Ignore --protect-args when already sent by client

In parse_arguments when --protect-args is encountered the function exits
early. The caller is expected to check protect_args, and recall
parse_arguments setting protect_args to 2. This patch prevents the
client from resetting protect_args during the second pass of
parse_arguments. This prevents parse_arguments returning early the
second time before it's able to sanitize the arguments it received.

int parse_arguments(int *argc_p, const char ***argv_p)
{
	static poptContext pc;
	char *ref = lp_refuse_options(module_id);
	const char *arg, **argv = *argv_p;
	int argc = *argc_p;
	int opt;
	int orig_protect_args = protect_args;

	if (ref && *ref)
		set_refuse_options(ref);
	if (am_daemon) {
		set_refuse_options("log-file*");
#ifdef ICONV_OPTION
		if (!*lp_charset(module_id))
			set_refuse_options("iconv");
#endif
	}

#ifdef ICONV_OPTION
	if (!am_daemon && protect_args <= 0 && (arg = getenv("RSYNC_ICONV")) != NULL && *arg)
		iconv_opt = strdup(arg);
#endif

	/* TODO: Call poptReadDefaultConfig; handle errors. */

	/* The context leaks in case of an error, but if there's a
	 * problem we always exit anyhow. */
	if (pc)
		poptFreeContext(pc);
	pc = poptGetContext(RSYNC_NAME, argc, argv, long_options, 0);
	if (!am_server) {
		poptReadDefaultConfig(pc, 0);
		popt_unalias(pc, "--daemon");
		popt_unalias(pc, "--server");
	}

	while ((opt = poptGetNextOpt(pc)) != -1) {
		/* most options are handled automatically by popt;
		 * only special cases are returned and listed here. */

		switch (opt) {
		case OPT_VERSION:
			print_rsync_version(FINFO);
			exit_cleanup(0);

		case OPT_SERVER:
			if (!am_server) {
				/* Disable popt aliases on the server side and
				 * then start parsing the options again. */
				poptFreeContext(pc);
				pc = poptGetContext(RSYNC_NAME, argc, argv,
						    long_options, 0);
				am_server = 1;
			}
#ifdef ICONV_OPTION
			iconv_opt = NULL;
#endif
			break;

		case OPT_SENDER:
			if (!am_server) {
				usage(FERROR);
				exit_cleanup(RERR_SYNTAX);
			}
			am_sender = 1;
			break;

		case OPT_DAEMON:
			if (am_daemon) {
				strlcpy(err_buf,
					"Attempt to hack rsync thwarted!\n",
					sizeof err_buf);
				return 0;
			}
#ifdef ICONV_OPTION
			iconv_opt = NULL;
#endif
			protect_args = 0;
			poptFreeContext(pc);
			pc = poptGetContext(RSYNC_NAME, argc, argv,
					    long_daemon_options, 0);
			while ((opt = poptGetNextOpt(pc)) != -1) {
				char **cpp;
				switch (opt) {
				case 'h':
					daemon_usage(FINFO);
					exit_cleanup(0);

				case 'M':
					arg = poptGetOptArg(pc);
					if (!strchr(arg, '=')) {
						rprintf(FERROR,
						    "--dparam value is missing an '=': %s\n",
						    arg);
						goto daemon_error;
					}
					cpp = EXPAND_ITEM_LIST(&dparam_list, char *, 4);
					*cpp = strdup(arg);
					break;

				case 'v':
					verbose++;
					break;

				default:
					rprintf(FERROR,
					    "rsync: %s: %s (in daemon mode)\n",
					    poptBadOption(pc, POPT_BADOPTION_NOALIAS),
					    poptStrerror(opt));
					goto daemon_error;
				}
			}

			if (dparam_list.count && !set_dparams(1))
				exit_cleanup(RERR_SYNTAX);

			if (tmpdir && strlen(tmpdir) >= MAXPATHLEN - 10) {
				snprintf(err_buf, sizeof err_buf,
					 "the --temp-dir path is WAY too long.\n");
				return 0;
			}

			if (!daemon_opt) {
				rprintf(FERROR, "Daemon option(s) used without --daemon.\n");
			    daemon_error:
				rprintf(FERROR,
				    "(Type \"rsync --daemon --help\" for assistance with daemon mode.)\n");
				exit_cleanup(RERR_SYNTAX);
			}

			*argv_p = argv = poptGetArgs(pc);
			*argc_p = argc = count_args(argv);
			am_starting_up = 0;
			daemon_opt = 0;
			am_daemon = 1;
			return 1;

		case OPT_MODIFY_WINDOW:
			/* The value has already been set by popt, but
			 * we need to remember that we're using a
			 * non-default setting. */
			modify_window_set = 1;
			break;

		case OPT_FILTER:
			parse_filter_str(&filter_list, poptGetOptArg(pc),
					rule_template(0), 0);
			break;

		case OPT_EXCLUDE:
			parse_filter_str(&filter_list, poptGetOptArg(pc),
					rule_template(0), XFLG_OLD_PREFIXES);
			break;

		case OPT_INCLUDE:
			parse_filter_str(&filter_list, poptGetOptArg(pc),
					rule_template(FILTRULE_INCLUDE), XFLG_OLD_PREFIXES);
			break;

		case OPT_EXCLUDE_FROM:
		case OPT_INCLUDE_FROM:
			arg = poptGetOptArg(pc);
			if (sanitize_paths)
				arg = sanitize_path(NULL, arg, NULL, 0, SP_DEFAULT);
			if (daemon_filter_list.head) {
				int rej;
				char *cp = strdup(arg);
				if (!cp)
					out_of_memory("parse_arguments");
				if (!*cp)
					rej = 1;
				else {
					char *dir = cp + (*cp == '/' ? module_dirlen : 0);
					clean_fname(dir, CFN_COLLAPSE_DOT_DOT_DIRS);
					rej = check_filter(&daemon_filter_list, FLOG, dir, 0) < 0;
				}
				free(cp);
				if (rej)
					goto options_rejected;
			}
			parse_filter_file(&filter_list, arg,
				rule_template(opt == OPT_INCLUDE_FROM ? FILTRULE_INCLUDE : 0),
				XFLG_FATAL_ERRORS | XFLG_OLD_PREFIXES);
			break;

		case 'a':
			if (refused_archive_part) {
				create_refuse_error(refused_archive_part);
				return 0;
			}
			if (!recurse) /* preserve recurse == 2 */
				recurse = 1;
#ifdef SUPPORT_LINKS
			preserve_links = 1;
#endif
			preserve_perms = 1;
			preserve_times = 1;
			preserve_gid = 1;
			preserve_uid = 1;
			preserve_devices = 1;
			preserve_specials = 1;
			break;

		case 'D':
			preserve_devices = preserve_specials = 1;
			break;

		case OPT_NO_D:
			preserve_devices = preserve_specials = 0;
			break;

		case 'h':
			human_readable++;
			break;

		case 'H':
			preserve_hard_links++;
			break;

		case 'i':
			itemize_changes++;
			break;

		case 'v':
			verbose++;
			break;

		case 'y':
			fuzzy_basis++;
			break;

		case 'q':
			quiet++;
			break;

		case 'x':
			one_file_system++;
			break;

		case 'F':
			switch (++F_option_cnt) {
			case 1:
				parse_filter_str(&filter_list,": /.rsync-filter",rule_template(0),0);
				break;
			case 2:
				parse_filter_str(&filter_list,"- .rsync-filter",rule_template(0),0);
				break;
			}
			break;

		case 'P':
			if (refused_partial || refused_progress) {
				create_refuse_error(refused_partial
				    ? refused_partial : refused_progress);
				return 0;
			}
			do_progress = 1;
			keep_partial = 1;
			break;

		case 'z':
			do_compression++;
			break;

		case 'M':
			arg = poptGetOptArg(pc);
			if (*arg != '-') {
				snprintf(err_buf, sizeof err_buf,
					"Remote option must start with a dash: %s\n", arg);
				return 0;
			}
			if (remote_option_cnt+2 >= remote_option_alloc) {
				remote_option_alloc += 16;
				remote_options = realloc_array(remote_options,
							const char *, remote_option_alloc);
				if (!remote_options)
					out_of_memory("parse_arguments");
				if (!remote_option_cnt)
					remote_options[0] = "ARG0";
			}
			remote_options[++remote_option_cnt] = arg;
			remote_options[remote_option_cnt+1] = NULL;
			break;

		case OPT_WRITE_BATCH:
			/* batch_name is already set */
			write_batch = 1;
			break;

		case OPT_ONLY_WRITE_BATCH:
			/* batch_name is already set */
			write_batch = -1;
			break;

		case OPT_READ_BATCH:
			/* batch_name is already set */
			read_batch = 1;
			break;

		case OPT_NO_ICONV:
#ifdef ICONV_OPTION
			iconv_opt = NULL;
#endif
			break;

		case OPT_MAX_SIZE:
			if ((max_size = parse_size_arg(&max_size_arg, 'b')) < 0) {
				snprintf(err_buf, sizeof err_buf,
					"--max-size value is invalid: %s\n",
					max_size_arg);
				return 0;
			}
			break;

		case OPT_MIN_SIZE:
			if ((min_size = parse_size_arg(&min_size_arg, 'b')) < 0) {
				snprintf(err_buf, sizeof err_buf,
					"--min-size value is invalid: %s\n",
					min_size_arg);
				return 0;
			}
			break;

		case OPT_BWLIMIT:
			{
				OFF_T limit = parse_size_arg(&bwlimit_arg, 'K');
				if (limit < 0) {
					snprintf(err_buf, sizeof err_buf,
						"--bwlimit value is invalid: %s\n", bwlimit_arg);
					return 0;
				}
				bwlimit = (limit + 512) / 1024;
				if (limit && !bwlimit) {
					snprintf(err_buf, sizeof err_buf,
						"--bwlimit value is too small: %s\n", bwlimit_arg);
					return 0;
				}
			}
			break;

		case OPT_APPEND:
			if (am_server)
				append_mode++;
			else
				append_mode = 1;
			break;

		case OPT_LINK_DEST:
#ifdef SUPPORT_HARD_LINKS
			link_dest = 1;
			dest_option = "--link-dest";
			goto set_dest_dir;
#else
			snprintf(err_buf, sizeof err_buf,
				 "hard links are not supported on this %s\n",
				 am_server ? "server" : "client");
			return 0;
#endif

		case OPT_COPY_DEST:
			copy_dest = 1;
			dest_option = "--copy-dest";
			goto set_dest_dir;

		case OPT_COMPARE_DEST:
			compare_dest = 1;
			dest_option = "--compare-dest";
		set_dest_dir:
			if (basis_dir_cnt >= MAX_BASIS_DIRS) {
				snprintf(err_buf, sizeof err_buf,
					"ERROR: at most %d %s args may be specified\n",
					MAX_BASIS_DIRS, dest_option);
				return 0;
			}
			/* We defer sanitizing this arg until we know what
			 * our destination directory is going to be. */
			basis_dir[basis_dir_cnt++] = (char *)poptGetOptArg(pc);
			break;

		case OPT_CHMOD:
			arg = poptGetOptArg(pc);
			if (!parse_chmod(arg, &chmod_modes)) {
				snprintf(err_buf, sizeof err_buf,
				    "Invalid argument passed to --chmod (%s)\n",
				    arg);
				return 0;
			}
			break;

		case OPT_INFO:
			arg = poptGetOptArg(pc);
			parse_output_words(info_words, info_levels, arg, USER_PRIORITY);
			break;

		case OPT_DEBUG:
			arg = poptGetOptArg(pc);
			parse_output_words(debug_words, debug_levels, arg, USER_PRIORITY);
			break;

		case OPT_USERMAP:
			if (usermap) {
				if (usermap_via_chown) {
					snprintf(err_buf, sizeof err_buf,
					    "--usermap conflicts with prior --chown.\n");
					return 0;
				}
				snprintf(err_buf, sizeof err_buf,
				    "You can only specify --usermap once.\n");
				return 0;
			}
			usermap = (char *)poptGetOptArg(pc);
			usermap_via_chown = False;
			break;

		case OPT_GROUPMAP:
			if (groupmap) {
				if (groupmap_via_chown) {
					snprintf(err_buf, sizeof err_buf,
					    "--groupmap conflicts with prior --chown.\n");
					return 0;
				}
				snprintf(err_buf, sizeof err_buf,
				    "You can only specify --groupmap once.\n");
				return 0;
			}
			groupmap = (char *)poptGetOptArg(pc);
			groupmap_via_chown = False;
			break;

		case OPT_CHOWN: {
			const char *chown = poptGetOptArg(pc);
			int len;
			if ((arg = strchr(chown, ':')) != NULL)
				len = arg++ - chown;
			else
				len = strlen(chown);
			if (len) {
				if (usermap) {
					if (!usermap_via_chown) {
						snprintf(err_buf, sizeof err_buf,
						    "--chown conflicts with prior --usermap.\n");
						return 0;
					}
					snprintf(err_buf, sizeof err_buf,
					    "You can only specify a user-affecting --chown once.\n");
					return 0;
				}
				if (asprintf(&usermap, "*:%.*s", len, chown) < 0)
					out_of_memory("parse_arguments");
				usermap_via_chown = True;
			}
			if (arg && *arg) {
				if (groupmap) {
					if (!groupmap_via_chown) {
						snprintf(err_buf, sizeof err_buf,
						    "--chown conflicts with prior --groupmap.\n");
						return 0;
					}
					snprintf(err_buf, sizeof err_buf,
					    "You can only specify a group-affecting --chown once.\n");
					return 0;
				}
				if (asprintf(&groupmap, "*:%s", arg) < 0)
					out_of_memory("parse_arguments");
				groupmap_via_chown = True;
			}
			break;
		}

		case OPT_HELP:
			usage(FINFO);
			exit_cleanup(0);

		case 'A':
#ifdef SUPPORT_ACLS
			preserve_acls = 1;
			preserve_perms = 1;
			break;
#else
			/* FIXME: this should probably be ignored with a
			 * warning and then countermeasures taken to
			 * restrict group and other access in the presence
			 * of any more restrictive ACLs, but this is safe
			 * for now */
			snprintf(err_buf,sizeof(err_buf),
                                 "ACLs are not supported on this %s\n",
				 am_server ? "server" : "client");
			return 0;
#endif

		case 'X':
#ifdef SUPPORT_XATTRS
			preserve_xattrs++;
			break;
#else
			snprintf(err_buf,sizeof(err_buf),
				 "extended attributes are not supported on this %s\n",
				 am_server ? "server" : "client");
			return 0;
#endif

