1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Module taint unload tracking support
5 * Copyright (C) 2022 Aaron Tomlin
8 #include <linux/module.h>
9 #include <linux/string.h>
10 #include <linux/printk.h>
11 #include <linux/slab.h>
12 #include <linux/list.h>
13 #include <linux/debugfs.h>
14 #include <linux/rculist.h>
17 static LIST_HEAD(unloaded_tainted_modules);
19 int try_add_tainted_module(struct module *mod)
21 struct mod_unload_taint *mod_taint;
23 module_assert_mutex_or_preempt();
28 list_for_each_entry_rcu(mod_taint, &unloaded_tainted_modules, list,
29 lockdep_is_held(&module_mutex)) {
30 if (!strcmp(mod_taint->name, mod->name) &&
31 mod_taint->taints & mod->taints) {
37 mod_taint = kmalloc(sizeof(*mod_taint), GFP_KERNEL);
38 if (unlikely(!mod_taint))
40 strscpy(mod_taint->name, mod->name, MODULE_NAME_LEN);
41 mod_taint->taints = mod->taints;
42 list_add_rcu(&mod_taint->list, &unloaded_tainted_modules);
48 void print_unloaded_tainted_modules(void)
50 struct mod_unload_taint *mod_taint;
51 char buf[MODULE_FLAGS_BUF_SIZE];
53 if (!list_empty(&unloaded_tainted_modules)) {
54 printk(KERN_DEFAULT "Unloaded tainted modules:");
55 list_for_each_entry_rcu(mod_taint, &unloaded_tainted_modules,
59 l = module_flags_taint(mod_taint->taints, buf);
61 pr_cont(" %s(%s):%llu", mod_taint->name, buf,
67 #ifdef CONFIG_DEBUG_FS
68 static void *unloaded_tainted_modules_seq_start(struct seq_file *m, loff_t *pos)
72 return seq_list_start_rcu(&unloaded_tainted_modules, *pos);
75 static void *unloaded_tainted_modules_seq_next(struct seq_file *m, void *p, loff_t *pos)
77 return seq_list_next_rcu(p, &unloaded_tainted_modules, pos);
80 static void unloaded_tainted_modules_seq_stop(struct seq_file *m, void *p)
86 static int unloaded_tainted_modules_seq_show(struct seq_file *m, void *p)
88 struct mod_unload_taint *mod_taint;
89 char buf[MODULE_FLAGS_BUF_SIZE];
92 mod_taint = list_entry(p, struct mod_unload_taint, list);
93 l = module_flags_taint(mod_taint->taints, buf);
96 seq_printf(m, "%s (%s) %llu", mod_taint->name, buf, mod_taint->count);
102 static const struct seq_operations unloaded_tainted_modules_seq_ops = {
103 .start = unloaded_tainted_modules_seq_start,
104 .next = unloaded_tainted_modules_seq_next,
105 .stop = unloaded_tainted_modules_seq_stop,
106 .show = unloaded_tainted_modules_seq_show,
109 static int unloaded_tainted_modules_open(struct inode *inode, struct file *file)
111 return seq_open(file, &unloaded_tainted_modules_seq_ops);
114 static const struct file_operations unloaded_tainted_modules_fops = {
115 .open = unloaded_tainted_modules_open,
118 .release = seq_release,
121 static int __init unloaded_tainted_modules_init(void)
125 dir = debugfs_create_dir("modules", NULL);
126 debugfs_create_file("unloaded_tainted", 0444, dir, NULL,
127 &unloaded_tainted_modules_fops);
131 module_init(unloaded_tainted_modules_init);
132 #endif /* CONFIG_DEBUG_FS */