diff options
author | Jakub Kicinski <kuba@kernel.org> | 2023-08-04 01:34:36 +0300 |
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committer | Jakub Kicinski <kuba@kernel.org> | 2023-08-04 01:34:36 +0300 |
commit | d07b7b32da6f678d42d96a8b9824cf0a181ce140 (patch) | |
tree | 606829d4b33a57dbe0f0e825ca8505e0b5fcb759 /net/netfilter | |
parent | 35b1b1fd96388d5e3cf179bf36bd8a4153baf4a3 (diff) | |
parent | 648880e9331c68b2008430fd90f3648d1795399d (diff) | |
download | linux-d07b7b32da6f678d42d96a8b9824cf0a181ce140.tar.xz |
Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Martin KaFai Lau says:
====================
pull-request: bpf-next 2023-08-03
We've added 54 non-merge commits during the last 10 day(s) which contain
a total of 84 files changed, 4026 insertions(+), 562 deletions(-).
The main changes are:
1) Add SO_REUSEPORT support for TC bpf_sk_assign from Lorenz Bauer,
Daniel Borkmann
2) Support new insns from cpu v4 from Yonghong Song
3) Non-atomically allocate freelist during prefill from YiFei Zhu
4) Support defragmenting IPv(4|6) packets in BPF from Daniel Xu
5) Add tracepoint to xdp attaching failure from Leon Hwang
6) struct netdev_rx_queue and xdp.h reshuffling to reduce
rebuild time from Jakub Kicinski
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (54 commits)
net: invert the netdevice.h vs xdp.h dependency
net: move struct netdev_rx_queue out of netdevice.h
eth: add missing xdp.h includes in drivers
selftests/bpf: Add testcase for xdp attaching failure tracepoint
bpf, xdp: Add tracepoint to xdp attaching failure
selftests/bpf: fix static assert compilation issue for test_cls_*.c
bpf: fix bpf_probe_read_kernel prototype mismatch
riscv, bpf: Adapt bpf trampoline to optimized riscv ftrace framework
libbpf: fix typos in Makefile
tracing: bpf: use struct trace_entry in struct syscall_tp_t
bpf, devmap: Remove unused dtab field from bpf_dtab_netdev
bpf, cpumap: Remove unused cmap field from bpf_cpu_map_entry
netfilter: bpf: Only define get_proto_defrag_hook() if necessary
bpf: Fix an array-index-out-of-bounds issue in disasm.c
net: remove duplicate INDIRECT_CALLABLE_DECLARE of udp[6]_ehashfn
docs/bpf: Fix malformed documentation
bpf: selftests: Add defrag selftests
bpf: selftests: Support custom type and proto for client sockets
bpf: selftests: Support not connecting client socket
netfilter: bpf: Support BPF_F_NETFILTER_IP_DEFRAG in netfilter link
...
====================
Link: https://lore.kernel.org/r/20230803174845.825419-1-martin.lau@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/netfilter')
-rw-r--r-- | net/netfilter/core.c | 6 | ||||
-rw-r--r-- | net/netfilter/nf_bpf_link.c | 125 | ||||
-rw-r--r-- | net/netfilter/nf_conntrack_bpf.c | 1 |
3 files changed, 117 insertions, 15 deletions
diff --git a/net/netfilter/core.c b/net/netfilter/core.c index 5f76ae86a656..ef4e76e5aef9 100644 --- a/net/netfilter/core.c +++ b/net/netfilter/core.c @@ -680,6 +680,12 @@ EXPORT_SYMBOL_GPL(nfnl_ct_hook); const struct nf_ct_hook __rcu *nf_ct_hook __read_mostly; EXPORT_SYMBOL_GPL(nf_ct_hook); +const struct nf_defrag_hook __rcu *nf_defrag_v4_hook __read_mostly; +EXPORT_SYMBOL_GPL(nf_defrag_v4_hook); + +const struct nf_defrag_hook __rcu *nf_defrag_v6_hook __read_mostly; +EXPORT_SYMBOL_GPL(nf_defrag_v6_hook); + #if IS_ENABLED(CONFIG_NF_CONNTRACK) u8 nf_ctnetlink_has_listener; EXPORT_SYMBOL_GPL(nf_ctnetlink_has_listener); diff --git a/net/netfilter/nf_bpf_link.c b/net/netfilter/nf_bpf_link.c index c36da56d756f..e502ec00b2fe 100644 --- a/net/netfilter/nf_bpf_link.c +++ b/net/netfilter/nf_bpf_link.c @@ -1,6 +1,8 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/bpf.h> #include <linux/filter.h> +#include <linux/kmod.h> +#include <linux/module.h> #include <linux/netfilter.h> #include <net/netfilter/nf_bpf_link.h> @@ -23,8 +25,90 @@ struct bpf_nf_link { struct nf_hook_ops hook_ops; struct net *net; u32 dead; + const struct nf_defrag_hook *defrag_hook; }; +#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV4) || IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) +static const struct nf_defrag_hook * +get_proto_defrag_hook(struct bpf_nf_link *link, + const struct nf_defrag_hook __rcu *global_hook, + const char *mod) +{ + const struct nf_defrag_hook *hook; + int err; + + /* RCU protects us from races against module unloading */ + rcu_read_lock(); + hook = rcu_dereference(global_hook); + if (!hook) { + rcu_read_unlock(); + err = request_module(mod); + if (err) + return ERR_PTR(err < 0 ? err : -EINVAL); + + rcu_read_lock(); + hook = rcu_dereference(global_hook); + } + + if (hook && try_module_get(hook->owner)) { + /* Once we have a refcnt on the module, we no longer need RCU */ + hook = rcu_pointer_handoff(hook); + } else { + WARN_ONCE(!hook, "%s has bad registration", mod); + hook = ERR_PTR(-ENOENT); + } + rcu_read_unlock(); + + if (!IS_ERR(hook)) { + err = hook->enable(link->net); + if (err) { + module_put(hook->owner); + hook = ERR_PTR(err); + } + } + + return hook; +} +#endif + +static int bpf_nf_enable_defrag(struct bpf_nf_link *link) +{ + const struct nf_defrag_hook __maybe_unused *hook; + + switch (link->hook_ops.pf) { +#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV4) + case NFPROTO_IPV4: + hook = get_proto_defrag_hook(link, nf_defrag_v4_hook, "nf_defrag_ipv4"); + if (IS_ERR(hook)) + return PTR_ERR(hook); + + link->defrag_hook = hook; + return 0; +#endif +#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) + case NFPROTO_IPV6: + hook = get_proto_defrag_hook(link, nf_defrag_v6_hook, "nf_defrag_ipv6"); + if (IS_ERR(hook)) + return PTR_ERR(hook); + + link->defrag_hook = hook; + return 0; +#endif + default: + return -EAFNOSUPPORT; + } +} + +static void bpf_nf_disable_defrag(struct bpf_nf_link *link) +{ + const struct nf_defrag_hook *hook = link->defrag_hook; + + if (!hook) + return; + hook->disable(link->net); + module_put(hook->owner); +} + static void bpf_nf_link_release(struct bpf_link *link) { struct bpf_nf_link *nf_link = container_of(link, struct bpf_nf_link, link); @@ -32,11 +116,11 @@ static void bpf_nf_link_release(struct bpf_link *link) if (nf_link->dead) return; - /* prevent hook-not-found warning splat from netfilter core when - * .detach was already called - */ - if (!cmpxchg(&nf_link->dead, 0, 1)) + /* do not double release in case .detach was already called */ + if (!cmpxchg(&nf_link->dead, 0, 1)) { nf_unregister_net_hook(nf_link->net, &nf_link->hook_ops); + bpf_nf_disable_defrag(nf_link); + } } static void bpf_nf_link_dealloc(struct bpf_link *link) @@ -92,6 +176,8 @@ static const struct bpf_link_ops bpf_nf_link_lops = { static int bpf_nf_check_pf_and_hooks(const union bpf_attr *attr) { + int prio; + switch (attr->link_create.netfilter.pf) { case NFPROTO_IPV4: case NFPROTO_IPV6: @@ -102,19 +188,18 @@ static int bpf_nf_check_pf_and_hooks(const union bpf_attr *attr) return -EAFNOSUPPORT; } - if (attr->link_create.netfilter.flags) + if (attr->link_create.netfilter.flags & ~BPF_F_NETFILTER_IP_DEFRAG) return -EOPNOTSUPP; - /* make sure conntrack confirm is always last. - * - * In the future, if userspace can e.g. request defrag, then - * "defrag_requested && prio before NF_IP_PRI_CONNTRACK_DEFRAG" - * should fail. - */ - switch (attr->link_create.netfilter.priority) { - case NF_IP_PRI_FIRST: return -ERANGE; /* sabotage_in and other warts */ - case NF_IP_PRI_LAST: return -ERANGE; /* e.g. conntrack confirm */ - } + /* make sure conntrack confirm is always last */ + prio = attr->link_create.netfilter.priority; + if (prio == NF_IP_PRI_FIRST) + return -ERANGE; /* sabotage_in and other warts */ + else if (prio == NF_IP_PRI_LAST) + return -ERANGE; /* e.g. conntrack confirm */ + else if ((attr->link_create.netfilter.flags & BPF_F_NETFILTER_IP_DEFRAG) && + prio <= NF_IP_PRI_CONNTRACK_DEFRAG) + return -ERANGE; /* cannot use defrag if prog runs before nf_defrag */ return 0; } @@ -149,6 +234,7 @@ int bpf_nf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) link->net = net; link->dead = false; + link->defrag_hook = NULL; err = bpf_link_prime(&link->link, &link_primer); if (err) { @@ -156,8 +242,17 @@ int bpf_nf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) return err; } + if (attr->link_create.netfilter.flags & BPF_F_NETFILTER_IP_DEFRAG) { + err = bpf_nf_enable_defrag(link); + if (err) { + bpf_link_cleanup(&link_primer); + return err; + } + } + err = nf_register_net_hook(net, &link->hook_ops); if (err) { + bpf_nf_disable_defrag(link); bpf_link_cleanup(&link_primer); return err; } diff --git a/net/netfilter/nf_conntrack_bpf.c b/net/netfilter/nf_conntrack_bpf.c index 0d36d7285e3f..c7a6114091ae 100644 --- a/net/netfilter/nf_conntrack_bpf.c +++ b/net/netfilter/nf_conntrack_bpf.c @@ -14,6 +14,7 @@ #include <linux/types.h> #include <linux/btf_ids.h> #include <linux/net_namespace.h> +#include <net/xdp.h> #include <net/netfilter/nf_conntrack_bpf.h> #include <net/netfilter/nf_conntrack_core.h> |