		default:
			/* A large opt value means that set_refuse_options()
			 * turned this option off. */
			if (opt >= OPT_REFUSED_BASE) {
				create_refuse_error(opt);
				return 0;
			}
			snprintf(err_buf, sizeof err_buf, "%s%s: %s\n",
				 am_server ? "on remote machine: " : "",
				 poptBadOption(pc, POPT_BADOPTION_NOALIAS),
				 poptStrerror(opt));
			return 0;
		}
	}

	if (protect_args < 0) {
		if (am_server)
			protect_args = 0;
		else if ((arg = getenv("RSYNC_PROTECT_ARGS")) != NULL && *arg)
			protect_args = atoi(arg) ? 1 : 0;
		else {
#ifdef RSYNC_USE_PROTECTED_ARGS
			protect_args = 1;
#else
			protect_args = 0;
#endif
		}
	}

	if (checksum_choice && strcmp(checksum_choice, "auto") != 0 && strcmp(checksum_choice, "auto,auto") != 0) {
		/* Call this early to verify the args and figure out if we need to force
		 * --whole-file. Note that the parse function will get called again later,
		 * just in case an "auto" choice needs to know the protocol_version. */
		if (parse_checksum_choice())
			whole_file = 1;
	} else
		checksum_choice = NULL;

	if (human_readable > 1 && argc == 2 && !am_server) {
		/* Allow the old meaning of 'h' (--help) on its own. */
		usage(FINFO);
		exit_cleanup(0);
	}

	if (do_compression || def_compress_level != NOT_SPECIFIED) {
		if (def_compress_level == NOT_SPECIFIED)
			def_compress_level = Z_DEFAULT_COMPRESSION;
		else if (def_compress_level < Z_DEFAULT_COMPRESSION || def_compress_level > Z_BEST_COMPRESSION) {
			snprintf(err_buf, sizeof err_buf, "--compress-level value is invalid: %d\n",
				 def_compress_level);
			return 0;
		} else if (def_compress_level == Z_NO_COMPRESSION)
			do_compression = 0;
		else if (!do_compression)
			do_compression = 1;
		if (do_compression && refused_compress) {
			create_refuse_error(refused_compress);
			return 0;
		}
#ifdef EXTERNAL_ZLIB
		if (do_compression == 1) {
			snprintf(err_buf, sizeof err_buf,
				"This rsync lacks old-style --compress due to its external zlib.  Try -zz.\n");
			if (am_server)
				return 0;
			fprintf(stderr, "%s" "Continuing without compression.\n\n", err_buf);
			do_compression = 0;
		}
#endif
	}

#ifdef HAVE_SETVBUF
	if (outbuf_mode && !am_server) {
		int mode = *(uchar *)outbuf_mode;
		if (islower(mode))
			mode = toupper(mode);
		fflush(stdout); /* Just in case... */
		switch (mode) {
		case 'N': /* None */
		case 'U': /* Unbuffered */
			mode = _IONBF;
			break;
		case 'L': /* Line */
			mode = _IOLBF;
			break;
		case 'B': /* Block */
		case 'F': /* Full */
			mode = _IOFBF;
			break;
		default:
			snprintf(err_buf, sizeof err_buf,
				"Invalid --outbuf setting -- specify N, L, or B.\n");
			return 0;
		}
		setvbuf(stdout, (char *)NULL, mode, 0);
	}

	if (msgs2stderr) {
		/* Make stderr line buffered for better sharing of the stream. */
		fflush(stderr); /* Just in case... */
		setvbuf(stderr, (char *)NULL, _IOLBF, 0);
	}
#endif

	set_output_verbosity(verbose, DEFAULT_PRIORITY);

	if (do_stats) {
		parse_output_words(info_words, info_levels,
			verbose > 1 ? "stats3" : "stats2", DEFAULT_PRIORITY);
	}

#ifdef ICONV_OPTION
	if (iconv_opt && protect_args != 2) {
		if (!am_server && strcmp(iconv_opt, "-") == 0)
			iconv_opt = NULL;
		else
			need_unsorted_flist = 1;
	}
	if (refused_no_iconv && !iconv_opt) {
		create_refuse_error(refused_no_iconv);
		return 0;
	}
#endif

	if (fuzzy_basis > 1)
		fuzzy_basis = basis_dir_cnt + 1;

	/* Don't let the client reset protect_args if it was already processed */
	if (orig_protect_args == 2 && am_server)
		protect_args = orig_protect_args;

	if (protect_args == 1 && am_server)
		return 1;

	*argv_p = argv = poptGetArgs(pc);
	*argc_p = argc = count_args(argv);

#ifndef SUPPORT_LINKS
	if (preserve_links && !am_sender) {
		snprintf(err_buf, sizeof err_buf,
			 "symlinks are not supported on this %s\n",
			 am_server ? "server" : "client");
		return 0;
	}
#endif

#ifndef SUPPORT_HARD_LINKS
	if (preserve_hard_links) {
		snprintf(err_buf, sizeof err_buf,
			 "hard links are not supported on this %s\n",
			 am_server ? "server" : "client");
		return 0;
	}
#endif

#ifdef SUPPORT_XATTRS
	if (am_root < 0 && preserve_xattrs > 1) {
		snprintf(err_buf, sizeof err_buf,
			 "--fake-super conflicts with -XX\n");
		return 0;
	}
#else
	if (am_root < 0) {
		snprintf(err_buf, sizeof err_buf,
			 "--fake-super requires an rsync with extended attributes enabled\n");
		return 0;
	}
#endif

	if (block_size > MAX_BLOCK_SIZE) {
		snprintf(err_buf, sizeof err_buf,
			 "--block-size=%lu is too large (max: %u)\n", block_size, MAX_BLOCK_SIZE);
		return 0;
	}

	if (write_batch && read_batch) {
		snprintf(err_buf, sizeof err_buf,
			"--write-batch and --read-batch can not be used together\n");
		return 0;
	}
	if (write_batch > 0 || read_batch) {
		if (am_server) {
			rprintf(FINFO,
				"ignoring --%s-batch option sent to server\n",
				write_batch ? "write" : "read");
			/* We don't actually exit_cleanup(), so that we can
			 * still service older version clients that still send
			 * batch args to server. */
			read_batch = write_batch = 0;
			batch_name = NULL;
		} else if (dry_run)
			write_batch = 0;
	} else if (write_batch < 0 && dry_run)
		write_batch = 0;
	if (read_batch && files_from) {
		snprintf(err_buf, sizeof err_buf,
			"--read-batch cannot be used with --files-from\n");
		return 0;
	}
	if (read_batch && remove_source_files) {
		snprintf(err_buf, sizeof err_buf,
			"--read-batch cannot be used with --remove-%s-files\n",
			remove_source_files == 1 ? "source" : "sent");
		return 0;
	}
	if (batch_name && strlen(batch_name) > MAX_BATCH_NAME_LEN) {
		snprintf(err_buf, sizeof err_buf,
			"the batch-file name must be %d characters or less.\n",
			MAX_BATCH_NAME_LEN);
		return 0;
	}

	if (tmpdir && strlen(tmpdir) >= MAXPATHLEN - 10) {
		snprintf(err_buf, sizeof err_buf,
			 "the --temp-dir path is WAY too long.\n");
		return 0;
	}

	if (max_delete < 0 && max_delete != INT_MIN) {
		/* Negative numbers are treated as "no deletions". */
		max_delete = 0;
	}

	if (compare_dest + copy_dest + link_dest > 1) {
		snprintf(err_buf, sizeof err_buf,
			"You may not mix --compare-dest, --copy-dest, and --link-dest.\n");
		return 0;
	}

	if (files_from) {
		if (recurse == 1) /* preserve recurse == 2 */
			recurse = 0;
		if (xfer_dirs < 0)
			xfer_dirs = 1;
	}

	if (argc < 2 && !read_batch && !am_server)
		list_only |= 1;

	if (xfer_dirs >= 4) {
		parse_filter_str(&filter_list, "- /*/*", rule_template(0), 0);
		recurse = xfer_dirs = 1;
	} else if (recurse)
		xfer_dirs = 1;
	else if (xfer_dirs < 0)
		xfer_dirs = list_only ? 1 : 0;

	if (relative_paths < 0)
		relative_paths = files_from? 1 : 0;
	if (!relative_paths)
		implied_dirs = 0;

	if (delete_before + !!delete_during + delete_after > 1) {
		snprintf(err_buf, sizeof err_buf,
			"You may not combine multiple --delete-WHEN options.\n");
		return 0;
	}
	if (delete_before || delete_during || delete_after)
		delete_mode = 1;
	else if (delete_mode || delete_excluded) {
		/* Only choose now between before & during if one is refused. */
		if (refused_delete_before) {
			if (!refused_delete_during)
				delete_during = 1;
			else {
				create_refuse_error(refused_delete_before);
				return 0;
			}
		} else if (refused_delete_during)
			delete_before = 1;
		delete_mode = 1;
	}
	if (!xfer_dirs && delete_mode) {
		snprintf(err_buf, sizeof err_buf,
			"--delete does not work without --recursive (-r) or --dirs (-d).\n");
		return 0;
	}

	if (missing_args == 3) /* simplify if both options were specified */
		missing_args = 2;
	if (refused_delete && (delete_mode || missing_args == 2)) {
		create_refuse_error(refused_delete);
		return 0;
	}

	if (remove_source_files) {
		/* We only want to infer this refusal of --remove-source-files
		 * via the refusal of "delete", not any of the "delete-FOO"
		 * options. */
		if (refused_delete && am_sender) {
			create_refuse_error(refused_delete);
			return 0;
		}
		need_messages_from_generator = 1;
	}

	if (munge_symlinks && !am_daemon) {
		STRUCT_STAT st;
		char prefix[SYMLINK_PREFIX_LEN]; /* NOT +1 ! */
		strlcpy(prefix, SYMLINK_PREFIX, sizeof prefix); /* trim the trailing slash */
		if (do_stat(prefix, &st) == 0 && S_ISDIR(st.st_mode)) {
			rprintf(FERROR, "Symlink munging is unsafe when a %s directory exists.\n",
				prefix);
			exit_cleanup(RERR_UNSUPPORTED);
		}
	}

	if (sanitize_paths) {
		int i;
		for (i = argc; i-- > 0; )
			argv[i] = sanitize_path(NULL, argv[i], "", 0, SP_KEEP_DOT_DIRS);
		if (tmpdir)
			tmpdir = sanitize_path(NULL, tmpdir, NULL, 0, SP_DEFAULT);
		if (backup_dir)
			backup_dir = sanitize_path(NULL, backup_dir, NULL, 0, SP_DEFAULT);
	}
	if (daemon_filter_list.head && !am_sender) {
		filter_rule_list *elp = &daemon_filter_list;
		if (tmpdir) {
			char *dir;
			if (!*tmpdir)
				goto options_rejected;
			dir = tmpdir + (*tmpdir == '/' ? module_dirlen : 0);
			clean_fname(dir, CFN_COLLAPSE_DOT_DOT_DIRS);
			if (check_filter(elp, FLOG, dir, 1) < 0)
				goto options_rejected;
		}
		if (backup_dir) {
			char *dir;
			if (!*backup_dir)
				goto options_rejected;
			dir = backup_dir + (*backup_dir == '/' ? module_dirlen : 0);
			clean_fname(dir, CFN_COLLAPSE_DOT_DOT_DIRS);
			if (check_filter(elp, FLOG, dir, 1) < 0)
				goto options_rejected;
		}
	}

	if (!backup_suffix)
		backup_suffix = backup_dir ? "" : BACKUP_SUFFIX;
	backup_suffix_len = strlen(backup_suffix);
	if (strchr(backup_suffix, '/') != NULL) {
		snprintf(err_buf, sizeof err_buf,
			"--suffix cannot contain slashes: %s\n",
			backup_suffix);
		return 0;
	}
	if (backup_dir) {
		size_t len;
		while (*backup_dir == '.' && backup_dir[1] == '/')
			backup_dir += 2;
		if (*backup_dir == '.' && backup_dir[1] == '\0')
			backup_dir++;
		len = strlcpy(backup_dir_buf, backup_dir, sizeof backup_dir_buf);
		if (len > sizeof backup_dir_buf - 128) {
			snprintf(err_buf, sizeof err_buf,
				"the --backup-dir path is WAY too long.\n");
			return 0;
		}
		backup_dir_len = (int)len;
		if (!backup_dir_len) {
			backup_dir_len = -1;
			backup_dir = NULL;
		} else if (backup_dir_buf[backup_dir_len - 1] != '/') {
			backup_dir_buf[backup_dir_len++] = '/';
			backup_dir_buf[backup_dir_len] = '\0';
		}
		backup_dir_remainder = sizeof backup_dir_buf - backup_dir_len;
	}
	if (backup_dir) {
		/* No need for a suffix or a protect rule. */
	} else if (!backup_suffix_len && (!am_server || !am_sender)) {
		snprintf(err_buf, sizeof err_buf,
			"--suffix cannot be empty %s\n", backup_dir_len < 0
			? "when --backup-dir is the same as the dest dir"
			: "without a --backup-dir");
		return 0;
	} else if (make_backups && delete_mode && !delete_excluded && !am_server) {
		snprintf(backup_dir_buf, sizeof backup_dir_buf,
			"P *%s", backup_suffix);
		parse_filter_str(&filter_list, backup_dir_buf, rule_template(0), 0);
	}

	if (preserve_times) {
		preserve_times = PRESERVE_FILE_TIMES;
		if (!omit_dir_times)
			preserve_times |= PRESERVE_DIR_TIMES;
#ifdef CAN_SET_SYMLINK_TIMES
		if (!omit_link_times)
			preserve_times |= PRESERVE_LINK_TIMES;
#endif
	}

	if (make_backups && !backup_dir) {
		omit_dir_times = 0; /* Implied, so avoid -O to sender. */
		preserve_times &= ~PRESERVE_DIR_TIMES;
	}

	if (stdout_format) {
		if (am_server && log_format_has(stdout_format, 'I'))
			stdout_format_has_i = 2;
		else if (log_format_has(stdout_format, 'i'))
			stdout_format_has_i = itemize_changes | 1;
		if (!log_format_has(stdout_format, 'b')
		 && !log_format_has(stdout_format, 'c')
		 && !log_format_has(stdout_format, 'C'))
			log_before_transfer = !am_server;
	} else if (itemize_changes) {
		stdout_format = "%i %n%L";
		stdout_format_has_i = itemize_changes;
		log_before_transfer = !am_server;
	}

	if (do_progress && !am_server) {
		if (!log_before_transfer && INFO_EQ(NAME, 0))
			parse_output_words(info_words, info_levels, "name", DEFAULT_PRIORITY);
		parse_output_words(info_words, info_levels, "flist2,progress", DEFAULT_PRIORITY);
	}

