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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-06-03 16:27:18 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-06-03 16:27:18 -0700 |
| commit | cb8e59cc87201af93dfbb6c3dccc8fcad72a09c2 (patch) | |
| tree | a334db9022f89654b777bbce8c4c6632e65b9031 /kernel/bpf/net_namespace.c | |
| parent | Merge branch 'uaccess.comedi' of git://git.kernel.org/pub/scm/linux/kernel/gi... (diff) | |
| parent | selftests: net: ip_defrag: ignore EPERM (diff) | |
| download | linux-cb8e59cc87201af93dfbb6c3dccc8fcad72a09c2.tar.gz linux-cb8e59cc87201af93dfbb6c3dccc8fcad72a09c2.zip | |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:
1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
Augusto von Dentz.
2) Add GSO partial support to igc, from Sasha Neftin.
3) Several cleanups and improvements to r8169 from Heiner Kallweit.
4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
device self-test. From Andrew Lunn.
5) Start moving away from custom driver versions, use the globally
defined kernel version instead, from Leon Romanovsky.
6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.
7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.
8) Add sriov and vf support to hinic, from Luo bin.
9) Support Media Redundancy Protocol (MRP) in the bridging code, from
Horatiu Vultur.
10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.
11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
Dubroca. Also add ipv6 support for espintcp.
12) Lots of ReST conversions of the networking documentation, from Mauro
Carvalho Chehab.
13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
from Doug Berger.
14) Allow to dump cgroup id and filter by it in inet_diag code, from
Dmitry Yakunin.
15) Add infrastructure to export netlink attribute policies to
userspace, from Johannes Berg.
16) Several optimizations to sch_fq scheduler, from Eric Dumazet.
17) Fallback to the default qdisc if qdisc init fails because otherwise
a packet scheduler init failure will make a device inoperative. From
Jesper Dangaard Brouer.
18) Several RISCV bpf jit optimizations, from Luke Nelson.
19) Correct the return type of the ->ndo_start_xmit() method in several
drivers, it's netdev_tx_t but many drivers were using
'int'. From Yunjian Wang.
20) Add an ethtool interface for PHY master/slave config, from Oleksij
Rempel.
21) Add BPF iterators, from Yonghang Song.
22) Add cable test infrastructure, including ethool interfaces, from
Andrew Lunn. Marvell PHY driver is the first to support this
facility.
23) Remove zero-length arrays all over, from Gustavo A. R. Silva.
24) Calculate and maintain an explicit frame size in XDP, from Jesper
Dangaard Brouer.
25) Add CAP_BPF, from Alexei Starovoitov.
26) Support terse dumps in the packet scheduler, from Vlad Buslov.
27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.
28) Add devm_register_netdev(), from Bartosz Golaszewski.
29) Minimize qdisc resets, from Cong Wang.
30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
eliminate set_fs/get_fs calls. From Christoph Hellwig.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
selftests: net: ip_defrag: ignore EPERM
net_failover: fixed rollback in net_failover_open()
Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
vmxnet3: allow rx flow hash ops only when rss is enabled
hinic: add set_channels ethtool_ops support
selftests/bpf: Add a default $(CXX) value
tools/bpf: Don't use $(COMPILE.c)
bpf, selftests: Use bpf_probe_read_kernel
s390/bpf: Use bcr 0,%0 as tail call nop filler
s390/bpf: Maintain 8-byte stack alignment
selftests/bpf: Fix verifier test
selftests/bpf: Fix sample_cnt shared between two threads
bpf, selftests: Adapt cls_redirect to call csum_level helper
bpf: Add csum_level helper for fixing up csum levels
bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
crypto/chtls: IPv6 support for inline TLS
Crypto/chcr: Fixes a coccinile check error
Crypto/chcr: Fixes compilations warnings
...
