Q: Given the following code slice:
```
1 int pinctrl_dt_to_map(struct pinctrl *p, struct pinctrl_dev *pctldev)
2 {
3 	struct device_node *np = p->dev->of_node;
4 	int state, ret;
5 	char *propname;
6 	struct property *prop;
7 	const char *statename;
8 	const __be32 *list;
9 	int size, config;
10 	phandle phandle;
11 	struct device_node *np_config;
12 
13 	/* CONFIG_OF enabled, p->dev not instantiated from DT */
14 	if (!np) {
15 		if (of_have_populated_dt())
16 			dev_dbg(p->dev,
17 				"no of_node; not parsing pinctrl DT\n");
18 		return 0;
19 	}
20 
21 	/* We may store pointers to property names within the node */
22 	of_node_get(np);
23 
24 	/* For each defined state ID */
25 	for (state = 0; ; state++) {
26 		/* Retrieve the pinctrl-* property */
27 		propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state);
28 		if (!propname)
29 			return -ENOMEM;
30 		prop = of_find_property(np, propname, &size);
31 		kfree(propname);
32 		if (!prop) {
33 			if (state == 0) {
34 				of_node_put(np);
35 				return -ENODEV;
36 			}
37 			break;
38 		}
39 		list = prop->value;
40 		size /= sizeof(*list);
41 
42 		/* Determine whether pinctrl-names property names the state */
43 		ret = of_property_read_string_index(np, "pinctrl-names",
44 						    state, &statename);
45 		/*
46 		 * If not, statename is just the integer state ID. But rather
47 		 * than dynamically allocate it and have to free it later,
48 		 * just point part way into the property name for the string.
49 		 */
50 		if (ret < 0)
51 			statename = prop->name + strlen("pinctrl-");
52 
53 		/* For every referenced pin configuration node in it */
54 		for (config = 0; config < size; config++) {
55 			phandle = be32_to_cpup(list++);
56 
57 			/* Look up the pin configuration node */
58 			np_config = of_find_node_by_phandle(phandle);
59 			if (!np_config) {
60 				dev_err(p->dev,
61 					"prop %s index %i invalid phandle\n",
62 					prop->name, config);
63 				ret = -EINVAL;
64 				goto err;
65 			}
66 
67 			/* Parse the node */
68 			ret = dt_to_map_one_config(p, pctldev, statename,
69 						   np_config);
70 			of_node_put(np_config);
71 			if (ret < 0)
72 				goto err;
73 		}
74 
75 		/* No entries in DT? Generate a dummy state table entry */
76 		if (!size) {
77 			ret = dt_remember_dummy_state(p, statename);
78 			if (ret < 0)
79 				goto err;
80 		}
81 	}
82 
83 	return 0;
84 
85 err:
86 	pinctrl_dt_free_maps(p);
87 	return ret;
88 }
```
which has a vulnerability among CWE-476 and among lines:
```
28 		if (!propname)
```
Please generate five possible patches for the vulnerability.