mirror of
				https://github.com/torvalds/linux.git
				synced 2025-10-31 00:28:52 +02:00 
			
		
		
		
	 435bbcc3be
			
		
	
	
		435bbcc3be
		
	
	
	
	
		
			
			module_assert_mutex_or_preempt() is not needed in try_add_tainted_module(). The function checks for RCU-sched or the module_mutex to be acquired. The list_for_each_entry_rcu() below does the same check. Remove module_assert_mutex_or_preempt() from try_add_tainted_module(). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250108090457.512198-10-bigeasy@linutronix.de Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
		
			
				
	
	
		
			127 lines
		
	
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			127 lines
		
	
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-or-later
 | |
| /*
 | |
|  * Module taint unload tracking support
 | |
|  *
 | |
|  * Copyright (C) 2022 Aaron Tomlin
 | |
|  */
 | |
| 
 | |
| #include <linux/module.h>
 | |
| #include <linux/string.h>
 | |
| #include <linux/printk.h>
 | |
| #include <linux/slab.h>
 | |
| #include <linux/list.h>
 | |
| #include <linux/debugfs.h>
 | |
| #include <linux/rculist.h>
 | |
| #include "internal.h"
 | |
| 
 | |
| static LIST_HEAD(unloaded_tainted_modules);
 | |
| extern struct dentry *mod_debugfs_root;
 | |
| 
 | |
| int try_add_tainted_module(struct module *mod)
 | |
| {
 | |
| 	struct mod_unload_taint *mod_taint;
 | |
| 
 | |
| 	if (!mod->taints)
 | |
| 		goto out;
 | |
| 
 | |
| 	list_for_each_entry_rcu(mod_taint, &unloaded_tainted_modules, list,
 | |
| 				lockdep_is_held(&module_mutex)) {
 | |
| 		if (!strcmp(mod_taint->name, mod->name) &&
 | |
| 		    mod_taint->taints & mod->taints) {
 | |
| 			mod_taint->count++;
 | |
| 			goto out;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	mod_taint = kmalloc(sizeof(*mod_taint), GFP_KERNEL);
 | |
| 	if (unlikely(!mod_taint))
 | |
| 		return -ENOMEM;
 | |
| 	strscpy(mod_taint->name, mod->name, MODULE_NAME_LEN);
 | |
| 	mod_taint->taints = mod->taints;
 | |
| 	list_add_rcu(&mod_taint->list, &unloaded_tainted_modules);
 | |
| 	mod_taint->count = 1;
 | |
| out:
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| void print_unloaded_tainted_modules(void)
 | |
| {
 | |
| 	struct mod_unload_taint *mod_taint;
 | |
| 	char buf[MODULE_FLAGS_BUF_SIZE];
 | |
| 
 | |
| 	if (!list_empty(&unloaded_tainted_modules)) {
 | |
| 		printk(KERN_DEFAULT "Unloaded tainted modules:");
 | |
| 		list_for_each_entry_rcu(mod_taint, &unloaded_tainted_modules,
 | |
| 					list) {
 | |
| 			size_t l;
 | |
| 
 | |
| 			l = module_flags_taint(mod_taint->taints, buf);
 | |
| 			buf[l++] = '\0';
 | |
| 			pr_cont(" %s(%s):%llu", mod_taint->name, buf,
 | |
| 				mod_taint->count);
 | |
| 		}
 | |
| 	}
 | |
| }
 | |
| 
 | |
| #ifdef CONFIG_DEBUG_FS
 | |
| static void *unloaded_tainted_modules_seq_start(struct seq_file *m, loff_t *pos)
 | |
| 	__acquires(rcu)
 | |
| {
 | |
| 	rcu_read_lock();
 | |
| 	return seq_list_start_rcu(&unloaded_tainted_modules, *pos);
 | |
| }
 | |
| 
 | |
| static void *unloaded_tainted_modules_seq_next(struct seq_file *m, void *p, loff_t *pos)
 | |
| {
 | |
| 	return seq_list_next_rcu(p, &unloaded_tainted_modules, pos);
 | |
| }
 | |
| 
 | |
| static void unloaded_tainted_modules_seq_stop(struct seq_file *m, void *p)
 | |
| 	__releases(rcu)
 | |
| {
 | |
| 	rcu_read_unlock();
 | |
| }
 | |
| 
 | |
| static int unloaded_tainted_modules_seq_show(struct seq_file *m, void *p)
 | |
| {
 | |
| 	struct mod_unload_taint *mod_taint;
 | |
| 	char buf[MODULE_FLAGS_BUF_SIZE];
 | |
| 	size_t l;
 | |
| 
 | |
| 	mod_taint = list_entry(p, struct mod_unload_taint, list);
 | |
| 	l = module_flags_taint(mod_taint->taints, buf);
 | |
| 	buf[l++] = '\0';
 | |
| 
 | |
| 	seq_printf(m, "%s (%s) %llu", mod_taint->name, buf, mod_taint->count);
 | |
| 	seq_puts(m, "\n");
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static const struct seq_operations unloaded_tainted_modules_seq_ops = {
 | |
| 	.start = unloaded_tainted_modules_seq_start,
 | |
| 	.next  = unloaded_tainted_modules_seq_next,
 | |
| 	.stop  = unloaded_tainted_modules_seq_stop,
 | |
| 	.show  = unloaded_tainted_modules_seq_show,
 | |
| };
 | |
| 
 | |
| static int unloaded_tainted_modules_open(struct inode *inode, struct file *file)
 | |
| {
 | |
| 	return seq_open(file, &unloaded_tainted_modules_seq_ops);
 | |
| }
 | |
| 
 | |
| static const struct file_operations unloaded_tainted_modules_fops = {
 | |
| 	.open = unloaded_tainted_modules_open,
 | |
| 	.read = seq_read,
 | |
| 	.llseek = seq_lseek,
 | |
| 	.release = seq_release,
 | |
| };
 | |
| 
 | |
| static int __init unloaded_tainted_modules_init(void)
 | |
| {
 | |
| 	debugfs_create_file("unloaded_tainted", 0444, mod_debugfs_root, NULL,
 | |
| 			    &unloaded_tainted_modules_fops);
 | |
| 	return 0;
 | |
| }
 | |
| module_init(unloaded_tainted_modules_init);
 | |
| #endif /* CONFIG_DEBUG_FS */
 |