Diffstat (limited to 'kernel/bpf/net_namespace.c')
| -rw-r--r-- | kernel/bpf/net_namespace.c | 373 |
1 files changed, 373 insertions, 0 deletions
diff --git a/kernel/bpf/net_namespace.c b/kernel/bpf/net_namespace.c new file mode 100644 index 000000000000..78cf061f8179 --- /dev/null +++ b/kernel/bpf/net_namespace.c @@ -0,0 +1,373 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/bpf.h> +#include <linux/filter.h> +#include <net/net_namespace.h> + +/* + * Functions to manage BPF programs attached to netns + */ + +struct bpf_netns_link { + struct bpf_link link; + enum bpf_attach_type type; + enum netns_bpf_attach_type netns_type; + + /* We don't hold a ref to net in order to auto-detach the link + * when netns is going away. Instead we rely on pernet + * pre_exit callback to clear this pointer. Must be accessed + * with netns_bpf_mutex held. + */ + struct net *net; +}; + +/* Protects updates to netns_bpf */ +DEFINE_MUTEX(netns_bpf_mutex); + +/* Must be called with netns_bpf_mutex held. */ +static void __net_exit bpf_netns_link_auto_detach(struct bpf_link *link) +{ + struct bpf_netns_link *net_link = + container_of(link, struct bpf_netns_link, link); + + net_link->net = NULL; +} + +static void bpf_netns_link_release(struct bpf_link *link) +{ + struct bpf_netns_link *net_link = + container_of(link, struct bpf_netns_link, link); + enum netns_bpf_attach_type type = net_link->netns_type; + struct net *net; + + /* Link auto-detached by dying netns. */ + if (!net_link->net) + return; + + mutex_lock(&netns_bpf_mutex); + + /* Recheck after potential sleep. We can race with cleanup_net + * here, but if we see a non-NULL struct net pointer pre_exit + * has not happened yet and will block on netns_bpf_mutex. + */ + net = net_link->net; + if (!net) + goto out_unlock; + + net->bpf.links[type] = NULL; + RCU_INIT_POINTER(net->bpf.progs[type], NULL); + +out_unlock: + mutex_unlock(&netns_bpf_mutex); +} + +static void bpf_netns_link_dealloc(struct bpf_link *link) +{ + struct bpf_netns_link *net_link = + container_of(link, struct bpf_netns_link, link); + + kfree(net_link); +} + +static int bpf_netns_link_update_prog(struct bpf_link *link, + struct bpf_prog *new_prog, + struct bpf_prog *old_prog) +{ + struct bpf_netns_link *net_link = + container_of(link, struct bpf_netns_link, link); + enum netns_bpf_attach_type type = net_link->netns_type; + struct net *net; + int ret = 0; + + if (old_prog && old_prog != link->prog) + return -EPERM; + if (new_prog->type != link->prog->type) + return -EINVAL; + + mutex_lock(&netns_bpf_mutex); + + net = net_link->net; + if (!net || !check_net(net)) { + /* Link auto-detached or netns dying */ + ret = -ENOLINK; + goto out_unlock; + } + + old_prog = xchg(&link->prog, new_prog); + rcu_assign_pointer(net->bpf.progs[type], new_prog); + bpf_prog_put(old_prog); + +out_unlock: + mutex_unlock(&netns_bpf_mutex); + return ret; +} + +static int bpf_netns_link_fill_info(const struct bpf_link *link, + struct bpf_link_info *info) +{ + const struct bpf_netns_link *net_link = + container_of(link, struct bpf_netns_link, link); + unsigned int inum = 0; + struct net *net; + + mutex_lock(&netns_bpf_mutex); + net = net_link->net; + if (net && check_net(net)) + inum = net->ns.inum; + mutex_unlock(&netns_bpf_mutex); + + info->netns.netns_ino = inum; + info->netns.attach_type = net_link->type; + return 0; +} + +static void bpf_netns_link_show_fdinfo(const struct bpf_link *link, + struct seq_file *seq) +{ + struct bpf_link_info info = {}; + + bpf_netns_link_fill_info(link, &info); + seq_printf(seq, + "netns_ino:\t%u\n" + "attach_type:\t%u\n", + info.netns.netns_ino, + info.netns.attach_type); +} + +static const struct bpf_link_ops bpf_netns_link_ops = { + .release = bpf_netns_link_release, + .dealloc = bpf_netns_link_dealloc, + .update_prog = bpf_netns_link_update_prog, + .fill_link_info = bpf_netns_link_fill_info, + .show_fdinfo = bpf_netns_link_show_fdinfo, +}; + +int netns_bpf_prog_query(const union bpf_attr *attr, + union bpf_attr __user *uattr) +{ + __u32 __user *prog_ids = u64_to_user_ptr(attr->query.prog_ids); + u32 prog_id, prog_cnt = 0, flags = 0; + enum netns_bpf_attach_type type; + struct bpf_prog *attached; + struct net *net; + + if (attr->query.query_flags) + return -EINVAL; + + type = to_netns_bpf_attach_type(attr->query.attach_type); + if (type < 0) + return -EINVAL; + + net = get_net_ns_by_fd(attr->query.target_fd); + if (IS_ERR(net)) + return PTR_ERR(net); + + rcu_read_lock(); + attached = rcu_dereference(net->bpf.progs[type]); + if (attached) { + prog_cnt = 