Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f796c20c authored by John Fastabend's avatar John Fastabend Committed by David S. Miller
Browse files

net: netprio: fix files lock and remove useless d_path bits 



Add lock to prevent a race with a file closing and also remove
useless and ugly sscanf code. The extra code was never needed
and the case it supposedly protected against is in fact handled
correctly by sock_from_file as pointed out by Al Viro.

CC: Neil Horman <nhorman@tuxdriver.com>
Reported-by: default avatarAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: default avatarJohn Fastabend <john.r.fastabend@intel.com>
Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 16c0b164

net/core/netprio_cgroup.c

+4 −18
Original line number Diff line number Diff line
@@ -277,12 +277,6 @@ 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 +290,24 @@ 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[] = {