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 */
|