1; + prog_id = attached->aux->id; + } + rcu_read_unlock(); + + put_net(net); + + if (copy_to_user(&uattr->query.attach_flags, &flags, sizeof(flags))) + return -EFAULT; + if (copy_to_user(&uattr->query.prog_cnt, &prog_cnt, sizeof(prog_cnt))) + return -EFAULT; + + if (!attr->query.prog_cnt || !prog_ids || !prog_cnt) + return 0; + + if (copy_to_user(prog_ids, &prog_id, sizeof(u32))) + return -EFAULT; + + return 0; +} + +int netns_bpf_prog_attach(const union bpf_attr *attr, struct bpf_prog *prog) +{ + enum netns_bpf_attach_type type; + struct net *net; + int ret; + + type = to_netns_bpf_attach_type(attr->attach_type); + if (type < 0) + return -EINVAL; + + net = current->nsproxy->net_ns; + mutex_lock(&netns_bpf_mutex); + + /* Attaching prog directly is not compatible with links */ + if (net->bpf.links[type]) { + ret = -EEXIST; + goto out_unlock; + } + + switch (type) { + case NETNS_BPF_FLOW_DISSECTOR: + ret = flow_dissector_bpf_prog_attach(net, prog); + break; + default: + ret = -EINVAL; + break; + } +out_unlock: + mutex_unlock(&netns_bpf_mutex); + + return ret; +} + +/* Must be called with netns_bpf_mutex held. */ +static int __netns_bpf_prog_detach(struct net *net, + enum netns_bpf_attach_type type) +{ + struct bpf_prog *attached; + + /* Progs attached via links cannot be detached */ + if (net->bpf.links[type]) + return -EINVAL; + + attached = rcu_dereference_protected(net->bpf.progs[type], + lockdep_is_held(&netns_bpf_mutex)); + if (!attached) + return -ENOENT; + RCU_INIT_POINTER(net->bpf.progs[type], NULL); + bpf_prog_put(attached); + return 0; +} + +int netns_bpf_prog_detach(const union bpf_attr *attr) +{ + enum netns_bpf_attach_type type; + int ret; + + type = to_netns_bpf_attach_type(attr->attach_type); + if (type < 0) + return -EINVAL; + + mutex_lock(&netns_bpf_mutex); + ret = __netns_bpf_prog_detach(current->nsproxy->net_ns, type); + mutex_unlock(&netns_bpf_mutex); + + return ret; +} + +static int netns_bpf_link_attach(struct net *net, struct bpf_link *link, + enum netns_bpf_attach_type type) +{ + struct bpf_prog *prog; + int err; + + mutex_lock(&netns_bpf_mutex); + + /* Allow attaching only one prog or link for now */ + if (net->bpf.links[type]) { + err = -E2BIG; + goto out_unlock; + } + /* Links are not compatible with attaching prog directly */ + prog = rcu_dereference_protected(net->bpf.progs[type], + lockdep_is_held(&netns_bpf_mutex)); + if (prog) { + err = -EEXIST; + goto out_unlock; + } + + switch (type) { + case NETNS_BPF_FLOW_DISSECTOR: + err = flow_dissector_bpf_prog_attach(net, link->prog); + break; + default: + err = -EINVAL; + break; + } + if (err) + goto out_unlock; + + net->bpf.links[type] = link; + +out_unlock: + mutex_unlock(&netns_bpf_mutex); + return err; +} + +int netns_bpf_link_create(const union bpf_attr *attr, struct bpf_prog *prog) +{ + enum netns_bpf_attach_type netns_type; + struct bpf_link_primer link_primer; + struct bpf_netns_link *net_link; + enum bpf_attach_type type; + struct net *net; + int err; + + if (attr->link_create.flags) + return -EINVAL; + + type = attr->link_create.attach_type; + netns_type = to_netns_bpf_attach_type(type); + if (netns_type < 0) + return -EINVAL; + + net = get_net_ns_by_fd(attr->link_create.target_fd); + if (IS_ERR(net)) + return PTR_ERR(net); + + net_link = kzalloc(sizeof(*net_link), GFP_USER); + if (!net_link) { + err = -ENOMEM; + goto out_put_net; + } + bpf_link_init(&net_link->link, BPF_LINK_TYPE_NETNS, + &bpf_netns_link_ops, prog); + net_link->net = net; + net_link->type = type; + net_link->netns_type = netns_type; + + err = bpf_link_prime(&net_link->link, &link_primer); + if (err) { + kfree(net_link); + goto out_put_net; + } + + err = netns_bpf_link_attach(net, &net_link->link, netns_type); + if (err) { + bpf_link_cleanup(&link_primer); + goto out_put_net; + } + + put_net(net); + return bpf_link_settle(&link_primer); + +out_put_net: + put_net(net); + return err; +} + +static void __net_exit netns_bpf_pernet_pre_exit(struct net *net) +{ + enum netns_bpf_attach_type type; + struct bpf_link *link; + + mutex_lock(&netns_bpf_mutex); + for (type = 0; type < MAX_NETNS_BPF_ATTACH_TYPE; type++) { + link = net->bpf.links[type]; + if (link) + bpf_netns_link_auto_detach(link); + else + __netns_bpf_prog_detach(net, type); + } + mutex_unlock(&netns_bpf_mutex); +} + +static struct pernet_operations netns_bpf_pernet_ops __net_initdata = { + .pre_exit = netns_bpf_pernet_pre_exit, +}; + +static int __init netns_bpf_init(void) +{ + return register_pernet_subsys(&netns_bpf_pernet_ops); +} + +subsys_initcall(netns_bpf_init); |
