/* * Copyright (C) 2003,2004 Greg Kroah-Hartman * Copyright (C) 2003-2008 Kay Sievers * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include #include #include #include #include #include #include #include #include #include "udev.h" #include "udev-rules.h" void udev_rules_iter_init(struct udev_rules_iter *iter, struct udev_rules *rules) { dbg(rules->udev, "bufsize=%zi\n", rules->bufsize); iter->rules = rules; iter->current = 0; } struct udev_rule *udev_rules_iter_next(struct udev_rules_iter *iter) { struct udev_rules *rules; struct udev_rule *rule; rules = iter->rules; if (!rules) return NULL; dbg(rules->udev, "current=%zi\n", iter->current); if (iter->current >= rules->bufsize) { dbg(rules->udev, "no more rules\n"); return NULL; } /* get next rule */ rule = (struct udev_rule *) (rules->buf + iter->current); iter->current += sizeof(struct udev_rule) + rule->bufsize; return rule; } struct udev_rule *udev_rules_iter_goto(struct udev_rules_iter *iter, size_t rule_off) { struct udev_rules *rules = iter->rules; struct udev_rule *rule; dbg(rules->udev, "current=%zi\n", iter->current); iter->current = rule_off; rule = (struct udev_rule *) (rules->buf + iter->current); return rule; } static size_t find_label(const struct udev_rules_iter *iter, const char *label) { struct udev_rule *rule; struct udev_rules *rules = iter->rules; size_t current = iter->current; next: dbg(rules->udev, "current=%zi\n", current); if (current >= rules->bufsize) { dbg(rules->udev, "LABEL='%s' not found\n", label); return 0; } rule = (struct udev_rule *) (rules->buf + current); if (strcmp(&rule->buf[rule->label.val_off], label) != 0) { dbg(rules->udev, "moving forward, looking for label '%s'\n", label); current += sizeof(struct udev_rule) + rule->bufsize; goto next; } dbg(rules->udev, "found label '%s'\n", label); return current; } static int get_key(struct udev_rules *rules, char **line, char **key, enum key_operation *operation, char **value) { char *linepos; char *temp; linepos = *line; if (linepos == NULL && linepos[0] == '\0') return -1; /* skip whitespace */ while (isspace(linepos[0]) || linepos[0] == ',') linepos++; /* get the key */ if (linepos[0] == '\0') return -1; *key = linepos; while (1) { linepos++; if (linepos[0] == '\0') return -1; if (isspace(linepos[0])) break; if (linepos[0] == '=') break; if ((linepos[0] == '+') || (linepos[0] == '!') || (linepos[0] == ':')) if (linepos[1] == '=') break; } /* remember end of key */ temp = linepos; /* skip whitespace after key */ while (isspace(linepos[0])) linepos++; if (linepos[0] == '\0') return -1; /* get operation type */ if (linepos[0] == '=' && linepos[1] == '=') { *operation = KEY_OP_MATCH; linepos += 2; dbg(rules->udev, "match:\n"); } else if (linepos[0] == '!' && linepos[1] == '=') { *operation = KEY_OP_NOMATCH; linepos += 2; dbg(rules->udev, "nomatch:\n"); } else if (linepos[0] == '+' && linepos[1] == '=') { *operation = KEY_OP_ADD; linepos += 2; dbg(rules->udev, "add:\n"); } else if (linepos[0] == '=') { *operation = KEY_OP_ASSIGN; linepos++; dbg(rules->udev, "assign:\n"); } else if (linepos[0] == ':' && linepos[1] == '=') { *operation = KEY_OP_ASSIGN_FINAL; linepos += 2; dbg(rules->udev, "assign_final:\n"); } else return -1; /* terminate key */ temp[0] = '\0'; /* skip whitespace after operator */ while (isspace(linepos[0])) linepos++; if (linepos[0] == '\0') return -1; /* get the value*/ if (linepos[0] == '"') linepos++; else return -1; *value = linepos; temp = strchr(linepos, '"'); if (!temp) return -1; temp[0] = '\0'; temp++; dbg(rules->udev, "'%s'-'%s'\n", *key, *value); /* move