korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-11 20:48:49 +08:00
Code Issues Packages Projects Releases Wiki Activity

userns: Rename id_map_mutex to userns_state_mutex

Browse Source 
Generalize id_map_mutex so it can be used for more state of a user namespace.

Cc: stable@vger.kernel.org
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This commit is contained in:
Eric W. Biederman 2014-12-09 14:03:14 -06:00
parent f95d7918bd
commit f0d62aec93
1 changed files with 6 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
kernel/user_namespace.c
View File

@ -24,6 +24,7 @@
#include <linux/fs_struct.h>
static struct kmem_cache *user_ns_cachep __read_mostly;
static DEFINE_MUTEX(userns_state_mutex);
static bool new_idmap_permitted(const struct file *file,
struct user_namespace *ns, int cap_setid,
@ -583,9 +584,6 @@ static bool mappings_overlap(struct uid_gid_map *new_map,
return false;
}
static DEFINE_MUTEX(id_map_mutex);
static ssize_t map_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos,
int cap_setid,
@ -602,7 +600,7 @@ static ssize_t map_write(struct file *file, const char __user *buf,
ssize_t ret = -EINVAL;
/*
* The id_map_mutex serializes all writes to any given map.
* The userns_state_mutex serializes all writes to any given map.
*
* Any map is only ever written once.
*
@ -620,7 +618,7 @@ static ssize_t map_write(struct file *file, const char __user *buf,
* order and smp_rmb() is guaranteed that we don't have crazy
* architectures returning stale data.
*/
mutex_lock(&id_map_mutex);
mutex_lock(&userns_state_mutex);
ret = -EPERM;
/* Only allow one successful write to the map */
@ -750,7 +748,7 @@ static ssize_t map_write(struct file *file, const char __user *buf,
*ppos = count;
ret = count;
out:
mutex_unlock(&id_map_mutex);
mutex_unlock(&userns_state_mutex);
if (page)
free_page(page);
return ret;
@ -845,12 +843,12 @@ bool userns_may_setgroups(const struct user_namespace *ns)
{
bool allowed;
mutex_lock(&id_map_mutex);
mutex_lock(&userns_state_mutex);
/* It is not safe to use setgroups until a gid mapping in
* the user namespace has been established.
*/
allowed = ns->gid_map.nr_extents != 0;
mutex_unlock(&id_map_mutex);
mutex_unlock(&userns_state_mutex);
return allowed;
}