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authorLinus Torvalds <torvalds@linux-foundation.org>2025-02-20 10:19:54 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2025-02-20 10:19:54 -0800
commit27eddbf3449026a73d6ed52d55b192bfcf526a03 (patch)
tree18ec1d5c04a718c237322fb1d2cf3d0598d2fe31 /net/core/dev.c
parente9a8cac0bf895efe0bc7b11d174e8dae9b195da8 (diff)
parentdd3188ddc4c49cb234b82439693121d2c1c69c38 (diff)
Merge tag 'net-6.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Paolo Abeni: "Smaller than usual with no fixes from any subtree. Current release - regressions: - core: fix race of rtnl_net_lock(dev_net(dev)) Previous releases - regressions: - core: remove the single page frag cache for good - flow_dissector: fix handling of mixed port and port-range keys - sched: cls_api: fix error handling causing NULL dereference - tcp: - adjust rcvq_space after updating scaling ratio - drop secpath at the same time as we currently drop dst - eth: gtp: suppress list corruption splat in gtp_net_exit_batch_rtnl(). Previous releases - always broken: - vsock: - fix variables initialization during resuming - for connectible sockets allow only connected - eth: - geneve: fix use-after-free in geneve_find_dev() - ibmvnic: don't reference skb after sending to VIOS" * tag 'net-6.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (34 commits) Revert "net: skb: introduce and use a single page frag cache" net: allow small head cache usage with large MAX_SKB_FRAGS values nfp: bpf: Add check for nfp_app_ctrl_msg_alloc() tcp: drop secpath at the same time as we currently drop dst net: axienet: Set mac_managed_pm arp: switch to dev_getbyhwaddr() in arp_req_set_public() net: Add non-RCU dev_getbyhwaddr() helper sctp: Fix undefined behavior in left shift operation selftests/bpf: Add a specific dst port matching flow_dissector: Fix port range key handling in BPF conversion selftests/net/forwarding: Add a test case for tc-flower of mixed port and port-range flow_dissector: Fix handling of mixed port and port-range keys geneve: Suppress list corruption splat in geneve_destroy_tunnels(). gtp: Suppress list corruption splat in gtp_net_exit_batch_rtnl(). dev: Use rtnl_net_dev_lock() in unregister_netdev(). net: Fix dev_net(dev) race in unregister_netdevice_notifier_dev_net(). net: Add net_passive_inc() and net_passive_dec(). net: pse-pd: pd692x0: Fix power limit retrieval MAINTAINERS: trim the GVE entry gve: set xdp redirect target only when it is available ...
Diffstat (limited to 'net/core/dev.c')
-rw-r--r--net/core/dev.c108
1 files changed, 97 insertions, 11 deletions
diff --git a/net/core/dev.c b/net/core/dev.c
index b91658e8aedb..1b252e9459fd 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1121,6 +1121,12 @@ out:
return ret;
}
+static bool dev_addr_cmp(struct net_device *dev, unsigned short type,
+ const char *ha)
+{
+ return dev->type == type && !memcmp(dev->dev_addr, ha, dev->addr_len);
+}
+
/**
* dev_getbyhwaddr_rcu - find a device by its hardware address
* @net: the applicable net namespace
@@ -1129,7 +1135,7 @@ out:
*
* Search for an interface by MAC address. Returns NULL if the device
* is not found or a pointer to the device.
- * The caller must hold RCU or RTNL.
+ * The caller must hold RCU.
* The returned device has not had its ref count increased
* and the caller must therefore be careful about locking
*
@@ -1141,14 +1147,39 @@ struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
struct net_device *dev;
for_each_netdev_rcu(net, dev)
- if (dev->type == type &&
- !memcmp(dev->dev_addr, ha, dev->addr_len))
+ if (dev_addr_cmp(dev, type, ha))
return dev;
return NULL;
}
EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
+/**
+ * dev_getbyhwaddr() - find a device by its hardware address
+ * @net: the applicable net namespace
+ * @type: media type of device
+ * @ha: hardware address
+ *
+ * Similar to dev_getbyhwaddr_rcu(), but the owner needs to hold
+ * rtnl_lock.
+ *
+ * Context: rtnl_lock() must be held.
