 			err = -EINVAL;
@@ -1122,7 +1132,7 @@ int smb_grant_oplock(struct ksmbd_work *work, int req_op_level, u64 pid,
 		struct oplock_info *m_opinfo;
 
 		/* is lease already granted ? */
-		m_opinfo = same_client_has_lease(ci, sess->conn->ClientGUID,
+		m_opinfo = same_client_has_lease(ci, sess->ClientGUID,
 						 lctx);
 		if (m_opinfo) {
 			copy_lease(m_opinfo, opinfo);
@@ -1240,7 +1250,7 @@ void smb_break_all_levII_oplock(struct ksmbd_work *work, struct ksmbd_file *fp,
 {
 	struct oplock_info *op, *brk_op;
 	struct ksmbd_inode *ci;
-	struct ksmbd_conn *conn = work->sess->conn;
+	struct ksmbd_conn *conn = work->conn;
 
 	if (!test_share_config_flag(work->tcon->share_conf,
 				    KSMBD_SHARE_FLAG_OPLOCKS))
diff --git a/fs/ksmbd/server.c b/fs/ksmbd/server.c
index 4cd03d661df0..ce42bff42ef9 100644
--- a/fs/ksmbd/server.c
+++ b/fs/ksmbd/server.c
@@ -261,7 +261,13 @@ static void handle_ksmbd_work(struct work_struct *wk)
 
 	ksmbd_conn_try_dequeue_request(work);
 	ksmbd_free_work_struct(work);
-	atomic_dec(&conn->r_count);
+	/*
+	 * Checking waitqueue to dropping pending requests on
+	 * disconnection. waitqueue_active is safe because it
+	 * uses atomic operation for condition.
+	 */
+	if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q))
+		wake_up(&conn->r_count_q);
 }
 
 /**
diff --git a/fs/ksmbd/smb2misc.c b/fs/ksmbd/smb2misc.c
index f8f456377a51..6e25ace36568 100644
--- a/fs/ksmbd/smb2misc.c
+++ b/fs/ksmbd/smb2misc.c
@@ -90,11 +90,6 @@ static int smb2_get_data_area_len(unsigned int *off, unsigned int *len,
 	*off = 0;
 	*len = 0;
 
-	/* error reqeusts do not have data area */
-	if (hdr->Status && hdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
-	    (((struct smb2_err_rsp *)hdr)->StructureSize) == SMB2_ERROR_STRUCTURE_SIZE2_LE)
-		return ret;
-
 	/*
 	 * Following commands have data areas so we have to get the location
 	 * of the data buffer offset and data buffer length for the particular
@@ -136,8 +131,11 @@ static int smb2_get_data_area_len(unsigned int *off, unsigned int *len,
 		*len = le16_to_cpu(((struct smb2_read_req *)hdr)->ReadChannelInfoLength);
 		break;
 	case SMB2_WRITE:
-		if (((struct smb2_write_req *)hdr)->DataOffset) {
-			*off = le16_to_cpu(((struct smb2_write_req *)hdr)->DataOffset);
+		if (((struct smb2_write_req *)hdr)->DataOffset ||
+		    ((struct smb2_write_req *)hdr)->Length) {
+			*off = max_t(unsigned int,
+				     le16_to_cpu(((struct smb2_write_req *)hdr)->DataOffset),
+				     offsetof(struct smb2_write_req, Buffer));
 			*len = le32_to_cpu(((struct smb2_write_req *)hdr)->Length);
 			break;
 		}
diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index 353f047e783c..9751cc92c111 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -535,9 +535,10 @@ int smb2_allocate_rsp_buf(struct ksmbd_work *work)
 		struct smb2_query_info_req *req;
 
 		req = smb2_get_msg(work->request_buf);
-		if (req->InfoType == SMB2_O_INFO_FILE &&
-		    (req->FileInfoClass == FILE_FULL_EA_INFORMATION ||
-		     req->FileInfoClass == FILE_ALL_INFORMATION))
+		if ((req->InfoType == SMB2_O_INFO_FILE &&
+		     (req->FileInfoClass == FILE_FULL_EA_INFORMATION ||
+		     req->FileInfoClass == FILE_ALL_INFORMATION)) ||
+		    req->InfoType == SMB2_O_INFO_SECURITY)
 			sz = large_sz;
 	}
 
@@ -588,10 +589,12 @@ int smb2_check_user_session(struct ksmbd_work *work)
 	return -EINVAL;
 }
 
-static void destroy_previous_session(struct ksmbd_user *user, u64 id)
+static void destroy_previous_session(struct ksmbd_conn *conn,
+				     struct ksmbd_user *user, u64 id)
 {
 	struct ksmbd_session *prev_sess = ksmbd_session_lookup_slowpath(id);
 	struct ksmbd_user *prev_user;
+	struct channel *chann;
 
 	if (!prev_sess)
 		return;
@@ -601,13 +604,14 @@ static void destroy_previous_session(struct ksmbd_user *user, u64 id)
 	if (!prev_user ||
 	    strcmp(user->name, prev_user->name) ||
 	    user->passkey_sz != prev_user->passkey_sz ||
-	    memcmp(user->passkey, prev_user->passkey, user->passkey_sz)) {
-		put_session(prev_sess);
+	    memcmp(user->passkey, prev_user->passkey, user->passkey_sz))