1 files changed, 56 insertions, 44 deletions

diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
index 57c2a7df3457..3052a208c6ca 100644
--- a/fs/smb/client/connect.c
+++ b/fs/smb/client/connect.c
@@ -216,22 +216,29 @@ cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server,
 	/* If server is a channel, select the primary channel */
 	pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
 
+	/*
+	 * if the server has been marked for termination, there is a
+	 * chance that the remaining channels all need reconnect. To be
+	 * on the safer side, mark the session and trees for reconnect
+	 * for this scenario. This might cause a few redundant session
+	 * setup and tree connect requests, but it is better than not doing
+	 * a tree connect when needed, and all following requests failing
+	 */
+	if (server->terminate) {
+		mark_smb_session = true;
+		server = pserver;
+	}
 
 	spin_lock(&cifs_tcp_ses_lock);
 	list_for_each_entry_safe(ses, nses, &pserver->smb_ses_list, smb_ses_list) {
-		/*
-		 * if channel has been marked for termination, nothing to do
-		 * for the channel. in fact, we cannot find the channel for the
-		 * server. So safe to exit here
-		 */
-		if (server->terminate)
-			break;
-
 		/* check if iface is still active */
-		if (!cifs_chan_is_iface_active(ses, server))
+		spin_lock(&ses->chan_lock);
+		if (!cifs_chan_is_iface_active(ses, server)) {
+			spin_unlock(&ses->chan_lock);
 			cifs_chan_update_iface(ses, server);
+			spin_lock(&ses->chan_lock);
+		}
 
-		spin_lock(&ses->chan_lock);
 		if (!mark_smb_session && cifs_chan_needs_reconnect(ses, server)) {
 			spin_unlock(&ses->chan_lock);
 			continue;
@@ -402,13 +409,7 @@ static int __cifs_reconnect(struct TCP_Server_Info *server,
 			spin_unlock(&server->srv_lock);
 			cifs_swn_reset_server_dstaddr(server);
 			cifs_server_unlock(server);
-
-			/* increase ref count which reconnect work will drop */
-			spin_lock(&cifs_tcp_ses_lock);
-			server->srv_count++;
-			spin_unlock(&cifs_tcp_ses_lock);
-			if (mod_delayed_work(cifsiod_wq, &server->reconnect, 0))
-				cifs_put_tcp_session(server, false);
+			mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
 		}
 	} while (server->tcpStatus == CifsNeedReconnect);
 
@@ -482,6 +483,7 @@ static int reconnect_target_unlocked(struct TCP_Server_Info *server, struct dfs_
 static int reconnect_dfs_server(struct TCP_Server_Info *server)
 {
 	struct dfs_cache_tgt_iterator *target_hint = NULL;
+
 	DFS_CACHE_TGT_LIST(tl);
 	int num_targets = 0;
 	int rc = 0;
@@ -538,13 +540,7 @@ static int reconnect_dfs_server(struct TCP_Server_Info *server)
 		spin_unlock(&server->srv_lock);
 		cifs_swn_reset_server_dstaddr(server);
 		cifs_server_unlock(server);
-
-		/* increase ref count which reconnect work will drop */
-		spin_lock(&cifs_tcp_ses_lock);
-		server->srv_count++;
-		spin_unlock(&cifs_tcp_ses_lock);
-		if (mod_delayed_work(cifsiod_wq, &server->reconnect, 0))
-			cifs_put_tcp_session(server, false);
+		mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
 	} while (server->tcpStatus == CifsNeedReconnect);
 
 	mutex_lock(&server->refpath_lock);
@@ -750,6 +746,7 @@ cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
 {
 	struct msghdr smb_msg = {};
 	struct kvec iov = {.iov_base = buf, .iov_len = to_read};
+
 	iov_iter_kvec(&smb_msg.msg_iter, ITER_DEST, &iov, 1, to_read);
 
 	return cifs_readv_from_socket(server, &smb_msg);
@@ -1213,7 +1210,12 @@ next_pdu:
 		server->total_read += length;
 
 		if (server->ops->next_header) {
-			next_offset = server->ops->next_header(buf);
+			if (server->ops->next_header(server, buf, &next_offset)) {
+				cifs_dbg(VFS, "%s: malformed response (next_offset=%u)\n",
+					 __func__, next_offset);
+				cifs_reconnect(server, true);
+				continue;
+			}
 			if (next_offset)
 				server->pdu_size = next_offset;
 		}
@@ -1400,11 +1402,13 @@ cifs_match_ipaddr(struct sockaddr *srcaddr, struct sockaddr *rhs)
 	case AF_INET: {
 		struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
 		struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
+
 		return (saddr4->sin_addr.s_addr == vaddr4->sin_addr.s_addr);
 	}
 	case AF_INET6: {
 		struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
 		struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
+
 		return (ipv6_addr_equal(&saddr6->sin6_addr, &vaddr6->sin6_addr)
 			&& saddr6->sin6_scope_id == vaddr6->sin6_scope_id);
 	}
@@ -1620,25 +1624,22 @@ cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
 	list_del_init(&server->tcp_ses_list);
 	spin_unlock(&cifs_tcp_ses_lock);
 
