release 105

[elogind.git] / udev_rules.c

diff --git a/udev_rules.c b/udev_rules.c
index 8a2066d70931dee89a915d13b92d7360584c5e7f..d1c3f042c390ce5dd4c913a664159ffce350f1c2 100644 (file)
--- a/udev_rules.c
+++ b/udev_rules.c
@@ -364,6 +364,8 @@ void udev_rules_apply_format(struct udevice *udev, char *string, size_t maxsize)
                                                goto found;
                                        }
                                }
+                               head[0] = '$';
+                               err("unknown format variable '%s'", head);
                        } else if (head[0] == '%') {
                                /* substitute format char */
                                if (head[1] == '\0')
@@ -385,6 +387,8 @@ void udev_rules_apply_format(struct udevice *udev, char *string, size_t maxsize)
                                                goto found;
                                        }
                                }
+                               head[0] = '%';
+                               err("unknown format char '%c'", tail[0]);
                        }
                        head++;
                }
@@ -458,30 +462,42 @@ found:
                        }
                        break;
                case SUBST_ATTR:
-                       if (attr == NULL) {
-                               dbg("missing attribute");
-                               break;
-                       } else {
-                               struct sysfs_device *dev_parent;
-                               const char *value;
+                       if (attr == NULL)
+                               err("missing file parameter for attr");
+                       else {
+                               const char *value = NULL;
+                               size_t size;
+
+                               /* first try the current device, other matches may have selected */
+                               if (udev->dev_parent != NULL && udev->dev_parent != udev->dev)
+                                       value = sysfs_attr_get_value(udev->dev_parent->devpath, attr);
+
+                               /* look at all devices along the chain of parents */
+                               if (value == NULL) {
+                                       struct sysfs_device *dev_parent = udev->dev;
+
+                                       do {
+                                               dbg("looking at '%s'", dev_parent->devpath);
+                                               value = sysfs_attr_get_value(dev_parent->devpath, attr);
+                                               if (value != NULL) {
+                                                       strlcpy(temp2, value, sizeof(temp2));
+                                                       break;
+                                               }
+                                               dev_parent = sysfs_device_get_parent(dev_parent);
+                                       } while (dev_parent != NULL);
+                               }
 
-                               dev_parent = udev->dev;
-                               do {
-                                       dbg("looking at '%s'", dev_parent->devpath);
-                                       value = sysfs_attr_get_value(dev_parent->devpath, attr);
-                                       if (value != NULL) {
-                                               strlcpy(temp2, value, sizeof(temp2));
-                                               break;
-                                       }
-                                       dev_parent = sysfs_device_get_parent(dev_parent);
-                               } while (dev_parent != NULL);
+                               if (value == NULL)
+                                       break;
 
-                               /* strip trailing whitespace of sysfs value */
-                               i = strlen(temp2);
-                               while (i > 0 && isspace(temp2[i-1]))
-                                       temp2[--i] = '\0';
+                               /* strip trailing whitespace and replace untrusted characters of sysfs value */
+                               size = strlcpy(temp2, value, sizeof(temp2));
+                               if (size >= sizeof(temp2))
+                                       size = sizeof(temp2)-1;
+                               while (size > 0 && isspace(temp2[size-1]))
+                                       temp2[--size] = '\0';
                                count = replace_untrusted_chars(temp2);
-                               if (count)
+                               if (count > 0)
                                        info("%i untrusted character(s) replaced" , count);
                                strlcat(string, temp2, maxsize);
                                dbg("substitute sysfs value '%s'", temp2);
@@ -542,7 +558,7 @@ found:
                        break;
                }
                /* possibly truncate to format-char specified length */
-               if (len != -1) {
+               if (len >= 0 && len < (int)strlen(head)) {
                        head[len] = '\0';
                        dbg("truncate to %i chars, subtitution string becomes '%s'", len, head);
                }
@@ -693,7 +709,7 @@ static int match_rule(struct udevice *udev, struct udev_rule *rule)
                if (match_key("DRIVERS", rule, &rule->drivers, udev->dev_parent->driver))
                        goto try_parent;
 
-               /* check for matching sysfs attrubute pairs */
+               /* check for matching sysfs attribute pairs */
                for (i = 0; i < rule->attrs.count; i++) {
                        struct key_pair *pair = &rule->attrs.keys[i];
 
@@ -802,13 +818,19 @@ try_parent:
                struct key_pair *pair = &rule->env.keys[i];
 
                if (pair->key.operation == KEY_OP_ASSIGN) {
+                       char temp_value[NAME_SIZE];
                        const char *key_name = key_pair_name(rule, pair);
                        const char *value = key_val(rule, &pair->key);
-                       char *key_value = name_list_key_add(&udev->env_list, key_name, value);
+                       char *key_value;
+
+                       /* make sure we don't write to the same string we possibly read from */
+                       strlcpy(temp_value, value, sizeof(temp_value));
+                       udev_rules_apply_format(udev, temp_value, NAME_SIZE);
+
+                       key_value = name_list_key_add(&udev->env_list, key_name, temp_value);
                        if (key_value == NULL)
                                break;
 
-                       udev_rules_apply_format(udev, key_value, NAME_SIZE);
                        putenv(key_value);
                        dbg("export ENV '%s'", key_value);
                }