	if (dry_run)
		do_xfers = 0;

	set_io_timeout(io_timeout);

	if (INFO_GTE(NAME, 1) && !stdout_format) {
		stdout_format = "%n%L";
		log_before_transfer = !am_server;
	}
	if (stdout_format_has_i || log_format_has(stdout_format, 'o'))
		stdout_format_has_o_or_i = 1;

	if (logfile_name && !am_daemon) {
		if (!logfile_format) {
			logfile_format = "%i %n%L";
			logfile_format_has_i = logfile_format_has_o_or_i = 1;
		} else {
			if (log_format_has(logfile_format, 'i'))
				logfile_format_has_i = 1;
			if (logfile_format_has_i || log_format_has(logfile_format, 'o'))
				logfile_format_has_o_or_i = 1;
		}
		log_init(0);
	} else if (!am_daemon)
		logfile_format = NULL;

	if (daemon_bwlimit && (!bwlimit || bwlimit > daemon_bwlimit))
		bwlimit = daemon_bwlimit;
	if (bwlimit) {
		bwlimit_writemax = (size_t)bwlimit * 128;
		if (bwlimit_writemax < 512)
			bwlimit_writemax = 512;
	}

	if (append_mode) {
		if (whole_file > 0) {
			snprintf(err_buf, sizeof err_buf,
				 "--append cannot be used with --whole-file\n");
			return 0;
		}
		if (refused_inplace) {
			create_refuse_error(refused_inplace);
			return 0;
		}
		inplace = 1;
	}

	if (delay_updates && !partial_dir)
		partial_dir = tmp_partialdir;

	if (inplace) {
#ifdef HAVE_FTRUNCATE
		if (partial_dir) {
			snprintf(err_buf, sizeof err_buf,
				 "--%s cannot be used with --%s\n",
				 append_mode ? "append" : "inplace",
				 delay_updates ? "delay-updates" : "partial-dir");
			return 0;
		}
		/* --inplace implies --partial for refusal purposes, but we
		 * clear the keep_partial flag for internal logic purposes. */
		if (refused_partial) {
			create_refuse_error(refused_partial);
			return 0;
		}
		keep_partial = 0;
#else
		snprintf(err_buf, sizeof err_buf,
			 "--%s is not supported on this %s\n",
			 append_mode ? "append" : "inplace",
			 am_server ? "server" : "client");
		return 0;
#endif
	} else {
		if (keep_partial && !partial_dir && !am_server) {
			if ((arg = getenv("RSYNC_PARTIAL_DIR")) != NULL && *arg)
				partial_dir = strdup(arg);
		}
		if (partial_dir) {
			if (*partial_dir)
				clean_fname(partial_dir, CFN_COLLAPSE_DOT_DOT_DIRS);
			if (!*partial_dir || strcmp(partial_dir, ".") == 0)
				partial_dir = NULL;
			if (!partial_dir && refused_partial) {
				create_refuse_error(refused_partial);
				return 0;
			}
			keep_partial = 1;
		}
	}

	if (files_from) {
		char *h, *p;
		int q;
		if (argc > 2 || (!am_daemon && !am_server && argc == 1)) {
			usage(FERROR);
			exit_cleanup(RERR_SYNTAX);
		}
		if (strcmp(files_from, "-") == 0) {
			filesfrom_fd = 0;
			if (am_server)
				filesfrom_host = ""; /* reading from socket */
		} else if ((p = check_for_hostspec(files_from, &h, &q)) != 0) {
			if (am_server) {
				snprintf(err_buf, sizeof err_buf,
					"The --files-from sent to the server cannot specify a host.\n");
				return 0;
			}
			files_from = p;
			filesfrom_host = h;
			if (strcmp(files_from, "-") == 0) {
				snprintf(err_buf, sizeof err_buf,
					"Invalid --files-from remote filename\n");
				return 0;
			}
		} else {
			if (sanitize_paths)
				files_from = sanitize_path(NULL, files_from, NULL, 0, SP_DEFAULT);
			if (daemon_filter_list.head) {
				char *dir;
				if (!*files_from)
					goto options_rejected;
				dir = files_from + (*files_from == '/' ? module_dirlen : 0);
				clean_fname(dir, CFN_COLLAPSE_DOT_DOT_DIRS);
				if (check_filter(&daemon_filter_list, FLOG, dir, 0) < 0)
					goto options_rejected;
			}
			filesfrom_fd = open(files_from, O_RDONLY|O_BINARY);
			if (filesfrom_fd < 0) {
				snprintf(err_buf, sizeof err_buf,
					"failed to open files-from file %s: %s\n",
					files_from, strerror(errno));
				return 0;
			}
		}
	}

	am_starting_up = 0;

	return 1;

  options_rejected:
	snprintf(err_buf, sizeof err_buf,
		"Your options have been rejected by the server.\n");
	return 0;
}

The parse_arguments function in options.c in rsyncd in rsync before 3.1.3 does not prevent multiple --protect-args uses, which allows remote attackers to bypass an argument-sanitization protection mechanism.


tipc: better validate user input in tipc_nl_retrieve_key()

Before calling tipc_aead_key_size(ptr), we need to ensure
we have enough data to dereference ptr->keylen.

We probably also want to make sure tipc_aead_key_size()
wont overflow with malicious ptr->keylen values.

Syzbot reported:

BUG: KMSAN: uninit-value in __tipc_nl_node_set_key net/tipc/node.c:2971 [inline]
BUG: KMSAN: uninit-value in tipc_nl_node_set_key+0x9bf/0x13b0 net/tipc/node.c:3023
CPU: 0 PID: 21060 Comm: syz-executor.5 Not tainted 5.11.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:120
 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:197
 __tipc_nl_node_set_key net/tipc/node.c:2971 [inline]
 tipc_nl_node_set_key+0x9bf/0x13b0 net/tipc/node.c:3023
 genl_family_rcv_msg_doit net/netlink/genetlink.c:739 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:783 [inline]
 genl_rcv_msg+0x1319/0x1610 net/netlink/genetlink.c:800
 netlink_rcv_skb+0x6fa/0x810 net/netlink/af_netlink.c:2494
 genl_rcv+0x63/0x80 net/netlink/genetlink.c:811
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x11d6/0x14a0 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x1740/0x1840 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 ____sys_sendmsg+0xcfc/0x12f0 net/socket.c:2345
 ___sys_sendmsg net/socket.c:2399 [inline]
 __sys_sendmsg+0x714/0x830 net/socket.c:2432
 __compat_sys_sendmsg net/compat.c:347 [inline]
 __do_compat_sys_sendmsg net/compat.c:354 [inline]
 __se_compat_sys_sendmsg+0xa7/0xc0 net/compat.c:351
 __ia32_compat_sys_sendmsg+0x4a/0x70 net/compat.c:351
 do_syscall_32_irqs_on arch/x86/entry/common.c:79 [inline]
 __do_fast_syscall_32+0x102/0x160 arch/x86/entry/common.c:141
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:166
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:209
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f60549
Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f555a5fc EFLAGS: 00000296 ORIG_RAX: 0000000000000172
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000200
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:104
 kmsan_slab_alloc+0x8d/0xe0 mm/kmsan/kmsan_hooks.c:76
 slab_alloc_node mm/slub.c:2907 [inline]
 __kmalloc_node_track_caller+0xa37/0x1430 mm/slub.c:4527
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x2f8/0xb30 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1099 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1176 [inline]
 netlink_sendmsg+0xdbc/0x1840 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 ____sys_sendmsg+0xcfc/0x12f0 net/socket.c:2345
 ___sys_sendmsg net/socket.c:2399 [inline]
 __sys_sendmsg+0x714/0x830 net/socket.c:2432
 __compat_sys_sendmsg net/compat.c:347 [inline]
 __do_compat_sys_sendmsg net/compat.c:354 [inline]
 __se_compat_sys_sendmsg+0xa7/0xc0 net/compat.c:351
 __ia32_compat_sys_sendmsg+0x4a/0x70 net/compat.c:351
 do_syscall_32_irqs_on arch/x86/entry/common.c:79 [inline]
 __do_fast_syscall_32+0x102/0x160 arch/x86/entry/common.c:141
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:166
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:209
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Fixes: e1f32190cf7d ("tipc: add support for AEAD key setting via netlink")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tuong Lien <tuong.t.lien@dektech.com.au>
Cc: Jon Maloy <jmaloy@redhat.com>
Cc: Ying Xue <ying.xue@windriver.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

void tipc_node_get(struct tipc_node *node)
{
	kref_get(&node->kref);
}

An issue was discovered in the Linux kernel before 5.11.11. tipc_nl_retrieve_key in net/tipc/node.c does not properly validate certain data sizes, aka CID-0217ed2848e8.


static struct tipc_node *tipc_node_find_by_name(struct net *net,
						const char *link_name,
						unsigned int *bearer_id)
{
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	struct tipc_link *l;
	struct tipc_node *n;
	struct tipc_node *found_node = NULL;
	int i;

	*bearer_id = 0;
	rcu_read_lock();
	list_for_each_entry_rcu(n, &tn->node_list, list) {
		tipc_node_read_lock(n);
		for (i = 0; i < MAX_BEARERS; i++) {
			l = n->links[i].link;
			if (l && !strcmp(tipc_link_name(l), link_name)) {
				*bearer_id = i;
				found_node = n;
				break;
			}
		}
		tipc_node_read_unlock(n);
		if (found_node)
			break;
	}
	rcu_read_unlock();

	return found_node;
}


int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
{
	int err;
	int res = 0;
	int bearer_id;
	char *name;
	struct tipc_link *link;
	struct tipc_node *node;
	struct sk_buff_head xmitq;
	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
	struct net *net = sock_net(skb->sk);

	__skb_queue_head_init(&xmitq);

	if (!info->attrs[TIPC_NLA_LINK])
		return -EINVAL;

	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
					  info->attrs[TIPC_NLA_LINK],
					  tipc_nl_link_policy, info->extack);
	if (err)
		return err;

	if (!attrs[TIPC_NLA_LINK_NAME])
		return -EINVAL;

	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);

	if (strcmp(name, tipc_bclink_name) == 0)
		return tipc_nl_bc_link_set(net, attrs);

	node = tipc_node_find_by_name(net, name, &bearer_id);
	if (!node)
		return -EINVAL;

	tipc_node_read_lock(node);

	link = node->links[bearer_id].link;
	if (!link) {
		res = -EINVAL;
		goto out;
	}

	if (attrs[TIPC_NLA_LINK_PROP]) {
		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];

		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props);
		if (err) {
			res = err;
			goto out;
		}

		if (props[TIPC_NLA_PROP_TOL]) {
			u32 tol;

			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
			tipc_link_set_tolerance(link, tol, &xmitq);
		}
		if (props[TIPC_NLA_PROP_PRIO]) {
			u32 prio;

			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
			tipc_link_set_prio(link, prio, &xmitq);
		}
		if (props[TIPC_NLA_PROP_WIN]) {
			u32 max_win;

			max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
			tipc_link_set_queue_limits(link,
						   tipc_link_min_win(link),
						   max_win);
		}
	}

out:
	tipc_node_read_unlock(node);
	tipc_bearer_xmit(net, bearer_id, &xmitq, &node->links[bearer_id].maddr,
			 NULL);
	return res;
}


void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
{
	struct sk_buff_head xmitq;
	struct tipc_link_entry *le;
	struct tipc_msg *hdr;
	struct tipc_node *n;
	int bearer_id = b->identity;
	u32 self = tipc_own_addr(net);
	int usr, rc = 0;
	u16 bc_ack;
#ifdef CONFIG_TIPC_CRYPTO
	struct tipc_ehdr *ehdr;

	/* Check if message must be decrypted first */
	if (TIPC_SKB_CB(skb)->decrypted || !tipc_ehdr_validate(skb))
		goto rcv;

	ehdr = (struct tipc_ehdr *)skb->data;
	if (likely(ehdr->user != LINK_CONFIG)) {
		n = tipc_node_find(net, ntohl(ehdr->addr));
		if (unlikely(!n))
			goto discard;
	} else {
		n = tipc_node_find_by_id(net, ehdr->id);
	}
	tipc_crypto_rcv(net, (n) ? n->crypto_rx : NULL, &skb, b);
	if (!skb)
		return;

rcv:
#endif
	/* Ensure message is well-formed before touching the header */
	if (unlikely(!tipc_msg_validate(&skb)))
		goto discard;
	__skb_queue_head_init(&xmitq);
	hdr = buf_msg(skb);
	usr = msg_user(hdr);
	bc_ack = msg_bcast_ack(hdr);

	/* Handle arrival of discovery or broadcast packet */
	if (unlikely(msg_non_seq(hdr))) {
		if (unlikely(usr == LINK_CONFIG))
			return tipc_disc_rcv(net, skb, b);
		else
			return tipc_node_bc_rcv(net, skb, bearer_id);
	}

	/* Discard unicast link messages destined for another node */
	if (unlikely(!msg_short(hdr) && (msg_destnode(hdr) != self)))
		goto discard;

	/* Locate neighboring node that sent packet */
	n = tipc_node_find(net, msg_prevnode(hdr));
	if (unlikely(!n))
		goto discard;
	le = &n->links[bearer_id];

	/* Ensure broadcast reception is in synch with peer's send state */
	if (unlikely(usr == LINK_PROTOCOL)) {
		if (unlikely(skb_linearize(skb))) {
			tipc_node_put(n);
			goto discard;
		}
		hdr = buf_msg(skb);
		tipc_node_bc_sync_rcv(n, hdr, bearer_id, &xmitq);
	} else if (unlikely(tipc_link_acked(n->bc_entry.link) != bc_ack)) {
		tipc_bcast_ack_rcv(net, n->bc_entry.link, hdr);
	}

	/* Receive packet directly if conditions permit */
	tipc_node_read_lock(n);
	if (likely((n->state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) {
		spin_lock_bh(&le->lock);
		if (le->link) {
			rc = tipc_link_rcv(le->link, skb, &xmitq);
			skb = NULL;
		}
		spin_unlock_bh(&le->lock);
	}
	tipc_node_read_unlock(n);

