ALSA: usb-audio: add support for Akai MPD16

[safe/jmp/linux-2.6] / security / device_cgroup.c

diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index cd377b9..8d9c48f 100644 (file)
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -10,7 +10,9 @@
 #include <linux/list.h>
 #include <linux/uaccess.h>
 #include <linux/seq_file.h>
+#include <linux/slab.h>
 #include <linux/rcupdate.h>
+#include <linux/mutex.h>
 
 #define ACC_MKNOD 1
 #define ACC_READ  2
@@ -21,9 +23,11 @@
 #define DEV_CHAR  2
 #define DEV_ALL   4  /* this represents all devices */
 
+static DEFINE_MUTEX(devcgroup_mutex);
+
 /*
  * whitelist locking rules:
- * hold cgroup_lock() for update/read.
+ * hold devcgroup_mutex for update/read.
  * hold rcu_read_lock() for read.
  */
 
@@ -58,7 +62,8 @@ static inline struct dev_cgroup *task_devcgroup(struct task_struct *task)
 struct cgroup_subsys devices_subsys;
 
 static int devcgroup_can_attach(struct cgroup_subsys *ss,
-               struct cgroup *new_cgroup, struct task_struct *task)
+               struct cgroup *new_cgroup, struct task_struct *task,
+               bool threadgroup)
 {
        if (current != task && !capable(CAP_SYS_ADMIN))
                        return -EPERM;
@@ -67,7 +72,7 @@ static int devcgroup_can_attach(struct cgroup_subsys *ss,
 }
 
 /*
- * called under cgroup_lock()
+ * called under devcgroup_mutex
  */
 static int dev_whitelist_copy(struct list_head *dest, struct list_head *orig)
 {
@@ -92,7 +97,7 @@ free_and_exit:
 
 /* Stupid prototype - don't bother combining existing entries */
 /*
- * called under cgroup_lock()
+ * called under devcgroup_mutex
  */
 static int dev_whitelist_add(struct dev_cgroup *dev_cgroup,
                        struct dev_whitelist_item *wh)
@@ -130,7 +135,7 @@ static void whitelist_item_free(struct rcu_head *rcu)
 }
 
 /*
- * called under cgroup_lock()
+ * called under devcgroup_mutex
  */
 static void dev_whitelist_rm(struct dev_cgroup *dev_cgroup,
                        struct dev_whitelist_item *wh)
@@ -185,8 +190,10 @@ static struct cgroup_subsys_state *devcgroup_create(struct cgroup_subsys *ss,
                list_add(&wh->list, &dev_cgroup->whitelist);
        } else {
                parent_dev_cgroup = cgroup_to_devcgroup(parent_cgroup);
+               mutex_lock(&devcgroup_mutex);
                ret = dev_whitelist_copy(&dev_cgroup->whitelist,
                                &parent_dev_cgroup->whitelist);
+               mutex_unlock(&devcgroup_mutex);
                if (ret) {
                        kfree(dev_cgroup);
                        return ERR_PTR(ret);
@@ -273,7 +280,7 @@ static int devcgroup_seq_read(struct cgroup *cgroup, struct cftype *cft,
  * does the access granted to dev_cgroup c contain the access
  * requested in whitelist item refwh.
  * return 1 if yes, 0 if no.
- * call with c->lock held
+ * call with devcgroup_mutex held
  */
 static int may_access_whitelist(struct dev_cgroup *c,
                                       struct dev_whitelist_item *refwh)
@@ -426,11 +433,11 @@ static int devcgroup_access_write(struct cgroup *cgrp, struct cftype *cft,
                                  const char *buffer)
 {
        int retval;
-       if (!cgroup_lock_live_group(cgrp))
-               return -ENODEV;
+
+       mutex_lock(&devcgroup_mutex);
        retval = devcgroup_update_access(cgroup_to_devcgroup(cgrp),
                                         cft->private, buffer);
-       cgroup_unlock();
+       mutex_unlock(&devcgroup_mutex);
        return retval;
 }
 
@@ -463,7 +470,7 @@ struct cgroup_subsys devices_subsys = {
        .name = "devices",
        .can_attach = devcgroup_can_attach,
        .create = devcgroup_create,
-       .destroy  = devcgroup_destroy,
+       .destroy = devcgroup_destroy,
        .populate = devcgroup_populate,
        .subsys_id = devices_subsys_id,
 };
@@ -485,7 +492,7 @@ int devcgroup_inode_permission(struct inode *inode, int mask)
 
        list_for_each_entry_rcu(wh, &dev_cgroup->whitelist, list) {
                if (wh->type & DEV_ALL)
-                       goto acc_check;
+                       goto found;
                if ((wh->type & DEV_BLOCK) && !S_ISBLK(inode->i_mode))
                        continue;
                if ((wh->type & DEV_CHAR) && !S_ISCHR(inode->i_mode))
@@ -494,11 +501,12 @@ int devcgroup_inode_permission(struct inode *inode, int mask)
                        continue;
                if (wh->minor != ~0 && wh->minor != iminor(inode))
                        continue;
-acc_check:
+
                if ((mask & MAY_WRITE) && !(wh->access & ACC_WRITE))
                        continue;
                if ((mask & MAY_READ) && !(wh->access & ACC_READ))
                        continue;
+found:
                rcu_read_unlock();
                return 0;
        }
@@ -513,13 +521,16 @@ int devcgroup_inode_mknod(int mode, dev_t dev)
        struct dev_cgroup *dev_cgroup;
        struct dev_whitelist_item *wh;
 
+       if (!S_ISBLK(mode) && !S_ISCHR(mode))
+               return 0;
+
        rcu_read_lock();
 
        dev_cgroup = task_devcgroup(current);
 
        list_for_each_entry_rcu(wh, &dev_cgroup->whitelist, list) {
                if (wh->type & DEV_ALL)
-                       goto acc_check;
+                       goto found;
                if ((wh->type & DEV_BLOCK) && !S_ISBLK(mode))
                        continue;
                if ((wh->type & DEV_CHAR) && !S_ISCHR(mode))
@@ -528,9 +539,10 @@ int devcgroup_inode_mknod(int mode, dev_t dev)
                        continue;
                if (wh->minor != ~0 && wh->minor != MINOR(dev))
                        continue;
-acc_check:
+
                if (!(wh->access & ACC_MKNOD))
                        continue;
+found:
                rcu_read_unlock();
                return 0;
        }