-	/* For secondary channels, we pick up ref-count on the primary server */
-	if (SERVER_IS_CHAN(server))
-		cifs_put_tcp_session(server->primary_server, from_reconnect);
-
 	cancel_delayed_work_sync(&server->echo);
 
-	if (from_reconnect) {
+	if (from_reconnect)
 		/*
 		 * Avoid deadlock here: reconnect work calls
 		 * cifs_put_tcp_session() at its end. Need to be sure
 		 * that reconnect work does nothing with server pointer after
 		 * that step.
 		 */
-		if (cancel_delayed_work(&server->reconnect))
-			cifs_put_tcp_session(server, from_reconnect);
-	} else {
-		if (cancel_delayed_work_sync(&server->reconnect))
-			cifs_put_tcp_session(server, from_reconnect);
-	}
+		cancel_delayed_work(&server->reconnect);
+	else
+		cancel_delayed_work_sync(&server->reconnect);
+
+	/* For secondary channels, we pick up ref-count on the primary server */
+	if (SERVER_IS_CHAN(server))
+		cifs_put_tcp_session(server->primary_server, from_reconnect);
 
 	spin_lock(&server->srv_lock);
 	server->tcpStatus = CifsExiting;
@@ -2065,6 +2066,12 @@ void __cifs_put_smb_ses(struct cifs_ses *ses)
 		ses->chans[i].server = NULL;
 	}
 
+	/* we now account for primary channel in iface->refcount */
+	if (ses->chans[0].iface) {
+		kref_put(&ses->chans[0].iface->refcount, release_iface);
+		ses->chans[0].server = NULL;
+	}
+
 	sesInfoFree(ses);
 	cifs_put_tcp_session(server, 0);
 }
@@ -2596,8 +2603,8 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
 			rc = -EOPNOTSUPP;
 			goto out_fail;
 		} else {
-			cifs_dbg(VFS, "Check vers= mount option. SMB3.11 "
-				"disabled but required for POSIX extensions\n");
+			cifs_dbg(VFS,
+				"Check vers= mount option. SMB3.11 disabled but required for POSIX extensions\n");
 			rc = -EOPNOTSUPP;
 			goto out_fail;
 		}
@@ -2740,7 +2747,6 @@ cifs_put_tlink(struct tcon_link *tlink)
 	if (!IS_ERR(tlink_tcon(tlink)))
 		cifs_put_tcon(tlink_tcon(tlink));
 	kfree(tlink);
-	return;
 }
 
 static int
@@ -2881,6 +2887,7 @@ static inline void
 cifs_reclassify_socket4(struct socket *sock)
 {
 	struct sock *sk = sock->sk;
+
 	BUG_ON(!sock_allow_reclassification(sk));
 	sock_lock_init_class_and_name(sk, "slock-AF_INET-CIFS",
 		&cifs_slock_key[0], "sk_lock-AF_INET-CIFS", &cifs_key[0]);
@@ -2890,6 +2897,7 @@ static inline void
 cifs_reclassify_socket6(struct socket *sock)
 {
 	struct sock *sk = sock->sk;
+
 	BUG_ON(!sock_allow_reclassification(sk));
 	sock_lock_init_class_and_name(sk, "slock-AF_INET6-CIFS",
 		&cifs_slock_key[1], "sk_lock-AF_INET6-CIFS", &cifs_key[1]);
@@ -2924,15 +2932,18 @@ static int
 bind_socket(struct TCP_Server_Info *server)
 {
 	int rc = 0;
+
 	if (server->srcaddr.ss_family != AF_UNSPEC) {
 		/* Bind to the specified local IP address */
 		struct socket *socket = server->ssocket;
+
 		rc = kernel_bind(socket,
 				 (struct sockaddr *) &server->srcaddr,
 				 sizeof(server->srcaddr));
 		if (rc < 0) {
 			struct sockaddr_in *saddr4;
 			struct sockaddr_in6 *saddr6;
+
 			saddr4 = (struct sockaddr_in *)&server->srcaddr;
 			saddr6 = (struct sockaddr_in6 *)&server->srcaddr;
 			if (saddr6->sin6_family == AF_INET6)
@@ -3162,6 +3173,7 @@ void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
 
 	if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
 		__u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
+
 		cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
 		/*
 		 * check for reconnect case in which we do not
@@ -3665,7 +3677,7 @@ CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
 	smb_buffer_response = smb_buffer;
 
 	header_assemble(smb_buffer, SMB_COM_TREE_CONNECT_ANDX,
-			NULL /*no tid */ , 4 /*wct */ );
+			NULL /*no tid */, 4 /*wct */);
 
 	smb_buffer->Mid = get_next_mid(ses->server);
 	smb_buffer->Uid = ses->Suid;
@@ -3684,12 +3696,12 @@ CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
 	if (ses->server->sign)
 		smb_buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
 
-	if (ses->capabilities & CAP_STATUS32) {
+	if (ses->capabilities & CAP_STATUS32)
 		smb_buffer->Flags2 |= SMBFLG2_ERR_STATUS;
-	}
-	if (ses->capabilities & CAP_DFS) {
+
+	if (ses->capabilities & CAP_DFS)
 		smb_buffer->Flags2 |= SMBFLG2_DFS;
-	}
+
 	if (ses->capabilities & CAP_UNICODE) {
 		smb_buffer->Flags2 |= SMBFLG2_UNICODE;
 		length =