+ * Return: pointer to the net_device, or NULL if not found
+ */
+struct net_device *dev_getbyhwaddr(struct net *net, unsigned short type,
+ const char *ha)
+{
+ struct net_device *dev;
+
+ ASSERT_RTNL();
+ for_each_netdev(net, dev)
+ if (dev_addr_cmp(dev, type, ha))
+ return dev;
+
+ return NULL;
+}
+EXPORT_SYMBOL(dev_getbyhwaddr);
+
struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
{
struct net_device *dev, *ret = NULL;
@@ -2070,6 +2101,42 @@ static void __move_netdevice_notifier_net(struct net *src_net,
__register_netdevice_notifier_net(dst_net, nb, true);
}
+static void rtnl_net_dev_lock(struct net_device *dev)
+{
+ bool again;
+
+ do {
+ struct net *net;
+
+ again = false;
+
+ /* netns might be being dismantled. */
+ rcu_read_lock();
+ net = dev_net_rcu(dev);
+ net_passive_inc(net);
+ rcu_read_unlock();
+
+ rtnl_net_lock(net);
+
+#ifdef CONFIG_NET_NS
+ /* dev might have been moved to another netns. */
+ if (!net_eq(net, rcu_access_pointer(dev->nd_net.net))) {
+ rtnl_net_unlock(net);
+ net_passive_dec(net);
+ again = true;
+ }
+#endif
+ } while (again);
+}
+
+static void rtnl_net_dev_unlock(struct net_device *dev)
+{
+ struct net *net = dev_net(dev);
+
+ rtnl_net_unlock(net);
+ net_passive_dec(net);
+}
+
int register_netdevice_notifier_dev_net(struct net_device *dev,
struct notifier_block *nb,
struct netdev_net_notifier *nn)
@@ -2077,6 +2144,11 @@ int register_netdevice_notifier_dev_net(struct net_device *dev,
struct net *net = dev_net(dev);
int err;
+ /* rtnl_net_lock() assumes dev is not yet published by
+ * register_netdevice().
+ */
+ DEBUG_NET_WARN_ON_ONCE(!list_empty(&dev->dev_list));
+
rtnl_net_lock(net);
err = __register_netdevice_notifier_net(net, nb, false);
if (!err) {
@@ -2093,13 +2165,12 @@ int unregister_netdevice_notifier_dev_net(struct net_device *dev,
struct notifier_block *nb,
struct netdev_net_notifier *nn)
{
- struct net *net = dev_net(dev);
int err;
- rtnl_net_lock(net);
+ rtnl_net_dev_lock(dev);
list_del(&nn->list);
- err = __unregister_netdevice_notifier_net(net, nb);
- rtnl_net_unlock(net);
+ err = __unregister_netdevice_notifier_net(dev_net(dev), nb);
+ rtnl_net_dev_unlock(dev);
return err;
}
@@ -6920,6 +6991,23 @@ netif_napi_dev_list_add(struct net_device *dev, struct napi_struct *napi)
list_add_rcu(&napi->dev_list, higher); /* adds after higher */
}
+/* Double check that napi_get_frags() allocates skbs with
+ * skb->head being backed by slab, not a page fragment.
+ * This is to make sure bug fixed in 3226b158e67c
+ * ("net: avoid 32 x truesize under-estimation for tiny skbs")
+ * does not accidentally come back.
+ */
+static void napi_get_frags_check(struct napi_struct *napi)
+{
+ struct sk_buff *skb;
+
+ local_bh_disable();
+ skb = napi_get_frags(napi);
+ WARN_ON_ONCE(skb && skb->head_frag);
+ napi_free_frags(napi);
+ local_bh_enable();
+}
+
void netif_napi_add_weight_locked(struct net_device *dev,
struct napi_struct *napi,
int (*poll)(struct napi_struct *, int),
@@ -11880,11 +11968,9 @@ EXPORT_SYMBOL(unregister_netdevice_many);
*/
void unregister_netdev(struct net_device *dev)
{
- struct net *net = dev_net(dev);
-
- rtnl_net_lock(net);
+ rtnl_net_dev_lock(dev);
unregister_netdevice(dev);
- rtnl_net_unlock(net);
+ rtnl_net_dev_unlock(dev);
}
EXPORT_SYMBOL(unregister_netdev);