	/* Check/update node state before receiving */
	if (unlikely(skb)) {
		if (unlikely(skb_linearize(skb)))
			goto out_node_put;
		tipc_node_write_lock(n);
		if (tipc_node_check_state(n, skb, bearer_id, &xmitq)) {
			if (le->link) {
				rc = tipc_link_rcv(le->link, skb, &xmitq);
				skb = NULL;
			}
		}
		tipc_node_write_unlock(n);
	}

	if (unlikely(rc & TIPC_LINK_UP_EVT))
		tipc_node_link_up(n, bearer_id, &xmitq);

	if (unlikely(rc & TIPC_LINK_DOWN_EVT))
		tipc_node_link_down(n, bearer_id, false);

	if (unlikely(!skb_queue_empty(&n->bc_entry.namedq)))
		tipc_named_rcv(net, &n->bc_entry.namedq,
			       &n->bc_entry.named_rcv_nxt,
			       &n->bc_entry.named_open);

	if (unlikely(!skb_queue_empty(&n->bc_entry.inputq1)))
		tipc_node_mcast_rcv(n);

	if (!skb_queue_empty(&le->inputq))
		tipc_sk_rcv(net, &le->inputq);

	if (!skb_queue_empty(&xmitq))
		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);

out_node_put:
	tipc_node_put(n);
discard:
	kfree_skb(skb);
}


int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
{
	struct net *net = genl_info_net(info);
	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
	struct tipc_nl_msg msg;
	char *name;
	int err;

	msg.portid = info->snd_portid;
	msg.seq = info->snd_seq;

	if (!info->attrs[TIPC_NLA_LINK])
		return -EINVAL;

	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
					  info->attrs[TIPC_NLA_LINK],
					  tipc_nl_link_policy, info->extack);
	if (err)
		return err;

	if (!attrs[TIPC_NLA_LINK_NAME])
		return -EINVAL;

	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);

	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
	if (!msg.skb)
		return -ENOMEM;

	if (strcmp(name, tipc_bclink_name) == 0) {
		err = tipc_nl_add_bc_link(net, &msg, tipc_net(net)->bcl);
		if (err)
			goto err_free;
	} else {
		int bearer_id;
		struct tipc_node *node;
		struct tipc_link *link;

		node = tipc_node_find_by_name(net, name, &bearer_id);
		if (!node) {
			err = -EINVAL;
			goto err_free;
		}

		tipc_node_read_lock(node);
		link = node->links[bearer_id].link;
		if (!link) {
			tipc_node_read_unlock(node);
			err = -EINVAL;
			goto err_free;
		}

		err = __tipc_nl_add_link(net, &msg, link, 0);
		tipc_node_read_unlock(node);
		if (err)
			goto err_free;
	}

	return genlmsg_reply(msg.skb, info);

err_free:
	nlmsg_free(msg.skb);
	return err;
}


void tipc_node_pre_cleanup_net(struct net *exit_net)
{
	struct tipc_node *n;
	struct tipc_net *tn;
	struct net *tmp;

	rcu_read_lock();
	for_each_net_rcu(tmp) {
		if (tmp == exit_net)
			continue;
		tn = tipc_net(tmp);
		if (!tn)
			continue;
		spin_lock_bh(&tn->node_list_lock);
		list_for_each_entry_rcu(n, &tn->node_list, list) {
			if (!n->peer_net)
				continue;
			if (n->peer_net != exit_net)
				continue;
			tipc_node_write_lock(n);
			n->peer_net = NULL;
			n->peer_hash_mix = 0;
			tipc_node_write_unlock_fast(n);
			break;
		}
		spin_unlock_bh(&tn->node_list_lock);
	}
	rcu_read_unlock();
}


static void tipc_node_free(struct rcu_head *rp)
{
	struct tipc_node *n = container_of(rp, struct tipc_node, rcu);

#ifdef CONFIG_TIPC_CRYPTO
	tipc_crypto_stop(&n->crypto_rx);
#endif
	kfree(n);
}


bool tipc_node_get_id(struct net *net, u32 addr, u8 *id)
{
	u8 *own_id = tipc_own_id(net);
	struct tipc_node *n;

	if (!own_id)
		return true;

	if (addr == tipc_own_addr(net)) {
		memcpy(id, own_id, TIPC_NODEID_LEN);
		return true;
	}
	n = tipc_node_find(net, addr);
	if (!n)
		return false;

	memcpy(id, &n->peer_id, TIPC_NODEID_LEN);
	tipc_node_put(n);
	return true;
}


int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info)
{
	struct net *net = sock_net(skb->sk);
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
	struct tipc_node *peer, *temp_node;
	u8 node_id[NODE_ID_LEN];
	u64 *w0 = (u64 *)&node_id[0];
	u64 *w1 = (u64 *)&node_id[8];
	u32 addr;
	int err;

	/* We identify the peer by its net */
	if (!info->attrs[TIPC_NLA_NET])
		return -EINVAL;

	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_NET_MAX,
					  info->attrs[TIPC_NLA_NET],
					  tipc_nl_net_policy, info->extack);
	if (err)
		return err;

	/* attrs[TIPC_NLA_NET_NODEID] and attrs[TIPC_NLA_NET_ADDR] are
	 * mutually exclusive cases
	 */
	if (attrs[TIPC_NLA_NET_ADDR]) {
		addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
		if (!addr)
			return -EINVAL;
	}

	if (attrs[TIPC_NLA_NET_NODEID]) {
		if (!attrs[TIPC_NLA_NET_NODEID_W1])
			return -EINVAL;
		*w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]);
		*w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]);
		addr = hash128to32(node_id);
	}

	if (in_own_node(net, addr))
		return -ENOTSUPP;

	spin_lock_bh(&tn->node_list_lock);
	peer = tipc_node_find(net, addr);
	if (!peer) {
		spin_unlock_bh(&tn->node_list_lock);
		return -ENXIO;
	}

	tipc_node_write_lock(peer);
	if (peer->state != SELF_DOWN_PEER_DOWN &&
	    peer->state != SELF_DOWN_PEER_LEAVING) {
		tipc_node_write_unlock(peer);
		err = -EBUSY;
		goto err_out;
	}

	tipc_node_clear_links(peer);
	tipc_node_write_unlock(peer);
	tipc_node_delete(peer);

	/* Calculate cluster capabilities */
	tn->capabilities = TIPC_NODE_CAPABILITIES;
	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
		tn->capabilities &= temp_node->capabilities;
	}
	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
	err = 0;
err_out:
	tipc_node_put(peer);
	spin_unlock_bh(&tn->node_list_lock);

	return err;
}


int tipc_nl_node_get_monitor(struct sk_buff *skb, struct genl_info *info)
{
	struct net *net = sock_net(skb->sk);
	struct tipc_nl_msg msg;
	int err;

	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
	if (!msg.skb)
		return -ENOMEM;
	msg.portid = info->snd_portid;
	msg.seq = info->snd_seq;

	err = __tipc_nl_add_monitor_prop(net, &msg);
	if (err) {
		nlmsg_free(msg.skb);
		return err;
	}

	return genlmsg_reply(msg.skb, info);
}


int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
{
	int err;
	char *link_name;
	unsigned int bearer_id;
	struct tipc_link *link;
	struct tipc_node *node;
	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
	struct net *net = sock_net(skb->sk);
	struct tipc_net *tn = tipc_net(net);
	struct tipc_link_entry *le;

	if (!info->attrs[TIPC_NLA_LINK])
		return -EINVAL;

	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
					  info->attrs[TIPC_NLA_LINK],
					  tipc_nl_link_policy, info->extack);
	if (err)
		return err;

	if (!attrs[TIPC_NLA_LINK_NAME])
		return -EINVAL;

	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);

	err = -EINVAL;
	if (!strcmp(link_name, tipc_bclink_name)) {
		err = tipc_bclink_reset_stats(net, tipc_bc_sndlink(net));
		if (err)
			return err;
		return 0;
	} else if (strstr(link_name, tipc_bclink_name)) {
		rcu_read_lock();
		list_for_each_entry_rcu(node, &tn->node_list, list) {
			tipc_node_read_lock(node);
			link = node->bc_entry.link;
			if (link && !strcmp(link_name, tipc_link_name(link))) {
				err = tipc_bclink_reset_stats(net, link);
				tipc_node_read_unlock(node);
				break;
			}
			tipc_node_read_unlock(node);
		}
		rcu_read_unlock();
		return err;
	}

	node = tipc_node_find_by_name(net, link_name, &bearer_id);
	if (!node)
		return -EINVAL;

	le = &node->links[bearer_id];
	tipc_node_read_lock(node);
	spin_lock_bh(&le->lock);
	link = node->links[bearer_id].link;
	if (!link) {
		spin_unlock_bh(&le->lock);
		tipc_node_read_unlock(node);
		return -EINVAL;
	}
	tipc_link_reset_stats(link);
	spin_unlock_bh(&le->lock);
	tipc_node_read_unlock(node);
	return 0;
}


struct tipc_crypto *tipc_node_crypto_rx_by_list(struct list_head *pos)
{
	return container_of(pos, struct tipc_node, list)->crypto_rx;
}


static void tipc_node_write_unlock_fast(struct tipc_node *n)
{
	write_unlock_bh(&n->lock);
}


int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
	int err;
	struct net *net = sock_net(skb->sk);
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	int done = cb->args[0];
	int last_addr = cb->args[1];
	struct tipc_node *node;
	struct tipc_nl_msg msg;

	if (done)
		return 0;

	msg.skb = skb;
	msg.portid = NETLINK_CB(cb->skb).portid;
	msg.seq = cb->nlh->nlmsg_seq;

	rcu_read_lock();
	if (last_addr) {
		node = tipc_node_find(net, last_addr);
		if (!node) {
			rcu_read_unlock();
			/* We never set seq or call nl_dump_check_consistent()
			 * this means that setting prev_seq here will cause the
			 * consistence check to fail in the netlink callback
			 * handler. Resulting in the NLMSG_DONE message having
			 * the NLM_F_DUMP_INTR flag set if the node state
			 * changed while we released the lock.
			 */
			cb->prev_seq = 1;
			return -EPIPE;
		}
		tipc_node_put(node);
	}

	list_for_each_entry_rcu(node, &tn->node_list, list) {
		if (node->preliminary)
			continue;
		if (last_addr) {
			if (node->addr == last_addr)
				last_addr = 0;
			else
				continue;
		}

		tipc_node_read_lock(node);
		err = __tipc_nl_add_node(&msg, node);
		if (err) {
			last_addr = node->addr;
			tipc_node_read_unlock(node);
			goto out;
		}

		tipc_node_read_unlock(node);
	}
	done = 1;
out:
	cb->args[0] = done;
	cb->args[1] = last_addr;
	rcu_read_unlock();

	return skb->len;
}


static void tipc_node_timeout(struct timer_list *t)
{
	struct tipc_node *n = from_timer(n, t, timer);
	struct tipc_link_entry *le;
	struct sk_buff_head xmitq;
	int remains = n->link_cnt;
	int bearer_id;
	int rc = 0;

	trace_tipc_node_timeout(n, false, " ");
	if (!node_is_up(n) && tipc_node_cleanup(n)) {
		/*Removing the reference of Timer*/
		tipc_node_put(n);
		return;
	}

#ifdef CONFIG_TIPC_CRYPTO
	/* Take any crypto key related actions first */
	tipc_crypto_timeout(n->crypto_rx);
#endif
	__skb_queue_head_init(&xmitq);

	/* Initial node interval to value larger (10 seconds), then it will be
	 * recalculated with link lowest tolerance
	 */
	tipc_node_read_lock(n);
	n->keepalive_intv = 10000;
	tipc_node_read_unlock(n);
	for (bearer_id = 0; remains && (bearer_id < MAX_BEARERS); bearer_id++) {
		tipc_node_read_lock(n);
		le = &n->links[bearer_id];
		if (le->link) {
			spin_lock_bh(&le->lock);
			/* Link tolerance may change asynchronously: */
			tipc_node_calculate_timer(n, le->link);
			rc = tipc_link_timeout(le->link, &xmitq);
			spin_unlock_bh(&le->lock);
			remains--;
		}
		tipc_node_read_unlock(n);
		tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr, n);
		if (rc & TIPC_LINK_DOWN_EVT)
			tipc_node_link_down(n, bearer_id, false);
	}
	mod_timer(&n->timer, jiffies + msecs_to_jiffies(n->keepalive_intv));
}


static int __tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
{
	struct nlattr *attrs[TIPC_NLA_NODE_MAX + 1];
	struct net *net = sock_net(skb->sk);
	struct tipc_crypto *tx = tipc_net(net)->crypto_tx, *c = tx;
	struct tipc_node *n = NULL;
	struct tipc_aead_key *ukey;
	bool rekeying = true, master_key = false;
	u8 *id, *own_id, mode;
	u32 intv = 0;
	int rc = 0;

	if (!info->attrs[TIPC_NLA_NODE])
		return -EINVAL;

	rc = nla_parse_nested(attrs, TIPC_NLA_NODE_MAX,
			      info->attrs[TIPC_NLA_NODE],
			      tipc_nl_node_policy, info->extack);
	if (rc)
		return rc;

	own_id = tipc_own_id(net);
	if (!own_id) {
		GENL_SET_ERR_MSG(info, "not found own node identity (set id?)");
		return -EPERM;
	}

	rc = tipc_nl_retrieve_rekeying(attrs, &intv);
	if (rc == -ENODATA)
		rekeying = false;

	rc = tipc_nl_retrieve_key(attrs, &ukey);
	if (rc == -ENODATA && rekeying)
		goto rekeying;
	else if (rc)
		return rc;

	rc = tipc_aead_key_validate(ukey, info);
	if (rc)
		return rc;

	rc = tipc_nl_retrieve_nodeid(attrs, &id);
	switch (rc) {
	case -ENODATA:
		mode = CLUSTER_KEY;
		master_key = !!(attrs[TIPC_NLA_NODE_KEY_MASTER]);
		break;
	case 0:
		mode = PER_NODE_KEY;
		if (memcmp(id, own_id, NODE_ID_LEN)) {
			n = tipc_node_find_by_id(net, id) ?:
				tipc_node_create(net, 0, id, 0xffffu, 0, true);
			if (unlikely(!n))
				return -ENOMEM;
			c = n->crypto_rx;
		}
		break;
	default:
		return rc;
	}

	/* Initiate the TX/RX key */
	rc = tipc_crypto_key_init(c, ukey, mode, master_key);
	if (n)
		tipc_node_put(n);

	if (unlikely(rc < 0)) {
		GENL_SET_ERR_MSG(info, "unable to initiate or attach new key");
		return rc;
	} else if (c == tx) {
		/* Distribute TX key but not master one */
		if (!master_key && tipc_crypto_key_distr(tx, rc, NULL))
			GENL_SET_ERR_MSG(info, "failed to replicate new key");
rekeying:
		/* Schedule TX rekeying if needed */
		tipc_crypto_rekeying_sched(tx, rekeying, intv);
	}

	return 0;
}


void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr)
{
	struct tipc_node *n;

	if (in_own_node(net, addr))
		return;

	n = tipc_node_find(net, addr);
	if (!n) {
		pr_warn("Node unsubscribe rejected, unknown node 0x%x\n", addr);
		return;
	}
	tipc_node_write_lock(n);
	list_del_init(subscr);
	tipc_node_write_unlock_fast(n);
	tipc_node_put(n);
}


static void node_lost_contact(struct tipc_node *n,
			      struct sk_buff_head *inputq)
{
	struct tipc_sock_conn *conn, *safe;
	struct tipc_link *l;
	struct list_head *conns = &n->conn_sks;
	struct sk_buff *skb;
	uint i;

	pr_debug("Lost contact with %x\n", n->addr);
	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
	trace_tipc_node_lost_contact(n, true, " ");

