From 171526f6fee84de0c39e2b7aa7e666ba0bbfd173 Mon Sep 17 00:00:00 2001 From: Jakub Sitnicki Date: Sun, 31 May 2020 10:28:35 +0200 Subject: flow_dissector: Pull locking up from prog attach callback Split out the part of attach callback that happens with attach/detach lock acquired. This structures the prog attach callback in a way that opens up doors for moving the locking out of flow_dissector and into generic callbacks for attaching/detaching progs to netns in subsequent patches. Signed-off-by: Jakub Sitnicki Signed-off-by: Alexei Starovoitov Reviewed-by: Stanislav Fomichev Link: https://lore.kernel.org/bpf/20200531082846.2117903-2-jakub@cloudflare.com --- net/core/flow_dissector.c | 40 ++++++++++++++++++++-------------------- 1 file changed, 20 insertions(+), 20 deletions(-) (limited to 'net') diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 0aeb33572feb..b64a44a083fd 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -109,15 +109,10 @@ int skb_flow_dissector_prog_query(const union bpf_attr *attr, return 0; } -int skb_flow_dissector_bpf_prog_attach(const union bpf_attr *attr, - struct bpf_prog *prog) +static int flow_dissector_bpf_prog_attach(struct net *net, + struct bpf_prog *prog) { struct bpf_prog *attached; - struct net *net; - int ret = 0; - - net = current->nsproxy->net_ns; - mutex_lock(&flow_dissector_mutex); if (net == &init_net) { /* BPF flow dissector in the root namespace overrides @@ -130,33 +125,38 @@ int skb_flow_dissector_bpf_prog_attach(const union bpf_attr *attr, for_each_net(ns) { if (ns == &init_net) continue; - if (rcu_access_pointer(ns->flow_dissector_prog)) { - ret = -EEXIST; - goto out; - } + if (rcu_access_pointer(ns->flow_dissector_prog)) + return -EEXIST; } } else { /* Make sure root flow dissector is not attached * when attaching to the non-root namespace. */ - if (rcu_access_pointer(init_net.flow_dissector_prog)) { - ret = -EEXIST; - goto out; - } + if (rcu_access_pointer(init_net.flow_dissector_prog)) + return -EEXIST; } attached = rcu_dereference_protected(net->flow_dissector_prog, lockdep_is_held(&flow_dissector_mutex)); - if (attached == prog) { + if (attached == prog) /* The same program cannot be attached twice */ - ret = -EINVAL; - goto out; - } + return -EINVAL; + rcu_assign_pointer(net->flow_dissector_prog, prog); if (attached) bpf_prog_put(attached); -out: + return 0; +} + +int skb_flow_dissector_bpf_prog_attach(const union bpf_attr *attr, + struct bpf_prog *prog) +{ + int ret; + + mutex_lock(&flow_dissector_mutex); + ret = flow_dissector_bpf_prog_attach(current->nsproxy->net_ns, prog); mutex_unlock(&flow_dissector_mutex); + return ret; } -- cgit v1.2.3 From a3fd7ceee05431d2c51ed86c6cae015d236a51f0 Mon Sep 17 00:00:00 2001 From: Jakub Sitnicki Date: Sun, 31 May 2020 10:28:36 +0200 Subject: net: Introduce netns_bpf for BPF programs attached to netns In order to: (1) attach more than one BPF program type to netns, or (2) support attaching BPF programs to netns with bpf_link, or (3) support multi-prog attach points for netns we will need to keep more state per netns than a single pointer like we have now for BPF flow dissector program. Prepare for the above by extracting netns_bpf that is part of struct net, for storing all state related to BPF programs attached to netns. Turn flow dissector callbacks for querying/attaching/detaching a program into generic ones that operate on netns_bpf. Next patch will move the generic callbacks into their own module. This is similar to how it is organized for cgroup with cgroup_bpf. Signed-off-by: Jakub Sitnicki Signed-off-by: Alexei Starovoitov Cc: Stanislav Fomichev Link: https://lore.kernel.org/bpf/20200531082846.2117903-3-jakub@cloudflare.com --- include/linux/bpf-netns.h | 56 +++++++++++++++++++++++ include/linux/skbuff.h | 26 ----------- include/net/net_namespace.h | 4 +- include/net/netns/bpf.h | 17 +++++++ kernel/bpf/syscall.c | 7 +-- net/core/flow_dissector.c | 105 +++++++++++++++++++++++++++++--------------- 6 files changed, 149 insertions(+), 66 deletions(-) create mode 100644 include/linux/bpf-netns.h create mode 100644 include/net/netns/bpf.h (limited to 'net') diff --git a/include/linux/bpf-netns.h b/include/linux/bpf-netns.h new file mode 100644 index 000000000000..f3aec3d79824 --- /dev/null +++ b/include/linux/bpf-netns.h @@ -0,0 +1,56 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _BPF_NETNS_H +#define _BPF_NETNS_H + +#include +#include + +enum netns_bpf_attach_type { + NETNS_BPF_INVALID = -1, + NETNS_BPF_FLOW_DISSECTOR = 0, + MAX_NETNS_BPF_ATTACH_TYPE +}; + +static inline enum netns_bpf_attach_type +to_netns_bpf_attach_type(enum bpf_attach_type attach_type) +{ + switch (attach_type) { + case BPF_FLOW_DISSECTOR: + return NETNS_BPF_FLOW_DISSECTOR; + default: + return NETNS_BPF_INVALID; + } +} + +/* Protects updates to netns_bpf */ +extern struct mutex netns_bpf_mutex; + +union bpf_attr; +struct bpf_prog; + +#ifdef CONFIG_NET +int netns_bpf_prog_query(const union bpf_attr *attr, + union bpf_attr __user *uattr); +int netns_bpf_prog_attach(const union bpf_attr *attr, + struct bpf_prog *prog); +int netns_bpf_prog_detach(const union bpf_attr *attr); +#else +static inline int netns_bpf_prog_query(const union bpf_attr *attr, + union bpf_attr __user *uattr) +{ + return -EOPNOTSUPP; +} + +static inline int netns_bpf_prog_attach(const union bpf_attr *attr, + struct bpf_prog *prog) +{ + return -EOPNOTSUPP; +} + +static inline int netns_bpf_prog_detach(const union bpf_attr *attr) +{ + return -EOPNOTSUPP; +} +#endif + +#endif /* _BPF_NETNS_H */ diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 531843952809..a0d5c2760103 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1283,32 +1283,6 @@ void skb_flow_dissector_init(struct flow_dissector *flow_dissector, const struct flow_dissector_key *key, unsigned int key_count); -#ifdef CONFIG_NET -int skb_flow_dissector_prog_query(const union bpf_attr *attr, - union bpf_attr __user *uattr); -int skb_flow_dissector_bpf_prog_attach(const union bpf_attr *attr, - struct bpf_prog *prog); - -int skb_flow_dissector_bpf_prog_detach(const union bpf_attr *attr); -#else -static inline int skb_flow_dissector_prog_query(const union bpf_attr *attr, - union bpf_attr __user *uattr) -{ - return -EOPNOTSUPP; -} - -static inline int skb_flow_dissector_bpf_prog_attach(const union bpf_attr *attr, - struct bpf_prog *prog) -{ - return -EOPNOTSUPP; -} - -static inline int skb_flow_dissector_bpf_prog_detach(const union bpf_attr *attr) -{ - return -EOPNOTSUPP; -} -#endif - struct bpf_flow_dissector; bool bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx, __be16 proto, int nhoff, int hlen, unsigned int flags); diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 8e001e049497..2ee5901bec7a 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -33,6 +33,7 @@ #include #include #include +#include #include #include #include @@ -162,7 +163,8 @@ struct net { #endif struct net_generic __rcu *gen; - struct bpf_prog __rcu *flow_dissector_prog; + /* Used to store attached BPF programs */ + struct netns_bpf bpf; /* Note : following structs are cache line aligned */ #ifdef CONFIG_XFRM diff --git a/include/net/netns/bpf.h b/include/net/netns/bpf.h new file mode 100644 index 000000000000..a858d1c5b166 --- /dev/null +++ b/include/net/netns/bpf.