nsfs: use cleanup guard

Ensure that rcu read lock is given up before returning.

Link: https://lore.kernel.org/r/20240716-elixier-fliesen-1ab342151a61@brauner
Fixes: ca567df74a ("nsfs: add pid translation ioctls")
Reported-by: syzbot+a3e82ae343b26b4d2335@syzkaller.appspotmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
This commit is contained in:
Christian Brauner 2024-07-16 09:19:11 +02:00
parent 400e4064b6
commit 280e36f0d5
No known key found for this signature in database
GPG key ID: 91C61BC06578DCA2

View file

@ -174,14 +174,14 @@ static long ns_ioctl(struct file *filp, unsigned int ioctl,
fallthrough;
case NS_GET_PID_IN_PIDNS:
fallthrough;
case NS_GET_TGID_IN_PIDNS:
case NS_GET_TGID_IN_PIDNS: {
if (ns->ops->type != CLONE_NEWPID)
return -EINVAL;
ret = -ESRCH;
pid_ns = container_of(ns, struct pid_namespace, ns);
rcu_read_lock();
guard(rcu)();
if (ioctl == NS_GET_PID_IN_PIDNS ||
ioctl == NS_GET_TGID_IN_PIDNS)
@ -208,11 +208,11 @@ static long ns_ioctl(struct file *filp, unsigned int ioctl,
ret = 0;
break;
}
rcu_read_unlock();
if (!ret)
ret = -ESRCH;
break;
}
default:
ret = -ENOTTY;
}