diff --git a/net/core/dev.c b/net/core/dev.c index 5aaf5753d4e4..9f3f8930c691 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -345,7 +345,6 @@ int netdev_name_node_alt_create(struct net_device *dev, const char *name) static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node) { list_del(&name_node->list); - netdev_name_node_del(name_node); kfree(name_node->name); netdev_name_node_free(name_node); } @@ -364,6 +363,8 @@ int netdev_name_node_alt_destroy(struct net_device *dev, const char *name) if (name_node == dev->name_node || name_node->dev != dev) return -EINVAL; + netdev_name_node_del(name_node); + synchronize_rcu(); __netdev_name_node_alt_destroy(name_node); return 0; @@ -380,6 +381,7 @@ static void netdev_name_node_alt_flush(struct net_device *dev) /* Device list insertion */ static void list_netdevice(struct net_device *dev) { + struct netdev_name_node *name_node; struct net *net = dev_net(dev); ASSERT_RTNL(); @@ -390,6 +392,10 @@ static void list_netdevice(struct net_device *dev) hlist_add_head_rcu(&dev->index_hlist, dev_index_hash(net, dev->ifindex)); write_unlock(&dev_base_lock); + + netdev_for_each_altname(dev, name_node) + netdev_name_node_add(net, name_node); + /* We reserved the ifindex, this can't fail */ WARN_ON(xa_store(&net->dev_by_index, dev->ifindex, dev, GFP_KERNEL)); @@ -401,12 +407,16 @@ static void list_netdevice(struct net_device *dev) */ static void unlist_netdevice(struct net_device *dev, bool lock) { + struct netdev_name_node *name_node; struct net *net = dev_net(dev); ASSERT_RTNL(); xa_erase(&net->dev_by_index, dev->ifindex); + netdev_for_each_altname(dev, name_node) + netdev_name_node_del(name_node); + /* Unlink dev from the device chain */ if (lock) write_lock(&dev_base_lock); @@ -1086,7 +1096,8 @@ static int __dev_alloc_name(struct net *net, const char *name, char *buf) for_each_netdev(net, d) { struct netdev_name_node *name_node; - list_for_each_entry(name_node, &d->name_node->list, list) { + + netdev_for_each_altname(d, name_node) { if (!sscanf(name_node->name, name, &i)) continue; if (i < 0 || i >= max_netdevices) @@ -1123,6 +1134,26 @@ static int __dev_alloc_name(struct net *net, const char *name, char *buf) return -ENFILE; } +static int dev_prep_valid_name(struct net *net, struct net_device *dev, + const char *want_name, char *out_name) +{ + int ret; + + if (!dev_valid_name(want_name)) + return -EINVAL; + + if (strchr(want_name, '%')) { + ret = __dev_alloc_name(net, want_name, out_name); + return ret < 0 ? ret : 0; + } else if (netdev_name_in_use(net, want_name)) { + return -EEXIST; + } else if (out_name != want_name) { + strscpy(out_name, want_name, IFNAMSIZ); + } + + return 0; +} + static int dev_alloc_name_ns(struct net *net, struct net_device *dev, const char *name) @@ -1160,19 +1191,13 @@ EXPORT_SYMBOL(dev_alloc_name); static int dev_get_valid_name(struct net *net, struct net_device *dev, const char *name) { - BUG_ON(!net); + char buf[IFNAMSIZ]; + int ret; - if (!dev_valid_name(name)) - return -EINVAL; - - if (strchr(name, '%')) - return dev_alloc_name_ns(net, dev, name); - else if (netdev_name_in_use(net, name)) - return -EEXIST; - else if (dev->name != name) - strscpy(dev->name, name, IFNAMSIZ); - - return 0; + ret = dev_prep_valid_name(net, dev, name, buf); + if (ret >= 0) + strscpy(dev->name, buf, IFNAMSIZ); + return ret; } /** @@ -11037,7 +11062,9 @@ EXPORT_SYMBOL(unregister_netdev); int __dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat, int new_ifindex) { + struct netdev_name_node *name_node; struct net *net_old = dev_net(dev); + char new_name[IFNAMSIZ] = {}; int err, new_nsid; ASSERT_RTNL(); @@ -11064,10 +11091,15 @@ int __dev_change_net_namespace(struct net_device *dev, struct net *net, /* We get here if we can't use the current device name */ if (!pat) goto out; - err = dev_get_valid_name(net, dev, pat); + err = dev_prep_valid_name(net, dev, pat, new_name); if (err < 0) goto out; } + /* Check that none of the altnames conflicts. */ + err = -EEXIST; + netdev_for_each_altname(dev, name_node) + if (netdev_name_in_use(net, name_node->name)) + goto out; /* Check that new_ifindex isn't used yet. */ if (new_ifindex) { @@ -11135,6 +11167,9 @@ int __dev_change_net_namespace(struct net_device *dev, struct net *net, kobject_uevent(&dev->dev.kobj, KOBJ_ADD); netdev_adjacent_add_links(dev); + if (new_name[0]) /* Rename the netdev to prepared name */ + strscpy(dev->name, new_name, IFNAMSIZ); + /* Fixup kobjects */ err = device_rename(&dev->dev, dev->name); WARN_ON(err); diff --git a/net/core/dev.h b/net/core/dev.h index e075e198092c..fa2e9c5c4122 100644 --- a/net/core/dev.h +++ b/net/core/dev.h @@ -62,6 +62,9 @@ struct netdev_name_node { int netdev_get_name(struct net *net, char *name, int ifindex); int dev_change_name(struct net_device *dev, const char *newname); +#define netdev_for_each_altname(dev, namenode) \ + list_for_each_entry((namenode), &(dev)->name_node->list, list) + int netdev_name_node_alt_create(struct net_device *dev, const char *name); int netdev_name_node_alt_destroy(struct net_device *dev, const char *name); diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile index 8b017070960d..4a2881d43989 100644 --- a/tools/testing/selftests/net/Makefile +++ b/tools/testing/selftests/net/Makefile @@ -34,6 +34,7 @@ TEST_PROGS += gro.sh TEST_PROGS += gre_gso.sh TEST_PROGS += cmsg_so_mark.sh TEST_PROGS += cmsg_time.sh cmsg_ipv6.sh +TEST_PROGS += netns-name.sh TEST_PROGS += srv6_end_dt46_l3vpn_test.sh TEST_PROGS += srv6_end_dt4_l3vpn_test.sh TEST_PROGS += srv6_end_dt6_l3vpn_test.sh diff --git a/tools/testing/selftests/net/netns-name.sh b/tools/testing/selftests/net/netns-name.sh new file mode 100755 index 000000000000..7d3d3fc99461 --- /dev/null +++ b/tools/testing/selftests/net/netns-name.sh @@ -0,0 +1,87 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +set -o pipefail + +NS=netns-name-test +DEV=dummy-dev0 +DEV2=dummy-dev1 +ALT_NAME=some-alt-name + +RET_CODE=0 + +cleanup() { + ip netns del $NS +} + +trap cleanup EXIT + +fail() { + echo "ERROR: ${1:-unexpected return code} (ret: $_)" >&2 + RET_CODE=1 +} + +ip netns add $NS + +# +# Test basic move without a rename +# +ip -netns $NS link add name $DEV type dummy || fail +ip -netns $NS link set dev $DEV netns 1 || + fail "Can't perform a netns move" +ip link show dev $DEV >> /dev/null || fail "Device not found after move" +ip link del $DEV || fail + +# +# Test move with a conflict +# +ip link add name $DEV type dummy +ip -netns $NS link add name $DEV type dummy || fail +ip -netns $NS link set dev $DEV netns 1 2> /dev/null && + fail "Performed a netns move with a name conflict" +ip link show dev $DEV >> /dev/null || fail "Device not found after move" +ip -netns $NS link del $DEV || fail +ip link del $DEV || fail + +# +# Test move with a conflict and rename +# +ip link add name $DEV type dummy +ip -netns $NS link add name $DEV type dummy || fail +ip -netns $NS link set dev $DEV netns 1 name $DEV2 || + fail "Can't perform a netns move with rename" +ip link del $DEV2 || fail +ip link del $DEV || fail + +# +# Test dup alt-name with netns move +# +ip link add name $DEV type dummy || fail +ip link property add dev $DEV altname $ALT_NAME || fail +ip -netns $NS link add name $DEV2 type dummy || fail +ip -netns $NS link property add dev $DEV2 altname $ALT_NAME || fail + +ip -netns $NS link set dev $DEV2 netns 1 2> /dev/null && + fail "Moved with alt-name dup" + +ip link del $DEV || fail +ip -netns $NS link del $DEV2 || fail + +# +# Test creating alt-name in one net-ns and using in another +# +ip -netns $NS link add name $DEV type dummy || fail +ip -netns $NS link property add dev $DEV altname $ALT_NAME || fail +ip -netns $NS link set dev $DEV netns 1 || fail +ip link show dev $ALT_NAME >> /dev/null || fail "Can't find alt-name after move" +ip -netns $NS link show dev $ALT_NAME 2> /dev/null && + fail "Can still find alt-name after move" +ip link del $DEV || fail + +echo -ne "$(basename $0) \t\t\t\t" +if [ $RET_CODE -eq 0 ]; then + echo "[ OK ]" +else + echo "[ FAIL ]" +fi +exit $RET_CODE