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * BPF programs attached to network namespace + */ + +#ifndef __NETNS_BPF_H__ +#define __NETNS_BPF_H__ + +#include + +struct bpf_prog; + +struct netns_bpf { + struct bpf_prog __rcu *progs[MAX_NETNS_BPF_ATTACH_TYPE]; +}; + +#endif /* __NETNS_BPF_H__ */ diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index e83b0818b529..c77ab9c76f7b 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -27,6 +27,7 @@ #include #include #include +#include #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \ @@ -2868,7 +2869,7 @@ static int bpf_prog_attach(const union bpf_attr *attr) ret = lirc_prog_attach(attr, prog); break; case BPF_PROG_TYPE_FLOW_DISSECTOR: - ret = skb_flow_dissector_bpf_prog_attach(attr, prog); + ret = netns_bpf_prog_attach(attr, prog); break; case BPF_PROG_TYPE_CGROUP_DEVICE: case BPF_PROG_TYPE_CGROUP_SKB: @@ -2908,7 +2909,7 @@ static int bpf_prog_detach(const union bpf_attr *attr) case BPF_PROG_TYPE_FLOW_DISSECTOR: if (!capable(CAP_NET_ADMIN)) return -EPERM; - return skb_flow_dissector_bpf_prog_detach(attr); + return netns_bpf_prog_detach(attr); case BPF_PROG_TYPE_CGROUP_DEVICE: case BPF_PROG_TYPE_CGROUP_SKB: case BPF_PROG_TYPE_CGROUP_SOCK: @@ -2961,7 +2962,7 @@ static int bpf_prog_query(const union bpf_attr *attr, case BPF_LIRC_MODE2: return lirc_prog_query(attr, uattr); case BPF_FLOW_DISSECTOR: - return skb_flow_dissector_prog_query(attr, uattr); + return netns_bpf_prog_query(attr, uattr); default: return -EINVAL; } diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index b64a44a083fd..6c1b8e43d611 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -31,8 +31,10 @@ #include #include #endif +#include -static DEFINE_MUTEX(flow_dissector_mutex); +/* Protects updates to netns_bpf */ +DEFINE_MUTEX(netns_bpf_mutex); static void dissector_set_key(struct flow_dissector *flow_dissector, enum flow_dissector_key_id key_id) @@ -70,23 +72,28 @@ void skb_flow_dissector_init(struct flow_dissector *flow_dissector, } EXPORT_SYMBOL(skb_flow_dissector_init); -int skb_flow_dissector_prog_query(const union bpf_attr *attr, - union bpf_attr __user *uattr) +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->flow_dissector_prog); + attached = rcu_dereference(net->bpf.progs[type]); if (attached) { prog_cnt = 1; prog_id = attached->aux->id; @@ -112,6 +119,7 @@ int skb_flow_dissector_prog_query(const union bpf_attr *attr, static int flow_dissector_bpf_prog_attach(struct net *net, struct bpf_prog *prog) { + enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR; struct bpf_prog *attached; if (net == &init_net) { @@ -125,74 +133,97 @@ static int flow_dissector_bpf_prog_attach(struct net *net, for_each_net(ns) { if (ns == &init_net) continue; - if (rcu_access_pointer(ns->flow_dissector_prog)) + if (rcu_access_pointer(ns->bpf.progs[type])) return -EEXIST; } } else { /* Make sure root flow dissector is not attached * when attaching to the non-root namespace. */ - if (rcu_access_pointer(init_net.flow_dissector_prog)) + if (rcu_access_pointer(init_net.bpf.progs[type])) return -EEXIST; } - attached = rcu_dereference_protected(net->flow_dissector_prog, - lockdep_is_held(&flow_dissector_mutex)); + attached = rcu_dereference_protected(net->bpf.progs[type], + lockdep_is_held(&netns_bpf_mutex)); if (attached == prog) /* The same program cannot be attached twice */ return -EINVAL; - rcu_assign_pointer(net->flow_dissector_prog, prog); + rcu_assign_pointer(net->bpf.progs[type], prog); if (attached) bpf_prog_put(attached); return 0; } -int skb_flow_dissector_bpf_prog_attach(const union bpf_attr *attr, - struct bpf_prog *prog) +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; - mutex_lock(&flow_dissector_mutex); - ret = flow_dissector_bpf_prog_attach(current->nsproxy->net_ns, prog); - mutex_unlock(&flow_dissector_mutex); + type = to_netns_bpf_attach_type(attr->attach_type); + if (type < 0) + return -EINVAL; + + net = current->nsproxy->net_ns; + mutex_lock(&netns_bpf_mutex); + switch (type) { + case NETNS_BPF_FLOW_DISSECTOR: + ret = flow_dissector_bpf_prog_attach(net, prog); + break; + default: + ret = -EINVAL; + break; + } + mutex_unlock(&netns_bpf_mutex); return ret; } -static int flow_dissector_bpf_prog_detach(struct net *net) +/* 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; - mutex_lock(&flow_dissector_mutex); - attached = rcu_dereference_protected(net->flow_dissector_prog, - lockdep_is_held(&flow_dissector_mutex)); - if (!attached) { - mutex_unlock(&flow_dissector_mutex); + attached = rcu_dereference_protected(net->bpf.progs[type], + lockdep_is_held(&netns_bpf_mutex)); + if (!attached) return -ENOENT; - } - RCU_INIT_POINTER(net->flow_dissector_prog, NULL); + RCU_INIT_POINTER(net->bpf.progs[type], NULL); bpf_prog_put(attached); - mutex_unlock(&flow_dissector_mutex); return 0; } -int skb_flow_dissector_bpf_prog_detach(const union bpf_attr *attr) +int netns_bpf_prog_detach(const union bpf_attr *attr) { - return flow_dissector_bpf_prog_detach(current->nsproxy->net_ns); + 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 void __net_exit flow_dissector_pernet_pre_exit(struct net *net) +static void __net_exit netns_bpf_pernet_pre_exit(struct net *net) { - /* We're not racing with attach/detach because there are no - * references to netns left when pre_exit gets called. - */ - if (rcu_access_pointer(net->flow_dissector_prog)) - flow_dissector_bpf_prog_detach(net); + enum netns_bpf_attach_type type; + + mutex_lock(&netns_bpf_mutex); + for (type = 0; type < MAX_NETNS_BPF_ATTACH_TYPE; type++) + __netns_bpf_prog_detach(net, type); + mutex_unlock(&netns_bpf_mutex); } -static struct pernet_operations flow_dissector_pernet_ops __net_initdata = { - .pre_exit = flow_dissector_pernet_pre_exit, +static struct pernet_operations netns_bpf_pernet_ops __net_initdata = { + .pre_exit = netns_bpf_pernet_pre_exit, }; /** @@ -1044,11 +1075,13 @@ bool __skb_flow_dissect(const struct net *net, WARN_ON_ONCE(!net); if (net) { + enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR; + rcu_read_lock(); - attached = rcu_dereference(init_net.flow_dissector_prog); + attached = rcu_dereference(init_net.bpf.progs[type]); if (!attached) - attached = rcu_dereference(net->flow_dissector_prog); + attached = rcu_dereference(net->bpf.progs[type]); if (attached) { struct bpf_flow_keys flow_keys; @@ -1870,6 +1903,6 @@ static int __init init_default_flow_dissectors(void) flow_keys_basic_dissector_keys, ARRAY_SIZE(flow_keys_basic_dissector_keys)); - return register_pernet_subsys(&flow_dissector_pernet_ops); + return register_pernet_subsys(&netns_bpf_pernet_ops); } core_initcall(init_default_flow_dissectors); -- cgit v1.2.3 From b27f7bb590ba835b32ef122389db158e44cfda1e Mon Sep 17 00:00:00 2001 From: Jakub Sitnicki Date: Sun, 31 May 2020 10:28:37 +0200 Subject: flow_dissector: Move out netns_bpf prog callbacks Move functions to manage BPF programs attached to netns that are not specific to flow dissector to a dedicated module named bpf/net_namespace.c. The set of functions will grow with the addition of bpf_link support for netns attached programs. This patch prepares ground by creating a place for it. This is a code move with no functional changes intended. Signed-off-by: Jakub Sitnicki Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200531082846.2117903-4-jakub@cloudflare.com --- include/net/flow_dissector.h | 6 ++ kernel/bpf/Makefile | 1 + kernel/bpf/net_namespace.c | 133 +++++++++++++++++++++++++++++++++++++++++++ net/core/flow_dissector.c | 125 ++-------------------------------------- 4 files changed, 144 insertions(+), 121 deletions(-) create mode 100644 kernel/bpf/net_namespace.c (limited to 'net') diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h index 4fb1a69c6ecf..a7eba43fe4e4 