diff options
| -rw-r--r-- | net/core/filter.c | 26 | ||||
| -rw-r--r-- | net/sched/act_bpf.c | 9 | ||||
| -rw-r--r-- | net/sched/cls_bpf.c | 16 | ||||
| -rw-r--r-- | samples/bpf/tcbpf1_kern.c | 8 |
4 files changed, 30 insertions, 29 deletions
diff --git a/net/core/filter.c b/net/core/filter.c index 09b2062eb5b8..36a69e33d76b 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -1238,21 +1238,6 @@ int sk_attach_bpf(u32 ufd, struct sock *sk) return 0; } -/** - * bpf_skb_clone_not_writable - is the header of a clone not writable - * @skb: buffer to check - * @len: length up to which to write, can be negative - * - * Returns true if modifying the header part of the cloned buffer - * does require the data to be copied. I.e. this version works with - * negative lengths needed for eBPF case! - */ -static bool bpf_skb_clone_unwritable(const struct sk_buff *skb, int len) -{ - return skb_header_cloned(skb) || - (int) skb_headroom(skb) + len > skb->hdr_len; -} - #define BPF_RECOMPUTE_CSUM(flags) ((flags) & 1) static u64 bpf_skb_store_bytes(u64 r1, u64 r2, u64 r3, u64 r4, u64 flags) @@ -1275,9 +1260,8 @@ static u64 bpf_skb_store_bytes(u64 r1, u64 r2, u64 r3, u64 r4, u64 flags) if (unlikely((u32) offset > 0xffff || len > sizeof(buf))) return -EFAULT; - offset -= skb->data - skb_mac_header(skb); if (unlikely(skb_cloned(skb) && - bpf_skb_clone_unwritable(skb, offset + len))) + !skb_clone_writable(skb, offset + len))) return -EFAULT; ptr = skb_header_pointer(skb, offset, len, buf); @@ -1321,9 +1305,8 @@ static u64 bpf_l3_csum_replace(u64 r1, u64 r2, u64 from, u64 to, u64 flags) if (unlikely((u32) offset > 0xffff)) return -EFAULT; - offset -= skb->data - skb_mac_header(skb); if (unlikely(skb_cloned(skb) && - bpf_skb_clone_unwritable(skb, offset + sizeof(sum)))) + !skb_clone_writable(skb, offset + sizeof(sum)))) return -EFAULT; ptr = skb_header_pointer(skb, offset, sizeof(sum), &sum); @@ -1369,9 +1352,8 @@ static u64 bpf_l4_csum_replace(u64 r1, u64 r2, u64 from, u64 to, u64 flags) if (unlikely((u32) offset > 0xffff)) return -EFAULT; - offset -= skb->data - skb_mac_header(skb); if (unlikely(skb_cloned(skb) && - bpf_skb_clone_unwritable(skb, offset + sizeof(sum)))) + !skb_clone_writable(skb, offset + sizeof(sum)))) return -EFAULT; ptr = skb_header_pointer(skb, offset, sizeof(sum), &sum); @@ -1425,8 +1407,6 @@ static u64 bpf_clone_redirect(u64 r1, u64 ifindex, u64 flags, u64 r4, u64 r5) if (unlikely(!skb2)) return -ENOMEM; - skb_push(skb2, skb2->data - skb_mac_header(skb2)); - if (BPF_IS_REDIRECT_INGRESS(flags)) return dev_forward_skb(dev, skb2); diff --git a/net/sched/act_bpf.c b/net/sched/act_bpf.c index dc6a2d324bd8..1d56903fd4c7 100644 --- a/net/sched/act_bpf.c +++ b/net/sched/act_bpf.c @@ -37,6 +37,7 @@ static int tcf_bpf(struct sk_buff *skb, const struct tc_action *act, { struct tcf_bpf *prog = act->priv; int action, filter_res; + bool at_ingress = G_TC_AT(skb->tc_verd) & AT_INGRESS; if (unlikely(!skb_mac_header_was_set(skb))) return TC_ACT_UNSPEC; @@ -48,7 +49,13 @@ static int tcf_bpf(struct sk_buff *skb, const struct tc_action *act, /* Needed here for accessing maps. */ rcu_read_lock(); - filter_res = BPF_PROG_RUN(prog->filter, skb); + if (at_ingress) { + __skb_push(skb, skb->mac_len); + filter_res = BPF_PROG_RUN(prog->filter, skb); + __skb_pull(skb, skb->mac_len); + } else { + filter_res = BPF_PROG_RUN(prog->filter, skb); + } rcu_read_unlock(); /* A BPF program may overwrite the default action opcode. diff --git a/net/sched/cls_bpf.c b/net/sched/cls_bpf.c index 91bd9c19471d..c79ecfd36e0f 100644 --- a/net/sched/cls_bpf.c +++ b/net/sched/cls_bpf.c @@ -64,6 +64,11 @@ static int cls_bpf_classify(struct sk_buff *skb, const struct tcf_proto *tp, { struct cls_bpf_head *head = rcu_dereference_bh(tp->root); struct cls_bpf_prog *prog; +#ifdef CONFIG_NET_CLS_ACT + bool at_ingress = G_TC_AT(skb->tc_verd) & AT_INGRESS; +#else + bool at_ingress = false; +#endif int ret = -1; if (unlikely(!skb_mac_header_was_set(skb))) @@ -72,7 +77,16 @@ static int cls_bpf_classify(struct sk_buff *skb, const struct tcf_proto *tp, /* Needed here for accessing maps. */ rcu_read_lock(); list_for_each_entry_rcu(prog, &head->plist, link) { - int filter_res = BPF_PROG_RUN(prog->filter, skb); + int filter_res; + + if (at_ingress) { + /* It is safe to push/pull even if skb_shared() */ + __skb_push(skb, skb->mac_len); + filter_res = BPF_PROG_RUN(prog->filter, skb); + __skb_pull(skb, skb->mac_len); + } else { + filter_res = BPF_PROG_RUN(prog->filter, skb); + } if (filter_res == 0) continue; diff --git a/samples/bpf/tcbpf1_kern.c b/samples/bpf/tcbpf1_kern.c index 7c27710f8296..9bfb2eb34563 100644 --- a/samples/bpf/tcbpf1_kern.c +++ b/samples/bpf/tcbpf1_kern.c @@ -21,7 +21,7 @@ static inline void set_dst_mac(struct __sk_buff *skb, char *mac) static inline void set_ip_tos(struct __sk_buff *skb, __u8 new_tos) { - __u8 old_tos = load_byte(skb, BPF_LL_OFF + TOS_OFF); + __u8 old_tos = load_byte(skb, TOS_OFF); bpf_l3_csum_replace(skb, IP_CSUM_OFF, htons(old_tos), htons(new_tos), 2); bpf_skb_store_bytes(skb, TOS_OFF, &new_tos, sizeof(new_tos), 0); @@ -34,7 +34,7 @@ static inline void set_ip_tos(struct __sk_buff *skb, __u8 new_tos) static inline void set_tcp_ip_src(struct __sk_buff *skb, __u32 new_ip) { - __u32 old_ip = _htonl(load_word(skb, BPF_LL_OFF + IP_SRC_OFF)); + __u32 old_ip = _htonl(load_word(skb, IP_SRC_OFF)); bpf_l4_csum_replace(skb, TCP_CSUM_OFF, old_ip, new_ip, IS_PSEUDO | sizeof(new_ip)); bpf_l3_csum_replace(skb, IP_CSUM_OFF, old_ip, new_ip, sizeof(new_ip)); @@ -44,7 +44,7 @@ static inline void set_tcp_ip_src(struct __sk_buff *skb, __u32 new_ip) #define TCP_DPORT_OFF (ETH_HLEN + sizeof(struct iphdr) + offsetof(struct tcphdr, dest)) static inline void set_tcp_dest_port(struct __sk_buff *skb, __u16 new_port) { - __u16 old_port = htons(load_half(skb, BPF_LL_OFF + TCP_DPORT_OFF)); + __u16 old_port = htons(load_half(skb, TCP_DPORT_OFF)); bpf_l4_csum_replace(skb, TCP_CSUM_OFF, old_port, new_port, sizeof(new_port)); bpf_skb_store_bytes(skb, TCP_DPORT_OFF, &new_port, sizeof(new_port), 0); @@ -53,7 +53,7 @@ static inline void set_tcp_dest_port(struct __sk_buff *skb, __u16 new_port) SEC("classifier") int bpf_prog1(struct __sk_buff *skb) { - __u8 proto = load_byte(skb, BPF_LL_OFF + ETH_HLEN + offsetof(struct iphdr, protocol)); + __u8 proto = load_byte(skb, ETH_HLEN + offsetof(struct iphdr, protocol)); long *value; if (proto == IPPROTO_TCP) { |