Q: Given the following code slice:
```
1 ice_debugfs_module_write(struct file *filp, const char __user *buf,
2 			 size_t count, loff_t *ppos)
3 {
4 	struct ice_pf *pf = file_inode(filp)->i_private;
5 	struct dentry *dentry = file_dentry(filp);
6 	struct device *dev = ice_pf_to_dev(pf);
7 	char user_val[16], *cmd_buf;
8 	int module, log_level, cnt;
9 
10 	/* don't allow partial writes or invalid input */
11 	if (*ppos != 0 || count > 8)
12 		return -EINVAL;
13 
14 	cmd_buf = memdup_user(buf, count);
15 	if (IS_ERR(cmd_buf))
16 		return PTR_ERR(cmd_buf);
17 
18 	module = ice_find_module_by_dentry(pf, dentry);
19 	if (module < 0) {
20 		dev_info(dev, "unknown module\n");
21 		return -EINVAL;
22 	}
23 
24 	cnt = sscanf(cmd_buf, "%s", user_val);
25 	if (cnt != 1)
26 		return -EINVAL;
27 
28 	log_level = sysfs_match_string(ice_fwlog_level_string, user_val);
29 	if (log_level < 0) {
30 		dev_info(dev, "unknown log level '%s'\n", user_val);
31 		return -EINVAL;
32 	}
33 
34 	if (module != ICE_AQC_FW_LOG_ID_MAX) {
35 		ice_pf_fwlog_update_module(pf, log_level, module);
36 	} else {
37 		/* the module 'all' is a shortcut so that we can set
38 		 * all of the modules to the same level quickly
39 		 */
40 		int i;
41 
42 		for (i = 0; i < ICE_AQC_FW_LOG_ID_MAX; i++)
43 			ice_pf_fwlog_update_module(pf, log_level, i);
44 	}
45 
46 	return count;
47 }
```
which has a vulnerability among CWE-787,CWE-125 and among lines:
```
14 	cmd_buf = memdup_user(buf, count);
24 	cnt = sscanf(cmd_buf, "%s", user_val);
```
Please generate five possible patches for the vulnerability.