| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20240325233905.09e8c19d4207.I203795c6b809819c98532e5d6186c700a6c1c760@changeid>
Date: Mon, 25 Mar 2024 23:31:28 +0100
From: Johannes Berg <johannes@...solutions.net>
To: netdev@...r.kernel.org
Cc: Johannes Berg <johannes.berg@...el.com>
Subject: [PATCH 3/3] net: core: use guard/__free in core dev code
From: Johannes Berg <johannes.berg@...el.com>
Simplify the code a bit, mostly also to illustrate
the new helpers.
Signed-off-by: Johannes Berg <johannes.berg@...el.com>
---
net/core/dev.c | 182 +++++++++++++++++++------------------------------
1 file changed, 72 insertions(+), 110 deletions(-)
diff --git a/net/core/dev.c b/net/core/dev.c
index 9a67003e49db..f4f4627bb1e3 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1367,9 +1367,8 @@ EXPORT_SYMBOL(__netdev_notify_peers);
*/
void netdev_notify_peers(struct net_device *dev)
{
- rtnl_lock();
+ guard(rtnl)();
__netdev_notify_peers(dev);
- rtnl_unlock();
}
EXPORT_SYMBOL(netdev_notify_peers);
@@ -1722,30 +1721,27 @@ int register_netdevice_notifier(struct notifier_block *nb)
int err;
/* Close race with setup_net() and cleanup_net() */
- down_write(&pernet_ops_rwsem);
- rtnl_lock();
+ guard(rwsem_write)(&pernet_ops_rwsem);
+ guard(rtnl)();
err = raw_notifier_chain_register(&netdev_chain, nb);
if (err)
- goto unlock;
+ return err;
if (dev_boot_phase)
- goto unlock;
+ return 0;
for_each_net(net) {
err = call_netdevice_register_net_notifiers(nb, net);
if (err)
goto rollback;
}
-unlock:
- rtnl_unlock();
- up_write(&pernet_ops_rwsem);
- return err;
+ return 0;
rollback:
for_each_net_continue_reverse(net)
call_netdevice_unregister_net_notifiers(nb, net);
raw_notifier_chain_unregister(&netdev_chain, nb);
- goto unlock;
+ return err;
}
EXPORT_SYMBOL(register_netdevice_notifier);
@@ -1769,19 +1765,16 @@ int unregister_netdevice_notifier(struct notifier_block *nb)
int err;
/* Close race with setup_net() and cleanup_net() */
- down_write(&pernet_ops_rwsem);
- rtnl_lock();
+ guard(rwsem_write)(&pernet_ops_rwsem);
+ guard(rtnl)();
err = raw_notifier_chain_unregister(&netdev_chain, nb);
if (err)
- goto unlock;
+ return err;
for_each_net(net)
call_netdevice_unregister_net_notifiers(nb, net);
-unlock:
- rtnl_unlock();
- up_write(&pernet_ops_rwsem);
- return err;
+ return 0;
}
EXPORT_SYMBOL(unregister_netdevice_notifier);
@@ -1838,12 +1831,9 @@ static int __unregister_netdevice_notifier_net(struct net *net,
int register_netdevice_notifier_net(struct net *net, struct notifier_block *nb)
{
- int err;
+ guard(rtnl)();
- rtnl_lock();
- err = __register_netdevice_notifier_net(net, nb, false);
- rtnl_unlock();
- return err;
+ return __register_netdevice_notifier_net(net, nb, false);
}
EXPORT_SYMBOL(register_netdevice_notifier_net);
@@ -1866,12 +1856,9 @@ EXPORT_SYMBOL(register_netdevice_notifier_net);
int unregister_netdevice_notifier_net(struct net *net,
struct notifier_block *nb)
{
- int err;
+ guard(rtnl)();
- rtnl_lock();
- err = __unregister_netdevice_notifier_net(net, nb);
- rtnl_unlock();
- return err;
+ return __unregister_netdevice_notifier_net(net, nb);
}
EXPORT_SYMBOL(unregister_netdevice_notifier_net);