line to next key */ *line = temp; return 0; } /* extract possible KEY{attr} */ static char *get_key_attribute(struct udev_rules *rules, char *str) { char *pos; char *attr; attr = strchr(str, '{'); if (attr != NULL) { attr++; pos = strchr(attr, '}'); if (pos == NULL) { err(rules->udev, "missing closing brace for format\n"); return NULL; } pos[0] = '\0'; dbg(rules->udev, "attribute='%s'\n", attr); return attr; } return NULL; } static int add_rule_key(struct udev_rule *rule, struct key *key, enum key_operation operation, const char *value) { size_t val_len = strnlen(value, UTIL_PATH_SIZE); key->operation = operation; key->val_off = rule->bufsize; util_strlcpy(rule->buf + rule->bufsize, value, val_len+1); rule->bufsize += val_len+1; return 0; } static int add_rule_key_pair(struct udev_rules *rules, struct udev_rule *rule, struct key_pairs *pairs, enum key_operation operation, const char *key, const char *value) { size_t key_len = strnlen(key, UTIL_PATH_SIZE); if (pairs->count >= PAIRS_MAX) { err(rules->udev, "skip, too many keys of the same type in a single rule\n"); return -1; } add_rule_key(rule, &pairs->keys[pairs->count].key, operation, value); /* add the key-name of the pair */ pairs->keys[pairs->count].key_name_off = rule->bufsize; util_strlcpy(rule->buf + rule->bufsize, key, key_len+1); rule->bufsize += key_len+1; pairs->count++; return 0; } static int add_to_rules(struct udev_rules *rules, char *line, const char *filename, unsigned int lineno) { char buf[sizeof(struct udev_rule) + UTIL_LINE_SIZE]; struct udev_rule *rule; size_t rule_size; int valid; char *linepos; char *attr; size_t padding; int physdev = 0; int retval; memset(buf, 0x00, sizeof(buf)); rule = (struct udev_rule *) buf; rule->event_timeout = -1; linepos = line; valid = 0; /* get all the keys */ while (1) { char *key; char *value; enum key_operation operation = KEY_OP_UNSET; retval = get_key(rules, &linepos, &key, &operation, &value); if (retval) break; if (strcasecmp(key, "ACTION") == 0) { if (operation != KEY_OP_MATCH && operation != KEY_OP_NOMATCH) { err(rules->udev, "invalid ACTION operation\n"); goto invalid; } add_rule_key(rule, &rule->action, operation, value); valid = 1; continue; } if (strcasecmp(key, "DEVPATH") == 0) { if (operation != KEY_OP_MATCH && operation != KEY_OP_NOMATCH) { err(rules->udev, "invalid DEVPATH operation\n"); goto invalid; } add_rule_key(rule, &rule->devpath, operation, value); valid = 1; continue; } if (strcasecmp(key, "KERNEL") == 0) { if (operation != KEY_OP_MATCH && operation != KEY_OP_NOMATCH) { err(rules->udev, "invalid KERNEL operation\n"); goto invalid; } add_rule_key(rule, &rule->kernel, operation, value); valid = 1; continue; } if (strcasecmp(key, "SUBSYSTEM") == 0) { if (operation != KEY_OP_MATCH && operation != KEY_OP_NOMATCH) { err(rules->udev, "invalid SUBSYSTEM operation\n"); goto invalid; } /* bus, class, subsystem events should all be the same */ if (strcmp(value, "subsystem") == 0 || strcmp(value, "bus") == 0 || strcmp(value, "class") == 0) { if (strcmp(value, "bus") == 0 || strcmp(value, "class") == 0) err(rules->udev, "'%s' must be specified as 'subsystem' \n" "please fix it in %s:%u", value, filename, lineno); add_rule_key(rule, &rule->subsystem, operation, "subsystem|class|bus"); } else add_rule_key(rule, &rule->subsystem, operation, value); valid = 1; continue; } if (strcasecmp(key, "DRIVER") == 0) { if (operation != KEY_OP_MATCH && operation != KEY_OP_NOMATCH) { err(rules->udev, "invalid DRIVER operation\n"); goto invalid; } add_rule_key(rule, &rule->driver, operation, value); valid = 1; continue; } if (strncasecmp(key, "ATTR{", sizeof("ATTR{")-1) == 0) { attr = get_key_attribute(rules, key + sizeof("ATTR")-1); if (attr == NULL) { err(rules->udev, "error parsing ATTR attribute\n"); goto invalid; } if (add_rule_key_pair(rules, rule, &rule->attr, operation, attr, value) != 0) goto invalid; valid = 1; continue; } if (strcasecmp(key, "KERNELS") == 0 || strcasecmp(key, "ID") == 0) { if (operation != KEY_OP_MATCH && operation != KEY_OP_NOMATCH) { err(rules->udev, "invalid KERNELS operation\n"); goto invalid; } add_rule_key(rule, &rule->kernels, operation, value); valid = 1; continue; } if (strcasecmp(key, "SUBSYSTEMS") == 0 || strcasecmp(key, "BUS") == 0) { if (operation != KEY_OP_MATCH && operation != KEY_OP_NOMATCH) { err(rules->udev, "invalid SUBSYSTEMS operation\n"); goto invalid; } add_rule_key(rule, &rule->subsystems, operation, value); valid = 1; continue; } if (strcasecmp(key, "DRIVERS") == 0) { if (operation != KEY_OP_MATCH && operation != KEY_OP_NOMATCH) { err(rules->udev, "invalid DRIVERS operation\n"); goto invalid; } add_rule_key(rule, &rule->drivers, operation, value); valid = 1; continue; } if (strncasecmp(key, "ATTRS{", sizeof("ATTRS{")-1) == 0 || strncasecmp(key, "SYSFS{", sizeof("SYSFS{")-1) == 0) { if (operation != KEY_OP_MATCH && operation != KEY_OP_NOMATCH) { err(rules->udev, "invalid ATTRS operation\n"); goto invalid; } attr = get_key_attribute(rules, key + sizeof("ATTRS")-1); if (attr == NULL) { err(rules->udev, "error parsing ATTRS attribute\n"); goto invalid; } if (strncmp(attr, "device/", 7) == 0) err(rules->udev, "the 'device' link is deprecated and will be removed from a future kernel, \n" "please fix it in %s:%u", filename, lineno); else if (strstr(attr, "../") != NULL) err(rules->udev, "do not reference parent sysfs directories directly, that may break with a future kernel, \n" "please fix it in %s:%u", filename, lineno); if (add_rule_key_pair(rules, rule, &rule->attrs, operation, attr, value) != 0) goto invalid; valid = 1; continue; } if (strncasecmp(key, "ENV{", sizeof("ENV{")-1) == 0) { attr = get_key_attribute(rules, key + sizeof("ENV")-1); if (attr == NULL) { err(rules->udev, "error parsing ENV attribute\n"); goto invalid; } if (strncmp(attr, "PHYSDEV", 7) == 0) physdev = 1; if (add_rule_key_pair(rules, rule, &rule->env, operation, attr, value) != 0) goto invalid; valid = 1; continue; } if (strcasecmp(key, "PROGRAM") == 0) { add_rule_key(rule, &rule->program, operation, value); valid = 1; continue; } if (strcasecmp(key, "RESULT") == 0) { if (operation != KEY_OP_MATCH && operation != KEY_OP_NOMATCH) { err(rules->udev, "invalid RESULT operation\n"); goto invalid; } add_rule_key(rule, &rule->result, operation, value); valid = 1; continue; } if (strncasecmp(key, "IMPORT", sizeof("IMPORT")-1) == 0) { attr = get_key_attribute(rules, key + sizeof("IMPORT")-1); if (attr != NULL && strstr(attr, "program")) { dbg(rules->udev, "IMPORT will be executed\n"); rule->import_type = IMPORT_PROGRAM; } else if (attr != NULL && strstr(attr, "file")) { dbg(rules->udev, "IMPORT will be included as file\n"); rule->import_type = IMPORT_FILE; } else if (attr != NULL && strstr(attr, "parent")) { dbg(rules->udev, "IMPORT will include the parent values\n"); rule->import_type = IMPORT_PARENT; } else { /* figure it out if it is executable */ char file[UTIL_PATH_SIZE]; char *pos; struct stat statbuf; util_strlcpy(file, value, sizeof(file)); pos = strchr(file, ' '); if (pos) pos[0] = '\0'; /* allow programs in /lib/udev called without the path */ if (strchr(file, '/') == NULL) { util_strlcpy(file, UDEV_PREFIX "/lib/udev/", sizeof(file)); util_strlcat(file, value, sizeof(file)); pos = strchr(file, ' '); if (pos) pos[0] = '\0'; } dbg(rules->udev, "IMPORT auto mode for '%s'\n", file); if (!lstat(file, &statbuf) && (statbuf.st_mode & S_IXUSR)) { dbg(rules->udev, "IMPORT is executable, will be executed (autotype)\n"); rule->import_type = IMPORT_PROGRAM; } else { dbg(rules->udev, "IMPORT is not executable, will be included as file (autotype)\n"); rule->import_type = IMPORT_FILE; } } add_rule_key(rule, &rule->import, operation, value); valid = 1; continue; } if (strncasecmp(key, "TEST", sizeof("TEST")-1) == 0) { if (operation != KEY_OP_MATCH && operation != KEY_OP_NOMATCH) { err(rules->udev, "invalid TEST operation\n"); goto invalid; } attr = get_key_attribute(rules, key + sizeof("TEST")-1); if (attr != NULL) rule->test_mode_mask = strtol(attr, NULL, 8); add_rule_key(rule, &rule->test, operation, value); valid = 1; continue; } if (strncasecmp(key, "RUN", sizeof("RUN")-1) == 0) { attr = get_key_attribute(rules, key + sizeof("RUN")-1); if (attr != NULL) { if (strstr(attr, "ignore_error")) rule->run_ignore_error = 1; } add_rule_key(rule, &rule->run, operation, value); valid = 1; continue; } if (strcasecmp(key, "WAIT_FOR") == 0 || strcasecmp(key, "WAIT_FOR_SYSFS") == 0) { add_rule_key(rule, &rule->wait_for, operation, value); valid = 1; continue; } if (strcasecmp(key, "LABEL") == 0) { add_rule_key(rule, &rule->label, operation, value); valid = 1; continue; } if (strcasecmp(key, "GOTO") == 0) { add_rule_key(rule, &rule->goto_label, operation, value); valid = 1; continue; } if (strncasecmp(key, "NAME", sizeof("NAME")-1) == 0) { attr = get_key_attribute(rules, key + sizeof("NAME")-1); if (attr != NULL) { if (strstr(attr, "all_partitions") != NULL) { dbg(rules->udev, "creation of partition nodes requested\n"); rule->partitions = DEFAULT_PARTITIONS_COUNT; } if (strstr(attr, "ignore_remove") != NULL) { dbg(rules->udev, "remove event should be ignored\n"); rule->ignore_remove = 1; } } if (value[0] == '\0') dbg(rules->udev, "name empty, node creation supressed\n"); add_rule_key(rule, &rule->name, operation, value); continue; } if (strcasecmp(key, "SYMLINK") == 0) { if (operation == KEY_OP_MATCH || operation == KEY_OP_NOMATCH) add_rule_key(rule, &rule->symlink_match, operation, value); else add_rule_key(rule, &rule->symlink, operation, value); valid = 1; continue; } if (strcasecmp(key, "OWNER") == 0) { valid = 1; if (rules->resolve_names && (!strchr(value, '$') && !strchr(value, '%'))) { char *endptr; strtoul(value, &endptr, 10); if (endptr[0] != '\0') { char owner[32]; uid_t uid = lookup_user(rules->udev, value); dbg(rules->udev, "replacing username='%s' by id=%i\n", value, uid); sprintf(owner, "%u", (unsigned int) uid); add_rule_key(rule, &rule->owner, operation, owner); continue; } } add_rule_key(rule, &rule->owner, operation, value); continue; } if (strcasecmp(key, "GROUP") == 0) { valid = 1; if (rules->resolve_names && (!strchr(value, '$') && !strchr(value, '%'))) { char *endptr; strtoul(value, &endptr, 10); if (endptr[0] != '\0') { char group[32]; gid_t gid = lookup_group(rules->udev, value); dbg(rules->udev, "replacing groupname='%s' by id=%i\n", value, gid); sprintf(group, "%u", (unsigned int) gid); add_rule_key(rule, &rule->group, operation, group); continue; } } add_rule_key(rule, &rule->group, operation, value); continue; } if (strcasecmp(key, "MODE") == 0) { add_rule_key(rule, &rule->mode, operation, value); valid = 1; continue; } if (strcasecmp(key, "OPTIONS") == 0) { const char *pos; if (strstr(value, "last_rule") != NULL) { dbg(rules->udev, "last rule to be applied\n"); rule->last_rule = 1; } if (strstr(value, "ignore_device") != NULL) { dbg(rules->udev, "device should be ignored\n"); rule->ignore_device = 1; } if (strstr(value, "ignore_remove") != NULL) { dbg(rules->udev, "remove event should be ignored\n"); rule->ignore_remove = 1; } pos = strstr(value, "link_priority="); if (pos != NULL) { rule->link_priority = atoi(&pos[strlen("link_priority=")]); dbg(rules->udev, "link priority=%i\n", rule->link_priority); } pos = strstr(value, "event_timeout="); if (pos != NULL) { rule->event_timeout = atoi(&pos[strlen("event_timeout=")]); dbg(rules->udev, "event timout=%i\n", rule->event_timeout); } pos = strstr(value, "string_escape="); if (pos != NULL) { pos = &pos[strlen("string_escape=")]; if (strncmp(pos, "none", strlen("none")) == 0) rule->string_escape = ESCAPE_NONE; else if (strncmp(pos, "replace", strlen("replace")) == 0) rule->string_escape = ESCAPE_REPLACE; } if (strstr(value, "all_partitions") != NULL) { dbg(rules->udev, "creation of partition nodes requested\n"); rule->partitions = DEFAULT_PARTITIONS_COUNT; } valid = 1; continue; } err(rules->udev, "unknown key '%s' in %s:%u\n", key, filename, lineno); } if (physdev && rule->wait_for.operation == KEY_OP_UNSET) err(rules->udev, "PHYSDEV* values are deprecated and will be removed from a future kernel, \n" "please fix it in %s:%u", filename, lineno); /* skip line if not any valid key was found */ if (!valid) goto invalid; /* grow buffer and add rule */ rule_size = sizeof(struct udev_rule) + rule->bufsize; padding = (sizeof(size_t) - rule_size % sizeof(size_t)) % sizeof(size_t); dbg(rules->udev, "add %zi padding bytes\n", padding); rule_size += padding; rule->bufsize += padding; rules->buf = realloc(rules->buf, rules->bufsize + rule_size); if (!rules->buf) { err(rules->udev, "realloc failed\n"); goto exit; } dbg(rules->udev, "adding rule to offset %zi\n", rules->bufsize); memcpy(rules->buf + rules->bufsize, rule, rule_size); rules->bufsize += rule_size; exit: return 0; invalid: err(rules->udev, "invalid rule '%s:%u'\n", filename, lineno); return -1; } static int parse_file(struct udev_rules *rules, const char *filename) { FILE *f; char line[UTIL_LINE_SIZE]; size_t start; struct udev_rule *rule; struct udev_rules_iter iter; start = rules->bufsize; info(rules->udev, "reading '%s' as rules file\n", filename); f = fopen(filename, "r"); if (f == NULL) return -1; while(fgets(line, sizeof(line), f) != NULL) { int line_nr = 0; char *key; size_t len; /* skip whitespace */ line_nr++; key = line; while (isspace(key[0])) key++; /* comment */ if (key[0] == '#') continue; len = strlen(line); if (len < 3) continue; /* continue reading if backslash+newline is found */ while (line[len-2] == '\\') { if (fgets(&line[len-2], (sizeof(line)-len)+2, f) == NULL) break; line_nr++; len = strlen(line); } if (len+1 >= sizeof(line)) { err(rules->udev, "line too long '%s':%u, ignored\n", filename, line_nr); continue; } add_to_rules(rules, key, filename, line_nr); } fclose(f); /* compute all goto targets within this file */ udev_rules_iter_init(&iter, rules); udev_rules_iter_goto(&iter, start); while((rule = udev_rules_iter_next(&iter))) { if (rule->goto_label.operation != KEY_OP_UNSET) { char *goto_label = &rule->buf[rule->goto_label.val_off]; dbg(rules->udev, "resolving goto label '%s'\n", goto_label); rule->goto_rule_off = find_label(&iter, goto_label); if (rule->goto_rule_off == 0) { err(rules->udev, "ignore goto to nonexistent label '%s' in '%s'\n", goto_label, filename); rule->goto_rule_off = iter.current; } } } return 0; } static int add_matching_files(struct udev *udev, struct udev_list_node *file_list, const char *dirname, const char *suffix) { struct dirent *ent; DIR *dir; char filename[UTIL_PATH_SIZE]; dbg(udev, "open directory '%s'\n", dirname); dir = opendir(dirname); if (dir == NULL) { err(udev, "unable to open '%s': %m\n", dirname); return -1; } while (1) { ent = readdir(dir); if (ent == NULL || ent->d_name[0] == '\0') break; if ((ent->d_name[0] == '.') || (ent->d_name[0] == '#')) continue; /* look for file matching with specified suffix */ if (suffix != NULL) { const char *ext; ext = strrchr(ent->d_name, '.'); if (ext == NULL) continue; if (strcmp(ext, suffix) != 0) continue; } dbg(udev, "put file '%s/%s' into list\n", dirname, ent->d_name); snprintf(filename, sizeof(filename), "%s/%s", dirname, ent->d_name); filename[sizeof(filename)-1] = '\0'; udev_list_entry_add(udev, file_list, filename, NULL, 1, 1); } closedir(dir); return 0; } int udev_rules_init(struct udev *udev, struct udev_rules *rules, int resolve_names) { struct stat statbuf; char filename[PATH_MAX]; struct udev_list_node file_list; struct udev_list_entry *file_loop, *file_tmp; int retval = 0; memset(rules, 0x00, sizeof(struct udev_rules)); rules->udev = udev; rules->resolve_names = resolve_names; udev_list_init(&file_list); if (udev_get_rules_path(udev) != NULL) { /* custom rules location for testing */ add_matching_files(udev, &file_list, udev_get_rules_path(udev), ".rules"); } else { struct udev_list_node sort_list; struct udev_list_entry *sort_loop, *sort_tmp; /* read user/custom rules */ add_matching_files(udev, &file_list, SYSCONFDIR "/udev/rules.d", ".rules"); /* read dynamic/temporary rules */ util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename)); util_strlcat(filename, "/.udev/rules.d", sizeof(filename)); if (stat(filename, &statbuf) != 0) { create_path(udev, filename); udev_selinux_setfscreatecon(udev, filename, S_IFDIR|0755); mkdir(filename, 0755); udev_selinux_resetfscreatecon(udev); } udev_list_init(&sort_list); add_matching_files(udev, &sort_list, filename, ".rules"); /* read default rules */ add_matching_files(udev, &sort_list, UDEV_PREFIX "/lib/udev/rules.d", ".rules"); /* sort all rules files by basename into list of files */ udev_list_entry_foreach_safe(sort_loop, sort_tmp, udev_list_get_entry(&sort_list)) { const char *sort_name = udev_list_entry_get_name(sort_loop); const char *sort_base = strrchr(sort_name, '/'); if (sort_base == NULL) continue; udev_list_entry_foreach_safe(file_loop, file_tmp, udev_list_get_entry(&file_list)) { const char *file_name = udev_list_entry_get_name(file_loop); const char *file_base = strrchr(file_name, '/'); if (file_base == NULL) continue; if (strcmp(file_base, sort_base) == 0) { info(udev, "rule file basename '%s' already added, ignoring '%s'\n", file_name, sort_name); udev_list_entry_remove(sort_loop); sort_loop = NULL; break; } if (strcmp(file_base, sort_base) > 0) break; } if (sort_loop != NULL) udev_list_entry_move_before(sort_loop, file_loop); } } /* parse list of files */ udev_list_entry_foreach_safe(file_loop, file_tmp, udev_list_get_entry(&file_list)) { const char *file_name = udev_list_entry_get_name(file_loop); if (stat(file_name, &statbuf) == 0 && statbuf.st_size > 0) parse_file(rules, file_name); else info(udev, "can not read '%s'\n", file_name); udev_list_entry_remove(file_loop); } return retval; } void udev_rules_cleanup(struct udev_rules *rules) { if (rules->buf) { free(rules->buf); rules->buf = NULL; } }