Be more careful when checking for empty files

[elogind.git] / src / udev / udev-rules.c

diff --git a/src/udev/udev-rules.c b/src/udev/udev-rules.c
index 47bde618d66484a865105d998e0a22f1f08d703a..9864016d1447c1ab041ead6ed0d515d22f73d5a8 100644 (file)
--- a/src/udev/udev-rules.c
+++ b/src/udev/udev-rules.c
@@ -1142,7 +1142,7 @@ static int add_rule(struct udev_rules *rules, char *line,
                 }
 
                 if (startswith(key, "ATTR{")) {
-                        attr = get_key_attribute(rules->udev, key + sizeof("ATTR")-1);
+                        attr = get_key_attribute(rules->udev, key + strlen("ATTR"));
                         if (attr == NULL) {
                                 log_error("error parsing ATTR attribute");
                                 goto invalid;
@@ -1156,7 +1156,7 @@ static int add_rule(struct udev_rules *rules, char *line,
                 }
 
                 if (startswith(key, "SECLABEL{")) {
-                        attr = get_key_attribute(rules->udev, key + sizeof("SECLABEL")-1);
+                        attr = get_key_attribute(rules->udev, key + strlen("SECLABEL"));
                         if (!attr) {
                                 log_error("error parsing SECLABEL attribute");
                                 goto invalid;
@@ -1198,7 +1198,7 @@ static int add_rule(struct udev_rules *rules, char *line,
                                 log_error("invalid ATTRS operation");
                                 goto invalid;
                         }
-                        attr = get_key_attribute(rules->udev, key + sizeof("ATTRS")-1);
+                        attr = get_key_attribute(rules->udev, key + strlen("ATTRS"));
                         if (attr == NULL) {
                                 log_error("error parsing ATTRS attribute");
                                 goto invalid;
@@ -1223,7 +1223,7 @@ static int add_rule(struct udev_rules *rules, char *line,
                 }
 
                 if (startswith(key, "ENV{")) {
-                        attr = get_key_attribute(rules->udev, key + sizeof("ENV")-1);
+                        attr = get_key_attribute(rules->udev, key + strlen("ENV"));
                         if (attr == NULL) {
                                 log_error("error parsing ENV attribute");
                                 goto invalid;
@@ -1282,7 +1282,7 @@ static int add_rule(struct udev_rules *rules, char *line,
                 }
 
                 if (startswith(key, "IMPORT")) {
-                        attr = get_key_attribute(rules->udev, key + sizeof("IMPORT")-1);
+                        attr = get_key_attribute(rules->udev, key + strlen("IMPORT"));
                         if (attr == NULL) {
                                 log_error("IMPORT{} type missing, ignoring IMPORT %s:%u", filename, lineno);
                                 continue;
@@ -1328,7 +1328,7 @@ static int add_rule(struct udev_rules *rules, char *line,
                                 log_error("invalid TEST operation");
                                 goto invalid;
                         }
-                        attr = get_key_attribute(rules->udev, key + sizeof("TEST")-1);
+                        attr = get_key_attribute(rules->udev, key + strlen("TEST"));
                         if (attr != NULL) {
                                 mode = strtol(attr, NULL, 8);
                                 rule_add_key(&rule_tmp, TK_M_TEST, op, value, &mode);
@@ -1339,7 +1339,7 @@ static int add_rule(struct udev_rules *rules, char *line,
                 }
 
                 if (startswith(key, "RUN")) {
-                        attr = get_key_attribute(rules->udev, key + sizeof("RUN")-1);
+                        attr = get_key_attribute(rules->udev, key + strlen("RUN"));
                         if (attr == NULL)
                                 attr = "program";
 
@@ -1533,15 +1533,19 @@ static int parse_file(struct udev_rules *rules, const char *filename)
         int line_nr = 0;
         unsigned int i;
 
-        if (null_or_empty_path(filename)) {
-                log_debug("skip empty file: %s", filename);
-                return 0;
+        f = fopen(filename, "re");
+        if (!f) {
+                if (errno == ENOENT)
+                        return 0;
+                else
+                        return -errno;
         }
-        log_debug("read rules file: %s", filename);
 
-        f = fopen(filename, "re");
-        if (f == NULL)
-                return -1;
+        if (null_or_empty_fd(fileno(f))) {
+                log_debug("Skipping empty file: %s", filename);
+                return 0;
+        } else
+                log_debug("Reading rules file: %s", filename);
 
         first_token = rules->token_cur;
         filename_off = rules_add_string(rules, filename);
@@ -2027,7 +2031,7 @@ int udev_rules_apply_to_event(struct udev_rules *rules, struct udev_event *event
                 case TK_M_PROGRAM: {
                         char program[UTIL_PATH_SIZE];
                         char **envp;
-                        char result[UTIL_PATH_SIZE];
+                        char result[UTIL_LINE_SIZE];
 
                         free(event->program_result);
                         event->program_result = NULL;
@@ -2555,10 +2559,15 @@ int udev_rules_apply_static_dev_perms(struct udev_rules *rules)
                         struct stat stats;
 
                         /* we assure, that the permissions tokens are sorted before the static token */
+
                         if (mode == 0 && uid == 0 && gid == 0 && tags == NULL)
                                 goto next;
 
                         strscpyl(device_node, sizeof(device_node), "/dev/", rules_str(rules, cur->key.value_off), NULL);
+                        if (stat(device_node, &stats) != 0)
+                                break;
+                        if (!S_ISBLK(stats.st_mode) && !S_ISCHR(stats.st_mode))
+                                break;
 
                         /* export the tags to a directory as symlinks, allowing otherwise dead nodes to be tagged */
                         if (tags) {
@@ -2588,11 +2597,6 @@ int udev_rules_apply_static_dev_perms(struct udev_rules *rules)
                         if (mode == 0 && uid == 0 && gid == 0)
                                 break;
 
-                        if (stat(device_node, &stats) != 0)
-                                break;
-                        if (!S_ISBLK(stats.st_mode) && !S_ISCHR(stats.st_mode))
-                                break;
-
                         if (mode == 0) {
                                 if (gid > 0)
                                         mode = 0660;