	/* Clean up broadcast state */
	tipc_bcast_remove_peer(n->net, n->bc_entry.link);
	skb_queue_purge(&n->bc_entry.namedq);

	/* Abort any ongoing link failover */
	for (i = 0; i < MAX_BEARERS; i++) {
		l = n->links[i].link;
		if (l)
			tipc_link_fsm_evt(l, LINK_FAILOVER_END_EVT);
	}

	/* Notify publications from this node */
	n->action_flags |= TIPC_NOTIFY_NODE_DOWN;
	n->peer_net = NULL;
	n->peer_hash_mix = 0;
	/* Notify sockets connected to node */
	list_for_each_entry_safe(conn, safe, conns, list) {
		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
				      SHORT_H_SIZE, 0, tipc_own_addr(n->net),
				      conn->peer_node, conn->port,
				      conn->peer_port, TIPC_ERR_NO_NODE);
		if (likely(skb))
			skb_queue_tail(inputq, skb);
		list_del(&conn->list);
		kfree(conn);
	}
}


static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
				  struct sk_buff_head *xmitq,
				  struct tipc_media_addr **maddr)
{
	struct tipc_link_entry *le = &n->links[*bearer_id];
	int *slot0 = &n->active_links[0];
	int *slot1 = &n->active_links[1];
	int i, highest = 0, prio;
	struct tipc_link *l, *_l, *tnl;

	l = n->links[*bearer_id].link;
	if (!l || tipc_link_is_reset(l))
		return;

	n->working_links--;
	n->action_flags |= TIPC_NOTIFY_LINK_DOWN;
	n->link_id = tipc_link_id(l);

	tipc_bearer_remove_dest(n->net, *bearer_id, n->addr);

	pr_debug("Lost link <%s> on network plane %c\n",
		 tipc_link_name(l), tipc_link_plane(l));

	/* Select new active link if any available */
	*slot0 = INVALID_BEARER_ID;
	*slot1 = INVALID_BEARER_ID;
	for (i = 0; i < MAX_BEARERS; i++) {
		_l = n->links[i].link;
		if (!_l || !tipc_link_is_up(_l))
			continue;
		if (_l == l)
			continue;
		prio = tipc_link_prio(_l);
		if (prio < highest)
			continue;
		if (prio > highest) {
			highest = prio;
			*slot0 = i;
			*slot1 = i;
			continue;
		}
		*slot1 = i;
	}

	if (!node_is_up(n)) {
		if (tipc_link_peer_is_down(l))
			tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
		tipc_node_fsm_evt(n, SELF_LOST_CONTACT_EVT);
		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down!");
		tipc_link_fsm_evt(l, LINK_RESET_EVT);
		tipc_link_reset(l);
		tipc_link_build_reset_msg(l, xmitq);
		*maddr = &n->links[*bearer_id].maddr;
		node_lost_contact(n, &le->inputq);
		tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
		return;
	}
	tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);

	/* There is still a working link => initiate failover */
	*bearer_id = n->active_links[0];
	tnl = n->links[*bearer_id].link;
	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
	tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq);
	trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down -> failover!");
	tipc_link_reset(l);
	tipc_link_fsm_evt(l, LINK_RESET_EVT);
	tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
	*maddr = &n->links[*bearer_id].maddr;
}


static void tipc_node_delete_from_list(struct tipc_node *node)
{
#ifdef CONFIG_TIPC_CRYPTO
	tipc_crypto_key_flush(node->crypto_rx);
#endif
	list_del_rcu(&node->list);
	hlist_del_rcu(&node->hash);
	tipc_node_put(node);
}


static void tipc_node_delete(struct tipc_node *node)
{
	trace_tipc_node_delete(node, true, " ");
	tipc_node_delete_from_list(node);

	del_timer_sync(&node->timer);
	tipc_node_put(node);
}


void tipc_node_put(struct tipc_node *node)
{
	kref_put(&node->kref, tipc_node_kref_release);
}


int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
		   u32 dnode, int selector)
{
	struct tipc_link_entry *le = NULL;
	struct tipc_node *n;
	struct sk_buff_head xmitq;
	bool node_up = false;
	int bearer_id;
	int rc;

	if (in_own_node(net, dnode)) {
		tipc_loopback_trace(net, list);
		spin_lock_init(&list->lock);
		tipc_sk_rcv(net, list);
		return 0;
	}

	n = tipc_node_find(net, dnode);
	if (unlikely(!n)) {
		__skb_queue_purge(list);
		return -EHOSTUNREACH;
	}

	tipc_node_read_lock(n);
	node_up = node_is_up(n);
	if (node_up && n->peer_net && check_net(n->peer_net)) {
		/* xmit inner linux container */
		tipc_lxc_xmit(n->peer_net, list);
		if (likely(skb_queue_empty(list))) {
			tipc_node_read_unlock(n);
			tipc_node_put(n);
			return 0;
		}
	}

	bearer_id = n->active_links[selector & 1];
	if (unlikely(bearer_id == INVALID_BEARER_ID)) {
		tipc_node_read_unlock(n);
		tipc_node_put(n);
		__skb_queue_purge(list);
		return -EHOSTUNREACH;
	}

	__skb_queue_head_init(&xmitq);
	le = &n->links[bearer_id];
	spin_lock_bh(&le->lock);
	rc = tipc_link_xmit(le->link, list, &xmitq);
	spin_unlock_bh(&le->lock);
	tipc_node_read_unlock(n);

	if (unlikely(rc == -ENOBUFS))
		tipc_node_link_down(n, bearer_id, false);
	else
		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);

	tipc_node_put(n);

	return rc;
}


static void tipc_node_fsm_evt(struct tipc_node *n, int evt)
{
	int state = n->state;

	switch (state) {
	case SELF_DOWN_PEER_DOWN:
		switch (evt) {
		case SELF_ESTABL_CONTACT_EVT:
			state = SELF_UP_PEER_COMING;
			break;
		case PEER_ESTABL_CONTACT_EVT:
			state = SELF_COMING_PEER_UP;
			break;
		case SELF_LOST_CONTACT_EVT:
		case PEER_LOST_CONTACT_EVT:
			break;
		case NODE_SYNCH_END_EVT:
		case NODE_SYNCH_BEGIN_EVT:
		case NODE_FAILOVER_BEGIN_EVT:
		case NODE_FAILOVER_END_EVT:
		default:
			goto illegal_evt;
		}
		break;
	case SELF_UP_PEER_UP:
		switch (evt) {
		case SELF_LOST_CONTACT_EVT:
			state = SELF_DOWN_PEER_LEAVING;
			break;
		case PEER_LOST_CONTACT_EVT:
			state = SELF_LEAVING_PEER_DOWN;
			break;
		case NODE_SYNCH_BEGIN_EVT:
			state = NODE_SYNCHING;
			break;
		case NODE_FAILOVER_BEGIN_EVT:
			state = NODE_FAILINGOVER;
			break;
		case SELF_ESTABL_CONTACT_EVT:
		case PEER_ESTABL_CONTACT_EVT:
		case NODE_SYNCH_END_EVT:
		case NODE_FAILOVER_END_EVT:
			break;
		default:
			goto illegal_evt;
		}
		break;
	case SELF_DOWN_PEER_LEAVING:
		switch (evt) {
		case PEER_LOST_CONTACT_EVT:
			state = SELF_DOWN_PEER_DOWN;
			break;
		case SELF_ESTABL_CONTACT_EVT:
		case PEER_ESTABL_CONTACT_EVT:
		case SELF_LOST_CONTACT_EVT:
			break;
		case NODE_SYNCH_END_EVT:
		case NODE_SYNCH_BEGIN_EVT:
		case NODE_FAILOVER_BEGIN_EVT:
		case NODE_FAILOVER_END_EVT:
		default:
			goto illegal_evt;
		}
		break;
	case SELF_UP_PEER_COMING:
		switch (evt) {
		case PEER_ESTABL_CONTACT_EVT:
			state = SELF_UP_PEER_UP;
			break;
		case SELF_LOST_CONTACT_EVT:
			state = SELF_DOWN_PEER_DOWN;
			break;
		case SELF_ESTABL_CONTACT_EVT:
		case PEER_LOST_CONTACT_EVT:
		case NODE_SYNCH_END_EVT:
		case NODE_FAILOVER_BEGIN_EVT:
			break;
		case NODE_SYNCH_BEGIN_EVT:
		case NODE_FAILOVER_END_EVT:
		default:
			goto illegal_evt;
		}
		break;
	case SELF_COMING_PEER_UP:
		switch (evt) {
		case SELF_ESTABL_CONTACT_EVT:
			state = SELF_UP_PEER_UP;
			break;
		case PEER_LOST_CONTACT_EVT:
			state = SELF_DOWN_PEER_DOWN;
			break;
		case SELF_LOST_CONTACT_EVT:
		case PEER_ESTABL_CONTACT_EVT:
			break;
		case NODE_SYNCH_END_EVT:
		case NODE_SYNCH_BEGIN_EVT:
		case NODE_FAILOVER_BEGIN_EVT:
		case NODE_FAILOVER_END_EVT:
		default:
			goto illegal_evt;
		}
		break;
	case SELF_LEAVING_PEER_DOWN:
		switch (evt) {
		case SELF_LOST_CONTACT_EVT:
			state = SELF_DOWN_PEER_DOWN;
			break;
		case SELF_ESTABL_CONTACT_EVT:
		case PEER_ESTABL_CONTACT_EVT:
		case PEER_LOST_CONTACT_EVT:
			break;
		case NODE_SYNCH_END_EVT:
		case NODE_SYNCH_BEGIN_EVT:
		case NODE_FAILOVER_BEGIN_EVT:
		case NODE_FAILOVER_END_EVT:
		default:
			goto illegal_evt;
		}
		break;
	case NODE_FAILINGOVER:
		switch (evt) {
		case SELF_LOST_CONTACT_EVT:
			state = SELF_DOWN_PEER_LEAVING;
			break;
		case PEER_LOST_CONTACT_EVT:
			state = SELF_LEAVING_PEER_DOWN;
			break;
		case NODE_FAILOVER_END_EVT:
			state = SELF_UP_PEER_UP;
			break;
		case NODE_FAILOVER_BEGIN_EVT:
		case SELF_ESTABL_CONTACT_EVT:
		case PEER_ESTABL_CONTACT_EVT:
			break;
		case NODE_SYNCH_BEGIN_EVT:
		case NODE_SYNCH_END_EVT:
		default:
			goto illegal_evt;
		}
		break;
	case NODE_SYNCHING:
		switch (evt) {
		case SELF_LOST_CONTACT_EVT:
			state = SELF_DOWN_PEER_LEAVING;
			break;
		case PEER_LOST_CONTACT_EVT:
			state = SELF_LEAVING_PEER_DOWN;
			break;
		case NODE_SYNCH_END_EVT:
			state = SELF_UP_PEER_UP;
			break;
		case NODE_FAILOVER_BEGIN_EVT:
			state = NODE_FAILINGOVER;
			break;
		case NODE_SYNCH_BEGIN_EVT:
		case SELF_ESTABL_CONTACT_EVT:
		case PEER_ESTABL_CONTACT_EVT:
			break;
		case NODE_FAILOVER_END_EVT:
		default:
			goto illegal_evt;
		}
		break;
	default:
		pr_err("Unknown node fsm state %x\n", state);
		break;
	}
	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
	n->state = state;
	return;

illegal_evt:
	pr_err("Illegal node fsm evt %x in state %x\n", evt, state);
	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
}


u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr)
{
	struct tipc_net *tn = tipc_net(net);
	struct tipc_node *n;
	bool preliminary;
	u32 sugg_addr;

	/* Suggest new address if some other peer is using this one */
	n = tipc_node_find(net, addr);
	if (n) {
		if (!memcmp(n->peer_id, id, NODE_ID_LEN))
			addr = 0;
		tipc_node_put(n);
		if (!addr)
			return 0;
		return tipc_node_suggest_addr(net, addr);
	}

	/* Suggest previously used address if peer is known */
	n = tipc_node_find_by_id(net, id);
	if (n) {
		sugg_addr = n->addr;
		preliminary = n->preliminary;
		tipc_node_put(n);
		if (!preliminary)
			return sugg_addr;
	}

	/* Even this node may be in conflict */
	if (tn->trial_addr == addr)
		return tipc_node_suggest_addr(net, addr);

	return 0;
}


static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
{
	void *hdr;
	struct nlattr *attrs;

	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
			  NLM_F_MULTI, TIPC_NL_NODE_GET);
	if (!hdr)
		return -EMSGSIZE;

	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NODE);
	if (!attrs)
		goto msg_full;

	if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
		goto attr_msg_full;
	if (node_is_up(node))
		if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
			goto attr_msg_full;

	nla_nest_end(msg->skb, attrs);
	genlmsg_end(msg->skb, hdr);

	return 0;

attr_msg_full:
	nla_nest_cancel(msg->skb, attrs);
msg_full:
	genlmsg_cancel(msg->skb, hdr);

	return -EMSGSIZE;
}


void tipc_node_apply_property(struct net *net, struct tipc_bearer *b,
			      int prop)
{
	struct tipc_net *tn = tipc_net(net);
	int bearer_id = b->identity;
	struct sk_buff_head xmitq;
	struct tipc_link_entry *e;
	struct tipc_node *n;

	__skb_queue_head_init(&xmitq);

	rcu_read_lock();

	list_for_each_entry_rcu(n, &tn->node_list, list) {
		tipc_node_write_lock(n);
		e = &n->links[bearer_id];
		if (e->link) {
			if (prop == TIPC_NLA_PROP_TOL)
				tipc_link_set_tolerance(e->link, b->tolerance,
							&xmitq);
			else if (prop == TIPC_NLA_PROP_MTU)
				tipc_link_set_mtu(e->link, b->mtu);

