test: bpf: add a testcase reduced from nmap

nmap generates classic BPF programs to filter ARP packets with given target MAC
which triggered a bug in eBPF x64 JIT. The bug was fixed in
commit e0ee9c1215 ("x86: bpf_jit: fix two bugs in eBPF JIT compiler")
This patch is adding a testcase in eBPF instructions (those that
were generated by classic->eBPF converter) to be processed by JIT.
The test is primarily targeting JIT compiler.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

lib/test_bpf.c

@@ -1756,6 +1756,49 @@ static struct bpf_test tests[] = {
 		{ },
 		{ { 0, 1 } }
 	},
+	{
+		"nmap reduced",
+		.u.insns_int = {
+			BPF_MOV64_REG(R6, R1),
+			BPF_LD_ABS(BPF_H, 12),
+			BPF_JMP_IMM(BPF_JNE, R0, 0x806, 28),
+			BPF_LD_ABS(BPF_H, 12),
+			BPF_JMP_IMM(BPF_JNE, R0, 0x806, 26),
+			BPF_MOV32_IMM(R0, 18),
+			BPF_STX_MEM(BPF_W, R10, R0, -64),
+			BPF_LDX_MEM(BPF_W, R7, R10, -64),
+			BPF_LD_IND(BPF_W, R7, 14),
+			BPF_STX_MEM(BPF_W, R10, R0, -60),
+			BPF_MOV32_IMM(R0, 280971478),
+			BPF_STX_MEM(BPF_W, R10, R0, -56),
+			BPF_LDX_MEM(BPF_W, R7, R10, -56),
+			BPF_LDX_MEM(BPF_W, R0, R10, -60),
+			BPF_ALU32_REG(BPF_SUB, R0, R7),
+			BPF_JMP_IMM(BPF_JNE, R0, 0, 15),
+			BPF_LD_ABS(BPF_H, 12),
+			BPF_JMP_IMM(BPF_JNE, R0, 0x806, 13),
+			BPF_MOV32_IMM(R0, 22),
+			BPF_STX_MEM(BPF_W, R10, R0, -56),
+			BPF_LDX_MEM(BPF_W, R7, R10, -56),
+			BPF_LD_IND(BPF_H, R7, 14),
+			BPF_STX_MEM(BPF_W, R10, R0, -52),
+			BPF_MOV32_IMM(R0, 17366),
+			BPF_STX_MEM(BPF_W, R10, R0, -48),
+			BPF_LDX_MEM(BPF_W, R7, R10, -48),
+			BPF_LDX_MEM(BPF_W, R0, R10, -52),
+			BPF_ALU32_REG(BPF_SUB, R0, R7),
+			BPF_JMP_IMM(BPF_JNE, R0, 0, 2),
+			BPF_MOV32_IMM(R0, 256),
+			BPF_EXIT_INSN(),
+			BPF_MOV32_IMM(R0, 0),
+			BPF_EXIT_INSN(),
+		},
+		INTERNAL,
+		{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0x06, 0, 0,
+		  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+		  0x10, 0xbf, 0x48, 0xd6, 0x43, 0xd6},
+		{ { 38, 256 } }
+	},
 };
 
 static struct net_device dev;