Merge tag 'spi-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/misc

[mirror_ubuntu-jammy-kernel.git] / net / core / dev.c

diff --git a/net/core/dev.c b/net/core/dev.c
index 0ebaea16632fc348f6a48789831b737c7c51b707..a39354ee14322e5b300646f3866329d22fc20bc8 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1055,6 +1055,8 @@ rollback:
  */
 int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
 {
+       char *new_ifalias;
+
        ASSERT_RTNL();
 
        if (len >= IFALIASZ)
@@ -1068,9 +1070,10 @@ int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
                return 0;
        }
 
-       dev->ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
-       if (!dev->ifalias)
+       new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
+       if (!new_ifalias)
                return -ENOMEM;
+       dev->ifalias = new_ifalias;
 
        strlcpy(dev->ifalias, alias, len+1);
        return len;
@@ -1172,6 +1175,7 @@ static int __dev_open(struct net_device *dev)
                net_dmaengine_get();
                dev_set_rx_mode(dev);
                dev_activate(dev);
+               add_device_randomness(dev->dev_addr, dev->addr_len);
        }
 
        return ret;
@@ -2133,6 +2137,9 @@ netdev_features_t netif_skb_features(struct sk_buff *skb)
        __be16 protocol = skb->protocol;
        netdev_features_t features = skb->dev->features;
 
+       if (skb_shinfo(skb)->gso_segs > skb->dev->gso_max_segs)
+               features &= ~NETIF_F_GSO_MASK;
+
        if (protocol == htons(ETH_P_8021Q)) {
                struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
                protocol = veh->h_vlan_encapsulated_proto;
@@ -3155,6 +3162,23 @@ void netdev_rx_handler_unregister(struct net_device *dev)
 }
 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
 
+/*
+ * Limit the use of PFMEMALLOC reserves to those protocols that implement
+ * the special handling of PFMEMALLOC skbs.
+ */
+static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
+{
+       switch (skb->protocol) {
+       case __constant_htons(ETH_P_ARP):
+       case __constant_htons(ETH_P_IP):
+       case __constant_htons(ETH_P_IPV6):
+       case __constant_htons(ETH_P_8021Q):
+               return true;
+       default:
+               return false;
+       }
+}
+
 static int __netif_receive_skb(struct sk_buff *skb)
 {
        struct packet_type *ptype, *pt_prev;
@@ -3164,14 +3188,27 @@ static int __netif_receive_skb(struct sk_buff *skb)
        bool deliver_exact = false;
        int ret = NET_RX_DROP;
        __be16 type;
+       unsigned long pflags = current->flags;
 
        net_timestamp_check(!netdev_tstamp_prequeue, skb);
 
        trace_netif_receive_skb(skb);
 
+       /*
+        * PFMEMALLOC skbs are special, they should
+        * - be delivered to SOCK_MEMALLOC sockets only
+        * - stay away from userspace
+        * - have bounded memory usage
+        *
+        * Use PF_MEMALLOC as this saves us from propagating the allocation
+        * context down to all allocation sites.
+        */
+       if (sk_memalloc_socks() && skb_pfmemalloc(skb))
+               current->flags |= PF_MEMALLOC;
+
        /* if we've gotten here through NAPI, check netpoll */
        if (netpoll_receive_skb(skb))
-               return NET_RX_DROP;
+               goto out;
 
        orig_dev = skb->dev;
 
@@ -3191,7 +3228,7 @@ another_round:
        if (skb->protocol == cpu_to_be16(ETH_P_8021Q)) {
                skb = vlan_untag(skb);
                if (unlikely(!skb))
-                       goto out;
+                       goto unlock;
        }
 
 #ifdef CONFIG_NET_CLS_ACT
@@ -3201,6 +3238,9 @@ another_round:
        }
 #endif
 
+       if (sk_memalloc_socks() && skb_pfmemalloc(skb))
+               goto skip_taps;
+
        list_for_each_entry_rcu(ptype, &ptype_all, list) {
                if (!ptype->dev || ptype->dev == skb->dev) {
                        if (pt_prev)
@@ -3209,13 +3249,18 @@ another_round:
                }
        }
 
+skip_taps:
 #ifdef CONFIG_NET_CLS_ACT
        skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
        if (!skb)
-               goto out;
+               goto unlock;
 ncls:
 #endif
 
+       if (sk_memalloc_socks() && skb_pfmemalloc(skb)
+                               && !skb_pfmemalloc_protocol(skb))
+               goto drop;
+
        rx_handler = rcu_dereference(skb->dev->rx_handler);
        if (vlan_tx_tag_present(skb)) {
                if (pt_prev) {
@@ -3225,7 +3270,7 @@ ncls:
                if (vlan_do_receive(&skb, !rx_handler))
                        goto another_round;
                else if (unlikely(!skb))
-                       goto out;
+                       goto unlock;
        }
 
        if (rx_handler) {
@@ -3235,7 +3280,7 @@ ncls:
                }
                switch (rx_handler(&skb)) {
                case RX_HANDLER_CONSUMED:
-                       goto out;
+                       goto unlock;
                case RX_HANDLER_ANOTHER:
                        goto another_round;
                case RX_HANDLER_EXACT:
@@ -3268,6 +3313,7 @@ ncls:
                else
                        ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
        } else {
+drop:
                atomic_long_inc(&skb->dev->rx_dropped);
                kfree_skb(skb);
                /* Jamal, now you will not able to escape explaining
@@ -3276,8 +3322,10 @@ ncls:
                ret = NET_RX_DROP;
        }
 
-out:
+unlock:
        rcu_read_unlock();
+out:
+       tsk_restore_flags(current, pflags, PF_MEMALLOC);
        return ret;
 }
 
@@ -4801,6 +4849,7 @@ int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
        err = ops->ndo_set_mac_address(dev, sa);
        if (!err)
                call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
+       add_device_randomness(dev->dev_addr, dev->addr_len);
        return err;
 }
 EXPORT_SYMBOL(dev_set_mac_address);
@@ -5579,6 +5628,7 @@ int register_netdevice(struct net_device *dev)
        dev_init_scheduler(dev);
        dev_hold(dev);
        list_netdevice(dev);
+       add_device_randomness(dev->dev_addr, dev->addr_len);
 
        /* Notify protocols, that a new device appeared. */
        ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
@@ -5942,6 +5992,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
        dev_net_set(dev, &init_net);
 
        dev->gso_max_size = GSO_MAX_SIZE;
+       dev->gso_max_segs = GSO_MAX_SEGS;
 
        INIT_LIST_HEAD(&dev->napi_list);
        INIT_LIST_HEAD(&dev->unreg_list);