Merge tag '5.18-rc2-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:

 - two fixes related to unmount

 - symlink overflow fix

 - minor netfs fix

 - improved tracing for crediting (flow control)

* tag '5.18-rc2-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: verify that tcon is valid before dereference in cifs_kill_sb
  cifs: potential buffer overflow in handling symlinks
  cifs: Split the smb3_add_credits tracepoint
  cifs: release cached dentries only if mount is complete
  cifs: Check the IOCB_DIRECT flag, not O_DIRECT

fs/cifs/cifsfs.c

@@ -266,13 +266,11 @@ static void cifs_kill_sb(struct super_block *sb)
 	 * before we kill the sb.
 	 */
 	if (cifs_sb->root) {
-		dput(cifs_sb->root);
-		cifs_sb->root = NULL;
-	}
-	node = rb_first(root);
-	while (node != NULL) {
+		for (node = rb_first(root); node; node = rb_next(node)) {
 			tlink = rb_entry(node, struct tcon_link, tl_rbnode);
 			tcon = tlink_tcon(tlink);
+			if (IS_ERR(tcon))
+				continue;
 			cfid = &tcon->crfid;
 			mutex_lock(&cfid->fid_mutex);
 			if (cfid->dentry) {
@@ -280,7 +278,11 @@ static void cifs_kill_sb(struct super_block *sb)
 				cfid->dentry = NULL;
 			}
 			mutex_unlock(&cfid->fid_mutex);
-		node = rb_next(node);
+		}
+
+		/* finally release root dentry */
+		dput(cifs_sb->root);
+		cifs_sb->root = NULL;
 	}
 
 	kill_anon_super(sb);
@@ -944,7 +946,7 @@ cifs_loose_read_iter(struct kiocb *iocb, struct iov_iter *iter)
 	ssize_t rc;
 	struct inode *inode = file_inode(iocb->ki_filp);
 
-	if (iocb->ki_filp->f_flags & O_DIRECT)
+	if (iocb->ki_flags & IOCB_DIRECT)
 		return cifs_user_readv(iocb, iter);
 
 	rc = cifs_revalidate_mapping(inode);

fs/cifs/connect.c

@@ -1049,7 +1049,7 @@ smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
 		spin_unlock(&server->req_lock);
 		wake_up(&server->request_q);
 
-		trace_smb3_add_credits(server->CurrentMid,
+		trace_smb3_hdr_credits(server->CurrentMid,
 				server->conn_id, server->hostname, scredits,
 				le16_to_cpu(shdr->CreditRequest), in_flight);
 		cifs_server_dbg(FYI, "%s: added %u credits total=%d\n",

fs/cifs/link.c

@@ -85,6 +85,9 @@ parse_mf_symlink(const u8 *buf, unsigned int buf_len, unsigned int *_link_len,
 	if (rc != 1)
 		return -EINVAL;
 
+	if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
+		return -EINVAL;
+
 	rc = symlink_hash(link_len, link_str, md5_hash);
 	if (rc) {
 		cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);

fs/cifs/smb2ops.c

@@ -86,6 +86,9 @@ smb2_add_credits(struct TCP_Server_Info *server,
 	if (*val > 65000) {
 		*val = 65000; /* Don't get near 64K credits, avoid srv bugs */
 		pr_warn_once("server overflowed SMB3 credits\n");
+		trace_smb3_overflow_credits(server->CurrentMid,
+					    server->conn_id, server->hostname, *val,
+					    add, server->in_flight);
 	}
 	server->in_flight--;
 	if (server->in_flight == 0 &&
@@ -251,7 +254,7 @@ smb2_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size,
 	in_flight = server->in_flight;
 	spin_unlock(&server->req_lock);
 
-	trace_smb3_add_credits(server->CurrentMid,
+	trace_smb3_wait_credits(server->CurrentMid,
 			server->conn_id, server->hostname, scredits, -(credits->value), in_flight);
 	cifs_dbg(FYI, "%s: removed %u credits total=%d\n",
 			__func__, credits->value, scredits);
@@ -300,7 +303,7 @@ smb2_adjust_credits(struct TCP_Server_Info *server,
 	spin_unlock(&server->req_lock);
 	wake_up(&server->request_q);
 
-	trace_smb3_add_credits(server->CurrentMid,
+	trace_smb3_adj_credits(server->CurrentMid,
 			server->conn_id, server->hostname, scredits,
 			credits->value - new_val, in_flight);
 	cifs_dbg(FYI, "%s: adjust added %u credits total=%d\n",
@@ -2492,7 +2495,7 @@ smb2_is_status_pending(char *buf, struct TCP_Server_Info *server)
 		spin_unlock(&server->req_lock);
 		wake_up(&server->request_q);
 
-		trace_smb3_add_credits(server->CurrentMid,
+		trace_smb3_pend_credits(server->CurrentMid,
 				server->conn_id, server->hostname, scredits,
 				le16_to_cpu(shdr->CreditRequest), in_flight);
 		cifs_dbg(FYI, "%s: status pending add %u credits total=%d\n",

fs/cifs/trace.h

@@ -1006,6 +1006,13 @@ DEFINE_SMB3_CREDIT_EVENT(credit_timeout);
 DEFINE_SMB3_CREDIT_EVENT(insufficient_credits);
 DEFINE_SMB3_CREDIT_EVENT(too_many_credits);
 DEFINE_SMB3_CREDIT_EVENT(add_credits);
+DEFINE_SMB3_CREDIT_EVENT(adj_credits);
+DEFINE_SMB3_CREDIT_EVENT(hdr_credits);
+DEFINE_SMB3_CREDIT_EVENT(nblk_credits);
+DEFINE_SMB3_CREDIT_EVENT(pend_credits);
+DEFINE_SMB3_CREDIT_EVENT(wait_credits);
+DEFINE_SMB3_CREDIT_EVENT(waitff_credits);
+DEFINE_SMB3_CREDIT_EVENT(overflow_credits);
 DEFINE_SMB3_CREDIT_EVENT(set_credits);
 
 #endif /* _CIFS_TRACE_H */

fs/cifs/transport.c

@@ -542,7 +542,7 @@ wait_for_free_credits(struct TCP_Server_Info *server, const int num_credits,
 		in_flight = server->in_flight;
 		spin_unlock(&server->req_lock);
 
-		trace_smb3_add_credits(server->CurrentMid,
+		trace_smb3_nblk_credits(server->CurrentMid,
 				server->conn_id, server->hostname, scredits, -1, in_flight);
 		cifs_dbg(FYI, "%s: remove %u credits total=%d\n",
 				__func__, 1, scredits);
@@ -648,7 +648,7 @@ wait_for_free_credits(struct TCP_Server_Info *server, const int num_credits,
 			in_flight = server->in_flight;
 			spin_unlock(&server->req_lock);
 
-			trace_smb3_add_credits(server->CurrentMid,
+			trace_smb3_waitff_credits(server->CurrentMid,
 					server->conn_id, server->hostname, scredits,
 					-(num_credits), in_flight);
 			cifs_dbg(FYI, "%s: remove %u credits total=%d\n",