100644 --- a/include/net/flow_dissector.h +++ b/include/net/flow_dissector.h @@ -8,6 +8,8 @@ #include #include +struct bpf_prog; +struct net; struct sk_buff; /** @@ -369,4 +371,8 @@ flow_dissector_init_keys(struct flow_dissector_key_control *key_control, memset(key_basic, 0, sizeof(*key_basic)); } +#ifdef CONFIG_BPF_SYSCALL +int flow_dissector_bpf_prog_attach(struct net *net, struct bpf_prog *prog); +#endif /* CONFIG_BPF_SYSCALL */ + #endif diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index 8fca02f64811..1131a921e1a6 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -13,6 +13,7 @@ ifeq ($(CONFIG_NET),y) obj-$(CONFIG_BPF_SYSCALL) += devmap.o obj-$(CONFIG_BPF_SYSCALL) += cpumap.o obj-$(CONFIG_BPF_SYSCALL) += offload.o +obj-$(CONFIG_BPF_SYSCALL) += net_namespace.o endif ifeq ($(CONFIG_PERF_EVENTS),y) obj-$(CONFIG_BPF_SYSCALL) += stackmap.o diff --git a/kernel/bpf/net_namespace.c b/kernel/bpf/net_namespace.c new file mode 100644 index 000000000000..b37d81450c3a --- /dev/null +++ b/kernel/bpf/net_namespace.c @@ -0,0 +1,133 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include + +/* + * Functions to manage BPF programs attached to netns + */ + +/* Protects updates to netns_bpf */ +DEFINE_MUTEX(netns_bpf_mutex); + +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); + switch (type) { + case NETNS_BPF_FLOW_DISSECTOR: + ret = flow_dissector_bpf_prog_attach(net, prog); + break; + default: + ret = -EINVAL; + break; + } + 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; + + 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 void __net_exit netns_bpf_pernet_pre_exit(struct net *net) +{ + enum netns_bpf_attach_type type; + + mutex_lock(&netns_bpf_mutex); + for (type = 0; type < MAX_NETNS_BPF_ATTACH_TYPE; type++) + __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); diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 6c1b8e43d611..d02df0b6d0d9 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -33,9 +33,6 @@ #endif #include -/* Protects updates to netns_bpf */ -DEFINE_MUTEX(netns_bpf_mutex); - static void dissector_set_key(struct flow_dissector *flow_dissector, enum flow_dissector_key_id key_id) { @@ -72,52 +69,8 @@ void skb_flow_dissector_init(struct flow_dissector *flow_dissector, } EXPORT_SYMBOL(skb_flow_dissector_init); -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; -} - -static int flow_dissector_bpf_prog_attach(struct net *net, - struct bpf_prog *prog) +#ifdef CONFIG_BPF_SYSCALL +int flow_dissector_bpf_prog_attach(struct net *net, struct bpf_prog *prog) { enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR; struct bpf_prog *attached; @@ -155,76 +108,7 @@ static int flow_dissector_bpf_prog_attach(struct net *net, bpf_prog_put(attached); 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); - switch (type) { - case NETNS_BPF_FLOW_DISSECTOR: - ret = flow_dissector_bpf_prog_attach(net, prog); - break; - default: - ret = -EINVAL; - break; - } - 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; - - 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 void __net_exit netns_bpf_pernet_pre_exit(struct net *net) -{ - enum netns_bpf_attach_type type; - - mutex_lock(&netns_bpf_mutex); - for (type = 0; type < MAX_NETNS_BPF_ATTACH_TYPE; type++) - __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, -}; +#endif /* CONFIG_BPF_SYSCALL */ /** * __skb_flow_get_ports - extract the upper layer ports and return them @@ -1902,7 +1786,6 @@ static int __init init_default_flow_dissectors(void) skb_flow_dissector_init(&flow_keys_basic_dissector, flow_keys_basic_dissector_keys, ARRAY_SIZE(flow_keys_basic_dissector_keys)); - - return register_pernet_subsys(&netns_bpf_pernet_ops); + return 0; } core_initcall(init_default_flow_dissectors); -- cgit v1.2.3