arm64: bpf: implement jitting of JMP32

mainline inclusion
from mainline-v5.1-rc1
commit 654b65a04880454efb7d3287f011f2f790963b32
category: bugfix
bugzilla: NA
CVE: CVE-2021-3444

--------------------------------

This patch implements code-gen for new JMP32 instructions on arm64.

Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Zi Shen Lim <zlim.lnx@gmail.com>
Signed-off-by: NJiong Wang <jiong.wang@netronome.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Conflicts:
  arch/arm64/net/bpf_jit_comp.c

Signed-off-by: He Fengqing<hefengqing@huawei.com>
Reviewed-by: NKuohai Xu <xukuohai@huawei.com>
Reviewed-by: NXiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: NYu Changchun <yuchangchun1@huawei.com>

arch/arm64/net/bpf_jit_comp.c

@@ -362,7 +362,8 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
 	const s16 off = insn->off;
 	const s32 imm = insn->imm;
 	const int i = insn - ctx->prog->insnsi;
-	const bool is64 = BPF_CLASS(code) == BPF_ALU64;
+	const bool is64 = BPF_CLASS(code) == BPF_ALU64 ||
+			  BPF_CLASS(code) == BPF_JMP;
 	const bool isdw = BPF_SIZE(code) == BPF_DW;
 	u8 jmp_cond, reg;
 	s32 jmp_offset;
@@ -559,7 +560,17 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
 	case BPF_JMP | BPF_JSLT | BPF_X:
 	case BPF_JMP | BPF_JSGE | BPF_X:
 	case BPF_JMP | BPF_JSLE | BPF_X:
-		emit(A64_CMP(1, dst, src), ctx);
+	case BPF_JMP32 | BPF_JEQ | BPF_X:
+	case BPF_JMP32 | BPF_JGT | BPF_X:
+	case BPF_JMP32 | BPF_JLT | BPF_X:
+	case BPF_JMP32 | BPF_JGE | BPF_X:
+	case BPF_JMP32 | BPF_JLE | BPF_X:
+	case BPF_JMP32 | BPF_JNE | BPF_X:
+	case BPF_JMP32 | BPF_JSGT | BPF_X:
+	case BPF_JMP32 | BPF_JSLT | BPF_X:
+	case BPF_JMP32 | BPF_JSGE | BPF_X:
+	case BPF_JMP32 | BPF_JSLE | BPF_X:
+		emit(A64_CMP(is64, dst, src), ctx);
 emit_cond_jmp:
 		jmp_offset = bpf2a64_offset(i + off, i, ctx);
 		check_imm19(jmp_offset);
@@ -601,7 +612,8 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
 		emit(A64_B_(jmp_cond, jmp_offset), ctx);
 		break;
 	case BPF_JMP | BPF_JSET | BPF_X:
-		emit(A64_TST(1, dst, src), ctx);
+	case BPF_JMP32 | BPF_JSET | BPF_X:
+		emit(A64_TST(is64, dst, src), ctx);
 		goto emit_cond_jmp;
 	/* IF (dst COND imm) JUMP off */
 	case BPF_JMP | BPF_JEQ | BPF_K:
@@ -614,12 +626,23 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
 	case BPF_JMP | BPF_JSLT | BPF_K:
 	case BPF_JMP | BPF_JSGE | BPF_K:
 	case BPF_JMP | BPF_JSLE | BPF_K:
-		emit_a64_mov_i(1, tmp, imm, ctx);
-		emit(A64_CMP(1, dst, tmp), ctx);
+	case BPF_JMP32 | BPF_JEQ | BPF_K:
+	case BPF_JMP32 | BPF_JGT | BPF_K:
+	case BPF_JMP32 | BPF_JLT | BPF_K:
+	case BPF_JMP32 | BPF_JGE | BPF_K:
+	case BPF_JMP32 | BPF_JLE | BPF_K:
+	case BPF_JMP32 | BPF_JNE | BPF_K:
+	case BPF_JMP32 | BPF_JSGT | BPF_K:
+	case BPF_JMP32 | BPF_JSLT | BPF_K:
+	case BPF_JMP32 | BPF_JSGE | BPF_K:
+	case BPF_JMP32 | BPF_JSLE | BPF_K:
+		emit_a64_mov_i(is64, tmp, imm, ctx);
+		emit(A64_CMP(is64, dst, tmp), ctx);
 		goto emit_cond_jmp;
 	case BPF_JMP | BPF_JSET | BPF_K:
-		emit_a64_mov_i(1, tmp, imm, ctx);
-		emit(A64_TST(1, dst, tmp), ctx);
+	case BPF_JMP32 | BPF_JSET | BPF_K:
+		emit_a64_mov_i(is64, tmp, imm, ctx);
+		emit(A64_TST(is64, dst, tmp), ctx);
 		goto emit_cond_jmp;
 	/* function call */
 	case BPF_JMP | BPF_CALL: