diff options
Diffstat (limited to 'net/core/filter.c')
-rw-r--r-- | net/core/filter.c | 195 |
1 files changed, 174 insertions, 21 deletions
diff --git a/net/core/filter.c b/net/core/filter.c index 3b728ab79a61..adfdad234674 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2083,13 +2083,13 @@ static const struct bpf_func_proto bpf_csum_level_proto = { static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb) { - return dev_forward_skb(dev, skb); + return dev_forward_skb_nomtu(dev, skb); } static inline int __bpf_rx_skb_no_mac(struct net_device *dev, struct sk_buff *skb) { - int ret = ____dev_forward_skb(dev, skb); + int ret = ____dev_forward_skb(dev, skb, false); if (likely(!ret)) { skb->dev = dev; @@ -2480,7 +2480,7 @@ int skb_do_redirect(struct sk_buff *skb) goto out_drop; dev = ops->ndo_get_peer_dev(dev); if (unlikely(!dev || - !is_skb_forwardable(dev, skb) || + !(dev->flags & IFF_UP) || net_eq(net, dev_net(dev)))) goto out_drop; skb->dev = dev; @@ -3552,11 +3552,7 @@ static int bpf_skb_net_shrink(struct sk_buff *skb, u32 off, u32 len_diff, return 0; } -static u32 __bpf_skb_max_len(const struct sk_buff *skb) -{ - return skb->dev ? skb->dev->mtu + skb->dev->hard_header_len : - SKB_MAX_ALLOC; -} +#define BPF_SKB_MAX_LEN SKB_MAX_ALLOC BPF_CALL_4(sk_skb_adjust_room, struct sk_buff *, skb, s32, len_diff, u32, mode, u64, flags) @@ -3605,7 +3601,7 @@ BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff, { u32 len_cur, len_diff_abs = abs(len_diff); u32 len_min = bpf_skb_net_base_len(skb); - u32 len_max = __bpf_skb_max_len(skb); + u32 len_max = BPF_SKB_MAX_LEN; __be16 proto = skb->protocol; bool shrink = len_diff < 0; u32 off; @@ -3688,7 +3684,7 @@ static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len) static inline int __bpf_skb_change_tail(struct sk_buff *skb, u32 new_len, u64 flags) { - u32 max_len = __bpf_skb_max_len(skb); + u32 max_len = BPF_SKB_MAX_LEN; u32 min_len = __bpf_skb_min_len(skb); int ret; @@ -3764,7 +3760,7 @@ static const struct bpf_func_proto sk_skb_change_tail_proto = { static inline int __bpf_skb_change_head(struct sk_buff *skb, u32 head_room, u64 flags) { - u32 max_len = __bpf_skb_max_len(skb); + u32 max_len = BPF_SKB_MAX_LEN; u32 new_len = skb->len + head_room; int ret; @@ -4631,6 +4627,18 @@ static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = { .arg1_type = ARG_PTR_TO_CTX, }; +BPF_CALL_1(bpf_get_socket_ptr_cookie, struct sock *, sk) +{ + return sk ? sock_gen_cookie(sk) : 0; +} + +const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto = { + .func = bpf_get_socket_ptr_cookie, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON, +}; + BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx) { return __sock_gen_cookie(ctx->sk); @@ -5291,12 +5299,14 @@ static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = { #if IS_ENABLED(CONFIG_INET) || IS_ENABLED(CONFIG_IPV6) static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params, const struct neighbour *neigh, - const struct net_device *dev) + const struct net_device *dev, u32 mtu) { memcpy(params->dmac, neigh->ha, ETH_ALEN); memcpy(params->smac, dev->dev_addr, ETH_ALEN); params->h_vlan_TCI = 0; params->h_vlan_proto = 0; + if (mtu) + params->mtu_result = mtu; /* union with tot_len */ return 0; } @@ -5312,8 +5322,8 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params, struct net_device *dev; struct fib_result res; struct flowi4 fl4; + u32 mtu = 0; int err; - u32 mtu; dev = dev_get_by_index_rcu(net, params->ifindex); if (unlikely(!dev)) @@ -5380,8 +5390,10 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params, if (check_mtu) { mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst); - if (params->tot_len > mtu) + if (params->tot_len > mtu) { + params->mtu_result = mtu; /* union with tot_len */ return BPF_FIB_LKUP_RET_FRAG_NEEDED; + } } nhc = res.nhc; @@ -5415,7 +5427,7 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params, if (!neigh) return BPF_FIB_LKUP_RET_NO_NEIGH; - return bpf_fib_set_fwd_params(params, neigh, dev); + return bpf_fib_set_fwd_params(params, neigh, dev, mtu); } #endif @@ -5432,7 +5444,7 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params, struct flowi6 fl6; int strict = 0; int oif, err; - u32 mtu; + u32 mtu = 0; /* link local addresses are never forwarded */ if (rt6_need_strict(dst) || rt6_need_strict(src)) @@ -5507,8 +5519,10 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params, if (check_mtu) { mtu = ipv6_stub->ip6_mtu_from_fib6(&res, dst, src); - if (params->tot_len > mtu) + if (params->tot_len > mtu) { + params->mtu_result = mtu; /* union with tot_len */ return BPF_FIB_LKUP_RET_FRAG_NEEDED; + } } if (res.nh->fib_nh_lws) @@ -5528,7 +5542,7 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params, if (!neigh) return BPF_FIB_LKUP_RET_NO_NEIGH; - return bpf_fib_set_fwd_params(params, neigh, dev); + return bpf_fib_set_fwd_params(params, neigh, dev, mtu); } #endif @@ -5571,6 +5585,7 @@ BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb, { struct net *net = dev_net(skb->dev); int rc = -EAFNOSUPPORT; + bool check_mtu = false; if (plen < sizeof(*params)) return -EINVAL; @@ -5578,25 +5593,33 @@ BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb, if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT)) return -EINVAL; + if (params->tot_len) + check_mtu = true; + switch (params->family) { #if IS_ENABLED(CONFIG_INET) case AF_INET: - rc = bpf_ipv4_fib_lookup(net, params, flags, false); + rc = bpf_ipv4_fib_lookup(net, params, flags, check_mtu); break; #endif #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: - rc = bpf_ipv6_fib_lookup(net, params, flags, false); + rc = bpf_ipv6_fib_lookup(net, params, flags, check_mtu); break; #endif } - if (!rc) { + if (rc == BPF_FIB_LKUP_RET_SUCCESS && !check_mtu) { struct net_device *dev; + /* When tot_len isn't provided by user, check skb + * against MTU of FIB lookup resulting net_device + */ dev = dev_get_by_index_rcu(net, params->ifindex); if (!is_skb_forwardable(dev, skb)) rc = BPF_FIB_LKUP_RET_FRAG_NEEDED; + + params->mtu_result = dev->mtu; /* union with tot_len */ } return rc; @@ -5612,6 +5635,116 @@ static const struct bpf_func_proto bpf_skb_fib_lookup_proto = { .arg4_type = ARG_ANYTHING, }; +static struct net_device *__dev_via_ifindex(struct net_device *dev_curr, + u32 ifindex) +{ + struct net *netns = dev_net(dev_curr); + + /* Non-redirect use-cases can use ifindex=0 and save ifindex lookup */ + if (ifindex == 0) + return dev_curr; + + return dev_get_by_index_rcu(netns, ifindex); +} + +BPF_CALL_5(bpf_skb_check_mtu, struct sk_buff *, skb, + u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags) +{ + int ret = BPF_MTU_CHK_RET_FRAG_NEEDED; + struct net_device *dev = skb->dev; + int skb_len, dev_len; + int mtu; + + if (unlikely(flags & ~(BPF_MTU_CHK_SEGS))) + return -EINVAL; + + if (unlikely(flags & BPF_MTU_CHK_SEGS && len_diff)) + return -EINVAL; + + dev = __dev_via_ifindex(dev, ifindex); + if (unlikely(!dev)) + return -ENODEV; + + mtu = READ_ONCE(dev->mtu); + + dev_len = mtu + dev->hard_header_len; + skb_len = skb->len + len_diff; /* minus result pass check */ + if (skb_len <= dev_len) { + ret = BPF_MTU_CHK_RET_SUCCESS; + goto out; + } + /* At this point, skb->len exceed MTU, but as it include length of all + * segments, it can still be below MTU. The SKB can possibly get + * re-segmented in transmit path (see validate_xmit_skb). Thus, user + * must choose if segs are to be MTU checked. + */ + if (skb_is_gso(skb)) { + ret = BPF_MTU_CHK_RET_SUCCESS; + + if (flags & BPF_MTU_CHK_SEGS && + !skb_gso_validate_network_len(skb, mtu)) + ret = BPF_MTU_CHK_RET_SEGS_TOOBIG; + } +out: + /* BPF verifier guarantees valid pointer */ + *mtu_len = mtu; + + return ret; +} + +BPF_CALL_5(bpf_xdp_check_mtu, struct xdp_buff *, xdp, + u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags) +{ + struct net_device *dev = xdp->rxq->dev; + int xdp_len = xdp->data_end - xdp->data; + int ret = BPF_MTU_CHK_RET_SUCCESS; + int mtu, dev_len; + + /* XDP variant doesn't support multi-buffer segment check (yet) */ + if (unlikely(flags)) + return -EINVAL; + + dev = __dev_via_ifindex(dev, ifindex); + if (unlikely(!dev)) + return -ENODEV; + + mtu = READ_ONCE(dev->mtu); + + /* Add L2-header as dev MTU is L3 size */ + dev_len = mtu + dev->hard_header_len; + + xdp_len += len_diff; /* minus result pass check */ + if (xdp_len > dev_len) + ret = BPF_MTU_CHK_RET_FRAG_NEEDED; + + /* BPF verifier guarantees valid pointer */ + *mtu_len = mtu; + + return ret; +} + +static const struct bpf_func_proto bpf_skb_check_mtu_proto = { + .func = bpf_skb_check_mtu, + .gpl_only = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_PTR_TO_INT, + .arg4_type = ARG_ANYTHING, + .arg5_type = ARG_ANYTHING, +}; + +static const struct bpf_func_proto bpf_xdp_check_mtu_proto = { + .func = bpf_xdp_check_mtu, + .gpl_only = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_PTR_TO_INT, + .arg4_type = ARG_ANYTHING, + .arg5_type = ARG_ANYTHING, +}; + #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len) { @@ -7021,6 +7154,14 @@ sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_CGROUP_INET6_BIND: case BPF_CGROUP_INET4_CONNECT: case BPF_CGROUP_INET6_CONNECT: + case BPF_CGROUP_UDP4_RECVMSG: + case BPF_CGROUP_UDP6_RECVMSG: + case BPF_CGROUP_UDP4_SENDMSG: + case BPF_CGROUP_UDP6_SENDMSG: + case BPF_CGROUP_INET4_GETPEERNAME: + case BPF_CGROUP_INET6_GETPEERNAME: + case BPF_CGROUP_INET4_GETSOCKNAME: + case BPF_CGROUP_INET6_GETSOCKNAME: return &bpf_sock_addr_setsockopt_proto; default: return NULL; @@ -7031,6 +7172,14 @@ sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_CGROUP_INET6_BIND: case BPF_CGROUP_INET4_CONNECT: case BPF_CGROUP_INET6_CONNECT: + case BPF_CGROUP_UDP4_RECVMSG: + case BPF_CGROUP_UDP6_RECVMSG: + case BPF_CGROUP_UDP4_SENDMSG: + case BPF_CGROUP_UDP6_SENDMSG: + case BPF_CGROUP_INET4_GETPEERNAME: + case BPF_CGROUP_INET6_GETPEERNAME: + case BPF_CGROUP_INET4_GETSOCKNAME: + case BPF_CGROUP_INET6_GETSOCKNAME: return &bpf_sock_addr_getsockopt_proto; default: return NULL; @@ -7181,6 +7330,8 @@ tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_socket_uid_proto; case BPF_FUNC_fib_lookup: return &bpf_skb_fib_lookup_proto; + case BPF_FUNC_check_mtu: + return &bpf_skb_check_mtu_proto; case BPF_FUNC_sk_fullsock: return &bpf_sk_fullsock_proto; case BPF_FUNC_sk_storage_get: @@ -7250,6 +7401,8 @@ xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_xdp_adjust_tail_proto; case BPF_FUNC_fib_lookup: return &bpf_xdp_fib_lookup_proto; + case BPF_FUNC_check_mtu: + return &bpf_xdp_check_mtu_proto; #ifdef CONFIG_INET case BPF_FUNC_sk_lookup_udp: return &bpf_xdp_sk_lookup_udp_proto; |