			/* Update MTU for node link entry */
			e->mtu = tipc_link_mss(e->link);
		}

		tipc_node_write_unlock(n);
		tipc_bearer_xmit(net, bearer_id, &xmitq, &e->maddr, NULL);
	}

	rcu_read_unlock();
}


static void tipc_node_mcast_rcv(struct tipc_node *n)
{
	struct tipc_bclink_entry *be = &n->bc_entry;

	/* 'arrvq' is under inputq2's lock protection */
	spin_lock_bh(&be->inputq2.lock);
	spin_lock_bh(&be->inputq1.lock);
	skb_queue_splice_tail_init(&be->inputq1, &be->arrvq);
	spin_unlock_bh(&be->inputq1.lock);
	spin_unlock_bh(&be->inputq2.lock);
	tipc_sk_mcast_rcv(n->net, &be->arrvq, &be->inputq2);
}


static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
				    struct tipc_node *node, u32 *prev_link,
				    bool bc_link)
{
	u32 i;
	int err;

	for (i = *prev_link; i < MAX_BEARERS; i++) {
		*prev_link = i;

		if (!node->links[i].link)
			continue;

		err = __tipc_nl_add_link(net, msg,
					 node->links[i].link, NLM_F_MULTI);
		if (err)
			return err;
	}

	if (bc_link) {
		*prev_link = i;
		err = tipc_nl_add_bc_link(net, msg, node->bc_entry.link);
		if (err)
			return err;
	}

	*prev_link = 0;

	return 0;
}


static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id)
{
	int rc;
	struct sk_buff_head xmitq;
	struct tipc_bclink_entry *be;
	struct tipc_link_entry *le;
	struct tipc_msg *hdr = buf_msg(skb);
	int usr = msg_user(hdr);
	u32 dnode = msg_destnode(hdr);
	struct tipc_node *n;

	__skb_queue_head_init(&xmitq);

	/* If NACK for other node, let rcv link for that node peek into it */
	if ((usr == BCAST_PROTOCOL) && (dnode != tipc_own_addr(net)))
		n = tipc_node_find(net, dnode);
	else
		n = tipc_node_find(net, msg_prevnode(hdr));
	if (!n) {
		kfree_skb(skb);
		return;
	}
	be = &n->bc_entry;
	le = &n->links[bearer_id];

	rc = tipc_bcast_rcv(net, be->link, skb);

	/* Broadcast ACKs are sent on a unicast link */
	if (rc & TIPC_LINK_SND_STATE) {
		tipc_node_read_lock(n);
		tipc_link_build_state_msg(le->link, &xmitq);
		tipc_node_read_unlock(n);
	}

	if (!skb_queue_empty(&xmitq))
		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);

	if (!skb_queue_empty(&be->inputq1))
		tipc_node_mcast_rcv(n);

	/* Handle NAME_DISTRIBUTOR messages sent from 1.7 nodes */
	if (!skb_queue_empty(&n->bc_entry.namedq))
		tipc_named_rcv(net, &n->bc_entry.namedq,
			       &n->bc_entry.named_rcv_nxt,
			       &n->bc_entry.named_open);

	/* If reassembly or retransmission failure => reset all links to peer */
	if (rc & TIPC_LINK_DOWN_EVT)
		tipc_node_reset_links(n);

	tipc_node_put(n);
}


struct tipc_crypto *tipc_node_crypto_rx_by_addr(struct net *net, u32 addr)
{
	struct tipc_node *n;

	n = tipc_node_find(net, addr);
	return (n) ? n->crypto_rx : NULL;
}


int tipc_nl_node_flush_key(struct sk_buff *skb, struct genl_info *info)
{
	int err;

	rtnl_lock();
	err = __tipc_nl_node_flush_key(skb, info);
	rtnl_unlock();

	return err;
}


struct tipc_node *tipc_node_create(struct net *net, u32 addr, u8 *peer_id,
				   u16 capabilities, u32 hash_mixes,
				   bool preliminary)
{
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	struct tipc_node *n, *temp_node;
	struct tipc_link *l;
	unsigned long intv;
	int bearer_id;
	int i;

	spin_lock_bh(&tn->node_list_lock);
	n = tipc_node_find(net, addr) ?:
		tipc_node_find_by_id(net, peer_id);
	if (n) {
		if (!n->preliminary)
			goto update;
		if (preliminary)
			goto exit;
		/* A preliminary node becomes "real" now, refresh its data */
		tipc_node_write_lock(n);
		n->preliminary = false;
		n->addr = addr;
		hlist_del_rcu(&n->hash);
		hlist_add_head_rcu(&n->hash,
				   &tn->node_htable[tipc_hashfn(addr)]);
		list_del_rcu(&n->list);
		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
			if (n->addr < temp_node->addr)
				break;
		}
		list_add_tail_rcu(&n->list, &temp_node->list);
		tipc_node_write_unlock_fast(n);

update:
		if (n->peer_hash_mix ^ hash_mixes)
			tipc_node_assign_peer_net(n, hash_mixes);
		if (n->capabilities == capabilities)
			goto exit;
		/* Same node may come back with new capabilities */
		tipc_node_write_lock(n);
		n->capabilities = capabilities;
		for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
			l = n->links[bearer_id].link;
			if (l)
				tipc_link_update_caps(l, capabilities);
		}
		tipc_node_write_unlock_fast(n);

		/* Calculate cluster capabilities */
		tn->capabilities = TIPC_NODE_CAPABILITIES;
		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
			tn->capabilities &= temp_node->capabilities;
		}

		tipc_bcast_toggle_rcast(net,
					(tn->capabilities & TIPC_BCAST_RCAST));

		goto exit;
	}
	n = kzalloc(sizeof(*n), GFP_ATOMIC);
	if (!n) {
		pr_warn("Node creation failed, no memory\n");
		goto exit;
	}
	tipc_nodeid2string(n->peer_id_string, peer_id);
#ifdef CONFIG_TIPC_CRYPTO
	if (unlikely(tipc_crypto_start(&n->crypto_rx, net, n))) {
		pr_warn("Failed to start crypto RX(%s)!\n", n->peer_id_string);
		kfree(n);
		n = NULL;
		goto exit;
	}
#endif
	n->addr = addr;
	n->preliminary = preliminary;
	memcpy(&n->peer_id, peer_id, 16);
	n->net = net;
	n->peer_net = NULL;
	n->peer_hash_mix = 0;
	/* Assign kernel local namespace if exists */
	tipc_node_assign_peer_net(n, hash_mixes);
	n->capabilities = capabilities;
	kref_init(&n->kref);
	rwlock_init(&n->lock);
	INIT_HLIST_NODE(&n->hash);
	INIT_LIST_HEAD(&n->list);
	INIT_LIST_HEAD(&n->publ_list);
	INIT_LIST_HEAD(&n->conn_sks);
	skb_queue_head_init(&n->bc_entry.namedq);
	skb_queue_head_init(&n->bc_entry.inputq1);
	__skb_queue_head_init(&n->bc_entry.arrvq);
	skb_queue_head_init(&n->bc_entry.inputq2);
	for (i = 0; i < MAX_BEARERS; i++)
		spin_lock_init(&n->links[i].lock);
	n->state = SELF_DOWN_PEER_LEAVING;
	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
	n->signature = INVALID_NODE_SIG;
	n->active_links[0] = INVALID_BEARER_ID;
	n->active_links[1] = INVALID_BEARER_ID;
	n->bc_entry.link = NULL;
	tipc_node_get(n);
	timer_setup(&n->timer, tipc_node_timeout, 0);
	/* Start a slow timer anyway, crypto needs it */
	n->keepalive_intv = 10000;
	intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
	if (!mod_timer(&n->timer, intv))
		tipc_node_get(n);
	hlist_add_head_rcu(&n->hash, &tn->node_htable[tipc_hashfn(addr)]);
	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
		if (n->addr < temp_node->addr)
			break;
	}
	list_add_tail_rcu(&n->list, &temp_node->list);
	/* Calculate cluster capabilities */
	tn->capabilities = TIPC_NODE_CAPABILITIES;
	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
		tn->capabilities &= temp_node->capabilities;
	}
	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
	trace_tipc_node_create(n, true, " ");
exit:
	spin_unlock_bh(&tn->node_list_lock);
	return n;
}


static void tipc_node_link_failover(struct tipc_node *n, struct tipc_link *l,
				    struct tipc_link *tnl,
				    struct sk_buff_head *xmitq)
{
	/* Avoid to be "self-failover" that can never end */
	if (!tipc_link_is_up(tnl))
		return;

	/* Don't rush, failure link may be in the process of resetting */
	if (l && !tipc_link_is_reset(l))
		return;

	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);

	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
	tipc_link_failover_prepare(l, tnl, xmitq);

	if (l)
		tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
}


static void tipc_node_assign_peer_net(struct tipc_node *n, u32 hash_mixes)
{
	int net_id = tipc_netid(n->net);
	struct tipc_net *tn_peer;
	struct net *tmp;
	u32 hash_chk;

	if (n->peer_net)
		return;

	for_each_net_rcu(tmp) {
		tn_peer = tipc_net(tmp);
		if (!tn_peer)
			continue;
		/* Integrity checking whether node exists in namespace or not */
		if (tn_peer->net_id != net_id)
			continue;
		if (memcmp(n->peer_id, tn_peer->node_id, NODE_ID_LEN))
			continue;
		hash_chk = tipc_net_hash_mixes(tmp, tn_peer->random);
		if (hash_mixes ^ hash_chk)
			continue;
		n->peer_net = tmp;
		n->peer_hash_mix = hash_mixes;
		break;
	}
}


static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
{
	struct tipc_link_entry *le = &n->links[bearer_id];
	struct tipc_media_addr *maddr = NULL;
	struct tipc_link *l = le->link;
	int old_bearer_id = bearer_id;
	struct sk_buff_head xmitq;

	if (!l)
		return;

	__skb_queue_head_init(&xmitq);

	tipc_node_write_lock(n);
	if (!tipc_link_is_establishing(l)) {
		__tipc_node_link_down(n, &bearer_id, &xmitq, &maddr);
	} else {
		/* Defuse pending tipc_node_link_up() */
		tipc_link_reset(l);
		tipc_link_fsm_evt(l, LINK_RESET_EVT);
	}
	if (delete) {
		kfree(l);
		le->link = NULL;
		n->link_cnt--;
	}
	trace_tipc_node_link_down(n, true, "node link down or deleted!");
	tipc_node_write_unlock(n);
	if (delete)
		tipc_mon_remove_peer(n->net, n->addr, old_bearer_id);
	if (!skb_queue_empty(&xmitq))
		tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr, n);
	tipc_sk_rcv(n->net, &le->inputq);
}


static void tipc_node_write_unlock(struct tipc_node *n)
{
	struct net *net = n->net;
	u32 addr = 0;
	u32 flags = n->action_flags;
	u32 link_id = 0;
	u32 bearer_id;
	struct list_head *publ_list;

	if (likely(!flags)) {
		write_unlock_bh(&n->lock);
		return;
	}

	addr = n->addr;
	link_id = n->link_id;
	bearer_id = link_id & 0xffff;
	publ_list = &n->publ_list;

	n->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
			     TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP);

	write_unlock_bh(&n->lock);

	if (flags & TIPC_NOTIFY_NODE_DOWN)
		tipc_publ_notify(net, publ_list, addr, n->capabilities);

	if (flags & TIPC_NOTIFY_NODE_UP)
		tipc_named_node_up(net, addr, n->capabilities);

	if (flags & TIPC_NOTIFY_LINK_UP) {
		tipc_mon_peer_up(net, addr, bearer_id);
		tipc_nametbl_publish(net, TIPC_LINK_STATE, addr, addr,
				     TIPC_NODE_SCOPE, link_id, link_id);
	}
	if (flags & TIPC_NOTIFY_LINK_DOWN) {
		tipc_mon_peer_down(net, addr, bearer_id);
		tipc_nametbl_withdraw(net, TIPC_LINK_STATE, addr,
				      addr, link_id);
	}
}


void tipc_node_stop(struct net *net)
{
	struct tipc_net *tn = tipc_net(net);
	struct tipc_node *node, *t_node;

	spin_lock_bh(&tn->node_list_lock);
	list_for_each_entry_safe(node, t_node, &tn->node_list, list)
		tipc_node_delete(node);
	spin_unlock_bh(&tn->node_list_lock);
}


int tipc_node_distr_xmit(struct net *net, struct sk_buff_head *xmitq)
{
	struct sk_buff *skb;
	u32 selector, dnode;

	while ((skb = __skb_dequeue(xmitq))) {
		selector = msg_origport(buf_msg(skb));
		dnode = msg_destnode(buf_msg(skb));
		tipc_node_xmit_skb(net, skb, dnode, selector);
	}
	return 0;
}


u32 tipc_node_get_addr(struct tipc_node *node)
{
	return (node) ? node->addr : 0;
}


void tipc_node_broadcast(struct net *net, struct sk_buff *skb, int rc_dests)
{
	struct sk_buff_head xmitq;
	struct sk_buff *txskb;
	struct tipc_node *n;
	u16 dummy;
	u32 dst;

	/* Use broadcast if all nodes support it */
	if (!rc_dests && tipc_bcast_get_mode(net) != BCLINK_MODE_RCAST) {
		__skb_queue_head_init(&xmitq);
		__skb_queue_tail(&xmitq, skb);
		tipc_bcast_xmit(net, &xmitq, &dummy);
		return;
	}

