net/bpf: split VLAN_PRESENT bit handling from VLAN_TCI (9c212255) · Commits · 戴 / test

net/core/filter.c

+21 −19

Original line number	Diff line number	Diff line
		@@ -296,22 +296,21 @@ static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
		break;

		case SKF_AD_VLAN_TAG:
		case SKF_AD_VLAN_TAG_PRESENT:
		BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
		BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);

		/* dst_reg = (u16 ) (src_reg + offsetof(vlan_tci)) */
		*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
		offsetof(struct sk_buff, vlan_tci));
		if (skb_field == SKF_AD_VLAN_TAG) {
		*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg,
		~VLAN_TAG_PRESENT);
		} else {
		/* dst_reg >>= 12 */
		*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 12);
		/* dst_reg &= 1 */
		#ifdef VLAN_TAG_PRESENT
		*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, ~VLAN_TAG_PRESENT);
		#endif
		break;
		case SKF_AD_VLAN_TAG_PRESENT:
		*insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_VLAN_PRESENT_OFFSET());
		if (PKT_VLAN_PRESENT_BIT)
		*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, PKT_VLAN_PRESENT_BIT);
		if (PKT_VLAN_PRESENT_BIT < 7)
		*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1);
		}
		break;
		}

		@@ -6140,19 +6139,22 @@ static u32 bpf_convert_ctx_access(enum bpf_access_type type,
		break;

		case offsetof(struct __sk_buff, vlan_present):
		case offsetof(struct __sk_buff, vlan_tci):
		BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
		*target_size = 1;
		*insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
		PKT_VLAN_PRESENT_OFFSET());
		if (PKT_VLAN_PRESENT_BIT)
		*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, PKT_VLAN_PRESENT_BIT);
		if (PKT_VLAN_PRESENT_BIT < 7)
		*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
		break;

		case offsetof(struct __sk_buff, vlan_tci):
		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
		bpf_target_off(struct sk_buff, vlan_tci, 2,
		target_size));
		if (si->off == offsetof(struct __sk_buff, vlan_tci)) {
		*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg,
		~VLAN_TAG_PRESENT);
		} else {
		*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 12);
		*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
		}
		#ifdef VLAN_TAG_PRESENT
		*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, ~VLAN_TAG_PRESENT);
		#endif
		break;

		case offsetof(struct __sk_buff, cb[0]) ...

Admin message