mirror of
				https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
				synced 2025-10-31 22:26:12 +00:00 
			
		
		
		
	 5170836679
			
		
	
	
		5170836679
		
	
	
	
	
		
			
			free_uid() and free_user_ns() are corecursive when CONFIG_USER_SCHED=n, but free_user_ns() is called from free_uid() by way of uid_hash_remove(), which requires uidhash_lock to be held. free_user_ns() then calls free_uid() to complete the destruction. Fix this by deferring the destruction of the user_namespace. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			58 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			58 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef _LINUX_USER_NAMESPACE_H
 | |
| #define _LINUX_USER_NAMESPACE_H
 | |
| 
 | |
| #include <linux/kref.h>
 | |
| #include <linux/nsproxy.h>
 | |
| #include <linux/sched.h>
 | |
| #include <linux/err.h>
 | |
| 
 | |
| #define UIDHASH_BITS	(CONFIG_BASE_SMALL ? 3 : 8)
 | |
| #define UIDHASH_SZ	(1 << UIDHASH_BITS)
 | |
| 
 | |
| struct user_namespace {
 | |
| 	struct kref		kref;
 | |
| 	struct hlist_head	uidhash_table[UIDHASH_SZ];
 | |
| 	struct user_struct	*creator;
 | |
| 	struct work_struct	destroyer;
 | |
| };
 | |
| 
 | |
| extern struct user_namespace init_user_ns;
 | |
| 
 | |
| #ifdef CONFIG_USER_NS
 | |
| 
 | |
| static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
 | |
| {
 | |
| 	if (ns)
 | |
| 		kref_get(&ns->kref);
 | |
| 	return ns;
 | |
| }
 | |
| 
 | |
| extern int create_user_ns(struct cred *new);
 | |
| extern void free_user_ns(struct kref *kref);
 | |
| 
 | |
| static inline void put_user_ns(struct user_namespace *ns)
 | |
| {
 | |
| 	if (ns)
 | |
| 		kref_put(&ns->kref, free_user_ns);
 | |
| }
 | |
| 
 | |
| #else
 | |
| 
 | |
| static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
 | |
| {
 | |
| 	return &init_user_ns;
 | |
| }
 | |
| 
 | |
| static inline int create_user_ns(struct cred *new)
 | |
| {
 | |
| 	return -EINVAL;
 | |
| }
 | |
| 
 | |
| static inline void put_user_ns(struct user_namespace *ns)
 | |
| {
 | |
| }
 | |
| 
 | |
| #endif
 | |
| 
 | |
| #endif /* _LINUX_USER_H */
 |