	/* Otherwise use legacy replicast method */
	rcu_read_lock();
	list_for_each_entry_rcu(n, tipc_nodes(net), list) {
		dst = n->addr;
		if (in_own_node(net, dst))
			continue;
		if (!node_is_up(n))
			continue;
		txskb = pskb_copy(skb, GFP_ATOMIC);
		if (!txskb)
			break;
		msg_set_destnode(buf_msg(txskb), dst);
		tipc_node_xmit_skb(net, txskb, dst, 0);
	}
	rcu_read_unlock();
	kfree_skb(skb);
}


static void tipc_node_read_lock(struct tipc_node *n)
{
	read_lock_bh(&n->lock);
}


int tipc_nl_node_dump_monitor(struct sk_buff *skb, struct netlink_callback *cb)
{
	struct net *net = sock_net(skb->sk);
	u32 prev_bearer = cb->args[0];
	struct tipc_nl_msg msg;
	int bearer_id;
	int err;

	if (prev_bearer == MAX_BEARERS)
		return 0;

	msg.skb = skb;
	msg.portid = NETLINK_CB(cb->skb).portid;
	msg.seq = cb->nlh->nlmsg_seq;

	rtnl_lock();
	for (bearer_id = prev_bearer; bearer_id < MAX_BEARERS; bearer_id++) {
		err = __tipc_nl_add_monitor(net, &msg, bearer_id);
		if (err)
			break;
	}
	rtnl_unlock();
	cb->args[0] = bearer_id;

	return skb->len;
}


static struct tipc_node *tipc_node_find(struct net *net, u32 addr)
{
	struct tipc_net *tn = tipc_net(net);
	struct tipc_node *node;
	unsigned int thash = tipc_hashfn(addr);

	rcu_read_lock();
	hlist_for_each_entry_rcu(node, &tn->node_htable[thash], hash) {
		if (node->addr != addr || node->preliminary)
			continue;
		if (!kref_get_unless_zero(&node->kref))
			node = NULL;
		break;
	}
	rcu_read_unlock();
	return node;
}


static int __tipc_nl_node_flush_key(struct sk_buff *skb,
				    struct genl_info *info)
{
	struct net *net = sock_net(skb->sk);
	struct tipc_net *tn = tipc_net(net);
	struct tipc_node *n;

	tipc_crypto_key_flush(tn->crypto_tx);
	rcu_read_lock();
	list_for_each_entry_rcu(n, &tn->node_list, list)
		tipc_crypto_key_flush(n->crypto_rx);
	rcu_read_unlock();

	return 0;
}


static void tipc_node_link_up(struct tipc_node *n, int bearer_id,
			      struct sk_buff_head *xmitq)
{
	struct tipc_media_addr *maddr;

	tipc_node_write_lock(n);
	__tipc_node_link_up(n, bearer_id, xmitq);
	maddr = &n->links[bearer_id].maddr;
	tipc_bearer_xmit(n->net, bearer_id, xmitq, maddr, n);
	tipc_node_write_unlock(n);
}


static bool tipc_node_cleanup(struct tipc_node *peer)
{
	struct tipc_node *temp_node;
	struct tipc_net *tn = tipc_net(peer->net);
	bool deleted = false;

	/* If lock held by tipc_node_stop() the node will be deleted anyway */
	if (!spin_trylock_bh(&tn->node_list_lock))
		return false;

	tipc_node_write_lock(peer);

	if (!node_is_up(peer) && time_after(jiffies, peer->delete_at)) {
		tipc_node_clear_links(peer);
		tipc_node_delete_from_list(peer);
		deleted = true;
	}
	tipc_node_write_unlock(peer);

	if (!deleted) {
		spin_unlock_bh(&tn->node_list_lock);
		return deleted;
	}

	/* Calculate cluster capabilities */
	tn->capabilities = TIPC_NODE_CAPABILITIES;
	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
		tn->capabilities &= temp_node->capabilities;
	}
	tipc_bcast_toggle_rcast(peer->net,
				(tn->capabilities & TIPC_BCAST_RCAST));
	spin_unlock_bh(&tn->node_list_lock);
	return deleted;
}


static void tipc_node_bc_sync_rcv(struct tipc_node *n, struct tipc_msg *hdr,
				  int bearer_id, struct sk_buff_head *xmitq)
{
	struct tipc_link *ucl;
	int rc;

	rc = tipc_bcast_sync_rcv(n->net, n->bc_entry.link, hdr, xmitq);

	if (rc & TIPC_LINK_DOWN_EVT) {
		tipc_node_reset_links(n);
		return;
	}

	if (!(rc & TIPC_LINK_SND_STATE))
		return;

	/* If probe message, a STATE response will be sent anyway */
	if (msg_probe(hdr))
		return;

	/* Produce a STATE message carrying broadcast NACK */
	tipc_node_read_lock(n);
	ucl = n->links[bearer_id].link;
	if (ucl)
		tipc_link_build_state_msg(ucl, xmitq);
	tipc_node_read_unlock(n);
}


int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel, bool connected)
{
	struct tipc_node *n;
	int bearer_id;
	unsigned int mtu = MAX_MSG_SIZE;

	n = tipc_node_find(net, addr);
	if (unlikely(!n))
		return mtu;

	/* Allow MAX_MSG_SIZE when building connection oriented message
	 * if they are in the same core network
	 */
	if (n->peer_net && connected) {
		tipc_node_put(n);
		return mtu;
	}

	bearer_id = n->active_links[sel & 1];
	if (likely(bearer_id != INVALID_BEARER_ID))
		mtu = n->links[bearer_id].mtu;
	tipc_node_put(n);
	return mtu;
}


static bool node_is_up(struct tipc_node *n)
{
	return n->active_links[0] != INVALID_BEARER_ID;
}


bool tipc_node_is_up(struct net *net, u32 addr)
{
	struct tipc_node *n;
	bool retval = false;

	if (in_own_node(net, addr))
		return true;

	n = tipc_node_find(net, addr);
	if (!n)
		return false;
	retval = node_is_up(n);
	tipc_node_put(n);
	return retval;
}


int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb)
{
	struct net *net = sock_net(skb->sk);
	struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
	struct nlattr *link[TIPC_NLA_LINK_MAX + 1];
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	struct tipc_node *node;
	struct tipc_nl_msg msg;
	u32 prev_node = cb->args[0];
	u32 prev_link = cb->args[1];
	int done = cb->args[2];
	bool bc_link = cb->args[3];
	int err;

	if (done)
		return 0;

	if (!prev_node) {
		/* Check if broadcast-receiver links dumping is needed */
		if (attrs && attrs[TIPC_NLA_LINK]) {
			err = nla_parse_nested_deprecated(link,
							  TIPC_NLA_LINK_MAX,
							  attrs[TIPC_NLA_LINK],
							  tipc_nl_link_policy,
							  NULL);
			if (unlikely(err))
				return err;
			if (unlikely(!link[TIPC_NLA_LINK_BROADCAST]))
				return -EINVAL;
			bc_link = true;
		}
	}

	msg.skb = skb;
	msg.portid = NETLINK_CB(cb->skb).portid;
	msg.seq = cb->nlh->nlmsg_seq;

	rcu_read_lock();
	if (prev_node) {
		node = tipc_node_find(net, prev_node);
		if (!node) {
			/* We never set seq or call nl_dump_check_consistent()
			 * this means that setting prev_seq here will cause the
			 * consistence check to fail in the netlink callback
			 * handler. Resulting in the last NLMSG_DONE message
			 * having the NLM_F_DUMP_INTR flag set.
			 */
			cb->prev_seq = 1;
			goto out;
		}
		tipc_node_put(node);

		list_for_each_entry_continue_rcu(node, &tn->node_list,
						 list) {
			tipc_node_read_lock(node);
			err = __tipc_nl_add_node_links(net, &msg, node,
						       &prev_link, bc_link);
			tipc_node_read_unlock(node);
			if (err)
				goto out;

			prev_node = node->addr;
		}
	} else {
		err = tipc_nl_add_bc_link(net, &msg, tn->bcl);
		if (err)
			goto out;

		list_for_each_entry_rcu(node, &tn->node_list, list) {
			tipc_node_read_lock(node);
			err = __tipc_nl_add_node_links(net, &msg, node,
						       &prev_link, bc_link);
			tipc_node_read_unlock(node);
			if (err)
				goto out;

			prev_node = node->addr;
		}
	}
	done = 1;
out:
	rcu_read_unlock();

	cb->args[0] = prev_node;
	cb->args[1] = prev_link;
	cb->args[2] = done;
	cb->args[3] = bc_link;

	return skb->len;
}


static int tipc_nl_retrieve_rekeying(struct nlattr **attrs, u32 *intv)
{
	struct nlattr *attr = attrs[TIPC_NLA_NODE_REKEYING];

	if (!attr)
		return -ENODATA;

	*intv = nla_get_u32(attr);
	return 0;
}


void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
{
	struct tipc_node *n;

	if (in_own_node(net, addr))
		return;

	n = tipc_node_find(net, addr);
	if (!n) {
		pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr);
		return;
	}
	tipc_node_write_lock(n);
	list_add_tail(subscr, &n->publ_list);
	tipc_node_write_unlock_fast(n);
	tipc_node_put(n);
}


static void  tipc_node_clear_links(struct tipc_node *node)
{
	int i;

	for (i = 0; i < MAX_BEARERS; i++) {
		struct tipc_link_entry *le = &node->links[i];

		if (le->link) {
			kfree(le->link);
			le->link = NULL;
			node->link_cnt--;
		}
	}
}


void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
{
	struct tipc_node *node;
	struct tipc_sock_conn *conn, *safe;

	if (in_own_node(net, dnode))
		return;

	node = tipc_node_find(net, dnode);
	if (!node)
		return;

	tipc_node_write_lock(node);
	list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
		if (port != conn->port)
			continue;
		list_del(&conn->list);
		kfree(conn);
	}
	tipc_node_write_unlock(node);
	tipc_node_put(node);
}


static void tipc_node_kref_release(struct kref *kref)
{
	struct tipc_node *n = container_of(kref, struct tipc_node, kref);

	kfree(n->bc_entry.link);
	call_rcu(&n->rcu, tipc_node_free);
}


char *tipc_node_get_id_str(struct tipc_node *node)
{
	return node->peer_id_string;
}


int tipc_nl_node_set_monitor(struct sk_buff *skb, struct genl_info *info)
{
	struct nlattr *attrs[TIPC_NLA_MON_MAX + 1];
	struct net *net = sock_net(skb->sk);
	int err;

	if (!info->attrs[TIPC_NLA_MON])
		return -EINVAL;

	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MON_MAX,
					  info->attrs[TIPC_NLA_MON],
					  tipc_nl_monitor_policy,
					  info->extack);
	if (err)
		return err;

	if (attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]) {
		u32 val;

		val = nla_get_u32(attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]);
		err = tipc_nl_monitor_set_threshold(net, val);
		if (err)
			return err;
	}

	return 0;
}


struct tipc_crypto *tipc_node_crypto_rx(struct tipc_node *__n)
{
	return (__n) ? __n->crypto_rx : NULL;
}


static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id)
{
	struct tipc_net *tn = tipc_net(net);
	struct tipc_node *n;
	bool found = false;

	rcu_read_lock();
	list_for_each_entry_rcu(n, &tn->node_list, list) {
		read_lock_bh(&n->lock);
		if (!memcmp(id, n->peer_id, 16) &&
		    kref_get_unless_zero(&n->kref))
			found = true;
		read_unlock_bh(&n->lock);
		if (found)
			break;
	}
	rcu_read_unlock();
	return found ? n : NULL;
}


int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
			   char *linkname, size_t len)
{
	struct tipc_link *link;
	int err = -EINVAL;
	struct tipc_node *node = tipc_node_find(net, addr);

	if (!node)
		return err;

	if (bearer_id >= MAX_BEARERS)
		goto exit;

	tipc_node_read_lock(node);
	link = node->links[bearer_id].link;
	if (link) {
		strncpy(linkname, tipc_link_name(link), len);
		err = 0;
	}
	tipc_node_read_unlock(node);
exit:
	tipc_node_put(node);
	return err;
}


static void tipc_node_read_unlock(struct tipc_node *n)
{
	read_unlock_bh(&n->lock);
}


static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
				struct sk_buff_head *xmitq)
{
	int *slot0 = &n->active_links[0];
	int *slot1 = &n->active_links[1];
	struct tipc_link *ol = node_active_link(n, 0);
	struct tipc_link *nl = n->links[bearer_id].link;

	if (!nl || tipc_link_is_up(nl))
		return;

	tipc_link_fsm_evt(nl, LINK_ESTABLISH_EVT);
	if (!tipc_link_is_up(nl))
		return;

	n->working_links++;
	n->action_flags |= TIPC_NOTIFY_LINK_UP;
	n->link_id = tipc_link_id(nl);

	/* Leave room for tunnel header when returning 'mtu' to users: */
	n->links[bearer_id].mtu = tipc_link_mss(nl);

	tipc_bearer_add_dest(n->net, bearer_id, n->addr);
	tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id);

	pr_debug("Established link <%s> on network plane %c\n",
		 tipc_link_name(nl), tipc_link_plane(nl));
	trace_tipc_node_link_up(n, true, " ");

	/* Ensure that a STATE message goes first */
	tipc_link_build_state_msg(nl, xmitq);

	/* First link? => give it both slots */
	if (!ol) {
		*slot0 = bearer_id;
		*slot1 = bearer_id;
		tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT);
		n->action_flags |= TIPC_NOTIFY_NODE_UP;
		tipc_link_set_active(nl, true);
		tipc_bcast_add_peer(n->net, nl, xmitq);
		return;
	}

	/* Second link => redistribute slots */
	if (tipc_link_prio(nl) > tipc_link_prio(ol)) {
		pr_debug("Old link <%s> becomes standby\n", tipc_link_name(ol));
		*slot0 = bearer_id;
		*slot1 = bearer_id;
		tipc_link_set_active(nl, true);
		tipc_link_set_active(ol, false);
	} else if (tipc_link_prio(nl) == tipc_link_prio(ol)) {
		tipc_link_set_active(nl, true);
		*slot1 = bearer_id;
	} else {
		pr_debug("New link <%s> is standby\n", tipc_link_name(nl));
	}

	/* Prepare synchronization with first link */
	tipc_link_tnl_prepare(ol, nl, SYNCH_MSG, xmitq);
}


u16 tipc_node_get_capabilities(struct net *net, u32 addr)
{
	struct tipc_node *n;
	u16 caps;

	n = tipc_node_find(net, addr);
	if (unlikely(!n))
		return TIPC_NODE_CAPABILITIES;
	caps = n->capabilities;
	tipc_node_put(n);
	return caps;
}


void tipc_node_check_dest(struct net *net, u32 addr,
			  u8 *peer_id, struct tipc_bearer *b,
			  u16 capabilities, u32 signature, u32 hash_mixes,
			  struct tipc_media_addr *maddr,
			  bool *respond, bool *dupl_addr)
{
	struct tipc_node *n;
	struct tipc_link *l, *snd_l;
	struct tipc_link_entry *le;
	bool addr_match = false;
	bool sign_match = false;
	bool link_up = false;
	bool accept_addr = false;
	bool reset = true;
	char *if_name;
	unsigned long intv;
	u16 session;

	*dupl_addr = false;
	*respond = false;

	n = tipc_node_create(net, addr, peer_id, capabilities, hash_mixes,
			     false);
	if (!n)
		return;

	tipc_node_write_lock(n);
	if (unlikely(!n->bc_entry.link)) {
		snd_l = tipc_bc_sndlink(net);
		if (!tipc_link_bc_create(net, tipc_own_addr(net),
					 addr, peer_id, U16_MAX,
					 tipc_link_min_win(snd_l),
					 tipc_link_max_win(snd_l),
					 n->capabilities,
					 &n->bc_entry.inputq1,
					 &n->bc_entry.namedq, snd_l,
					 &n->bc_entry.link)) {
			pr_warn("Broadcast rcv link creation failed, no mem\n");
			tipc_node_write_unlock_fast(n);
			tipc_node_put(n);
			return;
		}
	}

	le = &n->links[b->identity];