@@ -1889,14 +1876,14 @@ int register_netdevice_notifier_dev_net(struct net_device *dev,
{
int err;
- rtnl_lock();
+ guard(rtnl)();
err = __register_netdevice_notifier_net(dev_net(dev), nb, false);
- if (!err) {
- nn->nb = nb;
- list_add(&nn->list, &dev->net_notifier_list);
- }
- rtnl_unlock();
- return err;
+ if (err)
+ return err;
+
+ nn->nb = nb;
+ list_add(&nn->list, &dev->net_notifier_list);
+ return 0;
}
EXPORT_SYMBOL(register_netdevice_notifier_dev_net);
@@ -1904,13 +1891,10 @@ int unregister_netdevice_notifier_dev_net(struct net_device *dev,
struct notifier_block *nb,
struct netdev_net_notifier *nn)
{
- int err;
+ guard(rtnl)();
- rtnl_lock();
list_del(&nn->list);
- err = __unregister_netdevice_notifier_net(dev_net(dev), nb);
- rtnl_unlock();
- return err;
+ return __unregister_netdevice_notifier_net(dev_net(dev), nb);
}
EXPORT_SYMBOL(unregister_netdevice_notifier_dev_net);
@@ -9453,7 +9437,7 @@ static void bpf_xdp_link_release(struct bpf_link *link)
{
struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
- rtnl_lock();
+ guard(rtnl)();
/* if racing with net_device's tear down, xdp_link->dev might be
* already NULL, in which case link was already auto-detached
@@ -9462,8 +9446,6 @@ static void bpf_xdp_link_release(struct bpf_link *link)
WARN_ON(dev_xdp_detach_link(xdp_link->dev, NULL, xdp_link));
xdp_link->dev = NULL;
}
-
- rtnl_unlock();
}
static int bpf_xdp_link_detach(struct bpf_link *link)
@@ -9485,10 +9467,10 @@ static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link,
struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
u32 ifindex = 0;
- rtnl_lock();
- if (xdp_link->dev)
- ifindex = xdp_link->dev->ifindex;
- rtnl_unlock();
+ scoped_guard(rtnl) {
+ if (xdp_link->dev)
+ ifindex = xdp_link->dev->ifindex;
+ }
seq_printf(seq, "ifindex:\t%u\n", ifindex);
}
@@ -9499,10 +9481,10 @@ static int bpf_xdp_link_fill_link_info(const struct bpf_link *link,
struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
u32 ifindex = 0;
- rtnl_lock();
- if (xdp_link->dev)
- ifindex = xdp_link->dev->ifindex;
- rtnl_unlock();
+ scoped_guard(rtnl) {
+ if (xdp_link->dev)
+ ifindex = xdp_link->dev->ifindex;
+ }
info->xdp.ifindex = ifindex;
return 0;
@@ -9514,31 +9496,26 @@ static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog,
struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
enum bpf_xdp_mode mode;
bpf_op_t bpf_op;
- int err = 0;
+ int err;
- rtnl_lock();
+ guard(rtnl)();
/* link might have been auto-released already, so fail */
- if (!xdp_link->dev) {
- err = -ENOLINK;
- goto out_unlock;
- }
+ if (!xdp_link->dev)
+ return -ENOLINK;
+
+ if (old_prog && link->prog != old_prog)
+ return -EPERM;
- if (old_prog && link->prog != old_prog) {
- err = -EPERM;
- goto out_unlock;
- }
old_prog = link->prog;
if (old_prog->type != new_prog->type ||
- old_prog->expected_attach_type != new_prog->expected_attach_type) {
- err = -EINVAL;
- goto out_unlock;
- }
+ old_prog->expected_attach_type != new_prog->expected_attach_type)
+ return -EINVAL;
if (old_prog == new_prog) {
/* no-op, don't disturb drivers */
bpf_prog_put(new_prog);
- goto out_unlock;
+ return 0;
}
mode = dev_xdp_mode(xdp_link->dev, xdp_link->flags);
@@ -9546,14 +9523,11 @@ static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog,
err = dev_xdp_install(xdp_link->dev, mode, bpf_op, NULL,
xdp_link->flags, new_prog);
if (err)
- goto out_unlock;
+ return err;
old_prog = xchg(&link->prog, new_prog);
bpf_prog_put(old_prog);
-
-out_unlock:
- rtnl_unlock();
- return err;
+ return 0;
}
static const struct bpf_link_ops bpf_xdp_link_lops = {
@@ -9567,57 +9541,47 @@ static const struct bpf_link_ops bpf_xdp_link_lops = {
int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
{
+ /* link itself doesn't hold dev's refcnt to not complicate shutdown */
+ struct net_device *dev __free(dev_put) = NULL;
struct net *net = current->nsproxy->net_ns;
struct bpf_link_primer link_primer;
struct netlink_ext_ack extack = {};
struct bpf_xdp_link *link;
- struct net_device *dev;
- int err, fd;
+ int err;
- rtnl_lock();
- dev = dev_get_by_index(net, attr->link_create.target_ifindex);
- if (!dev) {
- rtnl_unlock();
- return -EINVAL;
- }
+ scoped_guard(rtnl) {
+ dev = dev_get_by_index(net,
+ attr->link_create.target_ifindex);
+ if (!dev)
+ return -EINVAL;
- link = kzalloc(sizeof(*link), GFP_USER);
- if (!link) {
- err = -ENOMEM;
- goto unlock;
- }
+ link = kzalloc(sizeof(*link), GFP_USER);
+ if (!link)
+ return -ENOMEM;
- bpf_link_init(&link->link, BPF_LINK_TYPE_XDP, &bpf_xdp_link_lops, prog);
- link->dev = dev;
- link->flags = attr->link_create.flags;
+ bpf_link_init(&link->link, BPF_LINK_TYPE_XDP,
+ &bpf_xdp_link_lops, prog);
- err = bpf_link_prime(&link->link, &link_primer);
- if (err) {
- kfree(link);
- goto unlock;
- }
+ link->dev = dev;
+ link->flags = attr->link_create.flags;
- err = dev_xdp_attach_link(dev, &extack, link);
- rtnl_unlock();
+ err = bpf_link_prime(&link->link, &link_primer);
+ if (err) {
+ kfree(link);
+ return err;
+ }
+
+ err = dev_xdp_attach_link(dev, &extack, link);
+ }
if (err) {
link->dev = NULL;
bpf_link_cleanup(&link_primer);
trace_bpf_xdp_link_attach_failed(extack._msg);
- goto out_put_dev;
+ return err;
}
- fd = bpf_link_settle(&link_primer);
- /* link itself doesn't hold dev's refcnt to not complicate shutdown */
- dev_put(dev);
- return fd;
-
-unlock:
- rtnl_unlock();
-
-out_put_dev:
- dev_put(dev);
- return err;
+ return bpf_link_settle(&link_primer);
}
/**
@@ -11171,9 +11135,8 @@ EXPORT_SYMBOL(unregister_netdevice_many);
*/
void unregister_netdev(struct net_device *dev)
{
- rtnl_lock();
+ guard(rtnl)();
unregister_netdevice(dev);
- rtnl_unlock();
}
EXPORT_SYMBOL(unregister_netdev);
@@ -11617,7 +11580,7 @@ static void __net_exit default_device_exit_batch(struct list_head *net_list)
struct net *net;
LIST_HEAD(dev_kill_list);
- rtnl_lock();
+ guard(rtnl)();
list_for_each_entry(net, net_list, exit_list) {
default_device_exit_net(net);
cond_resched();
@@ -11632,7 +11595,6 @@ static void __net_exit default_device_exit_batch(struct list_head *net_list)
}
}
unregister_netdevice_many(&dev_kill_list);
- rtnl_unlock();
}
static struct pernet_operations __net_initdata default_device_ops = {
--
2.44.0
Powered by blists - more mailing lists