1 files changed, 7 insertions, 23 deletions

diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c
index ed0c0431fcd8..c75e3f9d060f 100644
--- a/net/core/netprio_cgroup.c
+++ b/net/core/netprio_cgroup.c
@@ -101,12 +101,10 @@ static int write_update_netdev_table(struct net_device *dev)
         u32 max_len;
         struct netprio_map *map;
 
-        rtnl_lock();
         max_len = atomic_read(&max_prioidx) + 1;
         map = rtnl_dereference(dev->priomap);
         if (!map || map->priomap_len < max_len)
                 ret = extend_netdev_table(dev, max_len);
-        rtnl_unlock();
 
         return ret;
 }
@@ -256,17 +254,17 @@ static int write_priomap(struct cgroup *cgrp, struct cftype *cft,
         if (!dev)
                 goto out_free_devname;
 
+        rtnl_lock();
         ret = write_update_netdev_table(dev);
         if (ret < 0)
                 goto out_put_dev;
 
-        rcu_read_lock();
-        map = rcu_dereference(dev->priomap);
+        map = rtnl_dereference(dev->priomap);
         if (map)
                 map->priomap[prioidx] = priority;
-        rcu_read_unlock();
 
 out_put_dev:
+        rtnl_unlock();
         dev_put(dev);
 
 out_free_devname:
@@ -277,12 +275,6 @@ out_free_devname:
 void net_prio_attach(struct cgroup *cgrp, struct cgroup_taskset *tset)
 {
         struct task_struct *p;
-        char *tmp = kzalloc(sizeof(char) * PATH_MAX, GFP_KERNEL);
-
-        if (!tmp) {
-                pr_warn("Unable to attach cgrp due to alloc failure!\n");
-                return;
-        }
 
         cgroup_taskset_for_each(p, cgrp, tset) {
                 unsigned int fd;
@@ -296,32 +288,24 @@ void net_prio_attach(struct cgroup *cgrp, struct cgroup_taskset *tset)
                         continue;
                 }
 
-                rcu_read_lock();
+                spin_lock(&files->file_lock);
                 fdt = files_fdtable(files);
                 for (fd = 0; fd < fdt->max_fds; fd++) {
-                        char *path;
                         struct file *file;
                         struct socket *sock;
-                        unsigned long s;
-                        int rv, err = 0;
+                        int err;
 
                         file = fcheck_files(files, fd);
                         if (!file)
                                 continue;
 
-                        path = d_path(&file->f_path, tmp, PAGE_SIZE);
-                        rv = sscanf(path, "socket:[%lu]", &s);
-                        if (rv <= 0)
-                                continue;
-
                         sock = sock_from_file(file, &err);
-                        if (!err)
+                        if (sock)
                                 sock_update_netprioidx(sock->sk, p);
                 }
-                rcu_read_unlock();
+                spin_unlock(&files->file_lock);
                 task_unlock(p);
         }
-        kfree(tmp);
 }
 
 static struct cftype ss_files[] = {