	/* Prepare to validate requesting node's signature and media address */
	l = le->link;
	link_up = l && tipc_link_is_up(l);
	addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr));
	sign_match = (signature == n->signature);

	/* These three flags give us eight permutations: */

	if (sign_match && addr_match && link_up) {
		/* All is fine. Do nothing. */
		reset = false;
		/* Peer node is not a container/local namespace */
		if (!n->peer_hash_mix)
			n->peer_hash_mix = hash_mixes;
	} else if (sign_match && addr_match && !link_up) {
		/* Respond. The link will come up in due time */
		*respond = true;
	} else if (sign_match && !addr_match && link_up) {
		/* Peer has changed i/f address without rebooting.
		 * If so, the link will reset soon, and the next
		 * discovery will be accepted. So we can ignore it.
		 * It may also be an cloned or malicious peer having
		 * chosen the same node address and signature as an
		 * existing one.
		 * Ignore requests until the link goes down, if ever.
		 */
		*dupl_addr = true;
	} else if (sign_match && !addr_match && !link_up) {
		/* Peer link has changed i/f address without rebooting.
		 * It may also be a cloned or malicious peer; we can't
		 * distinguish between the two.
		 * The signature is correct, so we must accept.
		 */
		accept_addr = true;
		*respond = true;
	} else if (!sign_match && addr_match && link_up) {
		/* Peer node rebooted. Two possibilities:
		 *  - Delayed re-discovery; this link endpoint has already
		 *    reset and re-established contact with the peer, before
		 *    receiving a discovery message from that node.
		 *    (The peer happened to receive one from this node first).
		 *  - The peer came back so fast that our side has not
		 *    discovered it yet. Probing from this side will soon
		 *    reset the link, since there can be no working link
		 *    endpoint at the peer end, and the link will re-establish.
		 *  Accept the signature, since it comes from a known peer.
		 */
		n->signature = signature;
	} else if (!sign_match && addr_match && !link_up) {
		/*  The peer node has rebooted.
		 *  Accept signature, since it is a known peer.
		 */
		n->signature = signature;
		*respond = true;
	} else if (!sign_match && !addr_match && link_up) {
		/* Peer rebooted with new address, or a new/duplicate peer.
		 * Ignore until the link goes down, if ever.
		 */
		*dupl_addr = true;
	} else if (!sign_match && !addr_match && !link_up) {
		/* Peer rebooted with new address, or it is a new peer.
		 * Accept signature and address.
		 */
		n->signature = signature;
		accept_addr = true;
		*respond = true;
	}

	if (!accept_addr)
		goto exit;

	/* Now create new link if not already existing */
	if (!l) {
		if (n->link_cnt == 2)
			goto exit;

		if_name = strchr(b->name, ':') + 1;
		get_random_bytes(&session, sizeof(u16));
		if (!tipc_link_create(net, if_name, b->identity, b->tolerance,
				      b->net_plane, b->mtu, b->priority,
				      b->min_win, b->max_win, session,
				      tipc_own_addr(net), addr, peer_id,
				      n->capabilities,
				      tipc_bc_sndlink(n->net), n->bc_entry.link,
				      &le->inputq,
				      &n->bc_entry.namedq, &l)) {
			*respond = false;
			goto exit;
		}
		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link created!");
		tipc_link_reset(l);
		tipc_link_fsm_evt(l, LINK_RESET_EVT);
		if (n->state == NODE_FAILINGOVER)
			tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
		le->link = l;
		n->link_cnt++;
		tipc_node_calculate_timer(n, l);
		if (n->link_cnt == 1) {
			intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
			if (!mod_timer(&n->timer, intv))
				tipc_node_get(n);
		}
	}
	memcpy(&le->maddr, maddr, sizeof(*maddr));
exit:
	tipc_node_write_unlock(n);
	if (reset && l && !tipc_link_is_reset(l))
		tipc_node_link_down(n, b->identity, false);
	tipc_node_put(n);
}


int tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
{
	int err;

	rtnl_lock();
	err = __tipc_nl_node_set_key(skb, info);
	rtnl_unlock();

	return err;
}


static void tipc_lxc_xmit(struct net *peer_net, struct sk_buff_head *list)
{
	struct tipc_msg *hdr = buf_msg(skb_peek(list));
	struct sk_buff_head inputq;

	switch (msg_user(hdr)) {
	case TIPC_LOW_IMPORTANCE:
	case TIPC_MEDIUM_IMPORTANCE:
	case TIPC_HIGH_IMPORTANCE:
	case TIPC_CRITICAL_IMPORTANCE:
		if (msg_connected(hdr) || msg_named(hdr) ||
		    msg_direct(hdr)) {
			tipc_loopback_trace(peer_net, list);
			spin_lock_init(&list->lock);
			tipc_sk_rcv(peer_net, list);
			return;
		}
		if (msg_mcast(hdr)) {
			tipc_loopback_trace(peer_net, list);
			skb_queue_head_init(&inputq);
			tipc_sk_mcast_rcv(peer_net, list, &inputq);
			__skb_queue_purge(list);
			skb_queue_purge(&inputq);
			return;
		}
		return;
	case MSG_FRAGMENTER:
		if (tipc_msg_assemble(list)) {
			tipc_loopback_trace(peer_net, list);
			skb_queue_head_init(&inputq);
			tipc_sk_mcast_rcv(peer_net, list, &inputq);
			__skb_queue_purge(list);
			skb_queue_purge(&inputq);
		}
		return;
	case GROUP_PROTOCOL:
	case CONN_MANAGER:
		tipc_loopback_trace(peer_net, list);
		spin_lock_init(&list->lock);
		tipc_sk_rcv(peer_net, list);
		return;
	case LINK_PROTOCOL:
	case NAME_DISTRIBUTOR:
	case TUNNEL_PROTOCOL:
	case BCAST_PROTOCOL:
		return;
	default:
		return;
	}
}


static int __tipc_nl_add_monitor_prop(struct net *net, struct tipc_nl_msg *msg)
{
	struct nlattr *attrs;
	void *hdr;
	u32 val;

	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
			  0, TIPC_NL_MON_GET);
	if (!hdr)
		return -EMSGSIZE;

	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MON);
	if (!attrs)
		goto msg_full;

	val = tipc_nl_monitor_get_threshold(net);

	if (nla_put_u32(msg->skb, TIPC_NLA_MON_ACTIVATION_THRESHOLD, val))
		goto attr_msg_full;

	nla_nest_end(msg->skb, attrs);
	genlmsg_end(msg->skb, hdr);

	return 0;

attr_msg_full:
	nla_nest_cancel(msg->skb, attrs);
msg_full:
	genlmsg_cancel(msg->skb, hdr);

	return -EMSGSIZE;
}


int tipc_nl_node_dump_monitor_peer(struct sk_buff *skb,
				   struct netlink_callback *cb)
{
	struct net *net = sock_net(skb->sk);
	u32 prev_node = cb->args[1];
	u32 bearer_id = cb->args[2];
	int done = cb->args[0];
	struct tipc_nl_msg msg;
	int err;

	if (!prev_node) {
		struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
		struct nlattr *mon[TIPC_NLA_MON_MAX + 1];

		if (!attrs[TIPC_NLA_MON])
			return -EINVAL;

		err = nla_parse_nested_deprecated(mon, TIPC_NLA_MON_MAX,
						  attrs[TIPC_NLA_MON],
						  tipc_nl_monitor_policy,
						  NULL);
		if (err)
			return err;

		if (!mon[TIPC_NLA_MON_REF])
			return -EINVAL;

		bearer_id = nla_get_u32(mon[TIPC_NLA_MON_REF]);

		if (bearer_id >= MAX_BEARERS)
			return -EINVAL;
	}

	if (done)
		return 0;

	msg.skb = skb;
	msg.portid = NETLINK_CB(cb->skb).portid;
	msg.seq = cb->nlh->nlmsg_seq;

	rtnl_lock();
	err = tipc_nl_add_monitor_peer(net, &msg, bearer_id, &prev_node);
	if (!err)
		done = 1;

	rtnl_unlock();
	cb->args[0] = done;
	cb->args[1] = prev_node;
	cb->args[2] = bearer_id;

	return skb->len;
}


static void tipc_node_reset_links(struct tipc_node *n)
{
	int i;

	pr_warn("Resetting all links to %x\n", n->addr);

	trace_tipc_node_reset_links(n, true, " ");
	for (i = 0; i < MAX_BEARERS; i++) {
		tipc_node_link_down(n, i, false);
	}
}


static u32 tipc_node_suggest_addr(struct net *net, u32 addr)
{
	struct tipc_node *n;

	addr ^= tipc_net(net)->random;
	while ((n = tipc_node_find(net, addr))) {
		tipc_node_put(n);
		addr++;
	}
	return addr;
}


static void tipc_node_write_lock(struct tipc_node *n)
{
	write_lock_bh(&n->lock);
}


static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
{
	unsigned long tol = tipc_link_tolerance(l);
	unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;

	/* Link with lowest tolerance determines timer interval */
	if (intv < n->keepalive_intv)
		n->keepalive_intv = intv;

	/* Ensure link's abort limit corresponds to current tolerance */
	tipc_link_set_abort_limit(l, tol / n->keepalive_intv);
}


static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
				  int bearer_id, struct sk_buff_head *xmitq)
{
	struct tipc_msg *hdr = buf_msg(skb);
	int usr = msg_user(hdr);
	int mtyp = msg_type(hdr);
	u16 oseqno = msg_seqno(hdr);
	u16 exp_pkts = msg_msgcnt(hdr);
	u16 rcv_nxt, syncpt, dlv_nxt, inputq_len;
	int state = n->state;
	struct tipc_link *l, *tnl, *pl = NULL;
	struct tipc_media_addr *maddr;
	int pb_id;

	if (trace_tipc_node_check_state_enabled()) {
		trace_tipc_skb_dump(skb, false, "skb for node state check");
		trace_tipc_node_check_state(n, true, " ");
	}
	l = n->links[bearer_id].link;
	if (!l)
		return false;
	rcv_nxt = tipc_link_rcv_nxt(l);

	if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL)))
		return true;

	/* Find parallel link, if any */
	for (pb_id = 0; pb_id < MAX_BEARERS; pb_id++) {
		if ((pb_id != bearer_id) && n->links[pb_id].link) {
			pl = n->links[pb_id].link;
			break;
		}
	}

	if (!tipc_link_validate_msg(l, hdr)) {
		trace_tipc_skb_dump(skb, false, "PROTO invalid (2)!");
		trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (2)!");
		return false;
	}

	/* Check and update node accesibility if applicable */
	if (state == SELF_UP_PEER_COMING) {
		if (!tipc_link_is_up(l))
			return true;
		if (!msg_peer_link_is_up(hdr))
			return true;
		tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT);
	}

	if (state == SELF_DOWN_PEER_LEAVING) {
		if (msg_peer_node_is_up(hdr))
			return false;
		tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
		return true;
	}

	if (state == SELF_LEAVING_PEER_DOWN)
		return false;

	/* Ignore duplicate packets */
	if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt))
		return true;

	/* Initiate or update failover mode if applicable */
	if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) {
		syncpt = oseqno + exp_pkts - 1;
		if (pl && !tipc_link_is_reset(pl)) {
			__tipc_node_link_down(n, &pb_id, xmitq, &maddr);
			trace_tipc_node_link_down(n, true,
						  "node link down <- failover!");
			tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl),
							tipc_link_inputq(l));
		}

		/* If parallel link was already down, and this happened before
		 * the tunnel link came up, node failover was never started.
		 * Ensure that a FAILOVER_MSG is sent to get peer out of
		 * NODE_FAILINGOVER state, also this node must accept
		 * TUNNEL_MSGs from peer.
		 */
		if (n->state != NODE_FAILINGOVER)
			tipc_node_link_failover(n, pl, l, xmitq);

		/* If pkts arrive out of order, use lowest calculated syncpt */
		if (less(syncpt, n->sync_point))
			n->sync_point = syncpt;
	}

	/* Open parallel link when tunnel link reaches synch point */
	if ((n->state == NODE_FAILINGOVER) && tipc_link_is_up(l)) {
		if (!more(rcv_nxt, n->sync_point))
			return true;
		tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT);
		if (pl)
			tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT);
		return true;
	}

	/* No synching needed if only one link */
	if (!pl || !tipc_link_is_up(pl))
		return true;

	/* Initiate synch mode if applicable */
	if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG) && (oseqno == 1)) {
		if (n->capabilities & TIPC_TUNNEL_ENHANCED)
			syncpt = msg_syncpt(hdr);
		else
			syncpt = msg_seqno(msg_inner_hdr(hdr)) + exp_pkts - 1;
		if (!tipc_link_is_up(l))
			__tipc_node_link_up(n, bearer_id, xmitq);
		if (n->state == SELF_UP_PEER_UP) {
			n->sync_point = syncpt;
			tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT);
			tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT);
		}
	}

	/* Open tunnel link when parallel link reaches synch point */
	if (n->state == NODE_SYNCHING) {
		if (tipc_link_is_synching(l)) {
			tnl = l;
		} else {
			tnl = pl;
			pl = l;
		}
		inputq_len = skb_queue_len(tipc_link_inputq(pl));
		dlv_nxt = tipc_link_rcv_nxt(pl) - inputq_len;
		if (more(dlv_nxt, n->sync_point)) {
			tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
			tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
			return true;
		}
		if (l == pl)
			return true;
		if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG))
			return true;
		if (usr == LINK_PROTOCOL)
			return true;
		return false;
	}
	return true;
}


int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
{
	struct tipc_node *node;
	struct tipc_sock_conn *conn;
	int err = 0;

	if (in_own_node(net, dnode))
		return 0;

	node = tipc_node_find(net, dnode);
	if (!node) {
		pr_warn("Connecting sock to node 0x%x failed\n", dnode);
		return -EHOSTUNREACH;
	}
	conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
	if (!conn) {
		err = -EHOSTUNREACH;
		goto exit;
	}
	conn->peer_node = dnode;
	conn->port = port;
	conn->peer_port = peer_port;

	tipc_node_write_lock(node);
	list_add_tail(&conn->list, &node->conn_sks);
	tipc_node_write_unlock(node);
exit:
	tipc_node_put(node);
	return err;
}


static struct tipc_link *node_active_link(struct tipc_node *n, int sel)
{
	int bearer_id = n->active_links[sel & 1];

	if (unlikely(bearer_id == INVALID_BEARER_ID))
		return NULL;

	return n->links[bearer_id].link;
}