From: Yonghong Song <yhs@fb.com>
Date: Sat, 28 Apr 2018 22:28:14 -0700
Subject: tools/bpf: add a verifier test case for bpf_get_stack helper and ARSH
Patch-mainline: v4.18-rc1
Git-commit: 2abe611c5f031f06ab783102e62c0ae9dfd93e80
References: bsc#1109837

The test_verifier already has a few ARSH test cases.
This patch adds a new test case which takes advantage of newly
improved verifier behavior for bpf_get_stack and ARSH.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 tools/testing/selftests/bpf/test_verifier.c |   46 +++++++++++++++++++++++++++-
 1 file changed, 45 insertions(+), 1 deletion(-)

--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -11593,6 +11593,51 @@ static struct bpf_test tests[] = {
 		.prog_type = BPF_PROG_TYPE_XDP,
 	},
 	{
+		"bpf_get_stack return R0 within range",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+				     BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 28),
+			BPF_MOV64_REG(BPF_REG_7, BPF_REG_0),
+			BPF_MOV64_IMM(BPF_REG_9, sizeof(struct test_val)),
+			BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_7),
+			BPF_MOV64_IMM(BPF_REG_3, sizeof(struct test_val)),
+			BPF_MOV64_IMM(BPF_REG_4, 256),
+			BPF_EMIT_CALL(BPF_FUNC_get_stack),
+			BPF_MOV64_IMM(BPF_REG_1, 0),
+			BPF_MOV64_REG(BPF_REG_8, BPF_REG_0),
+			BPF_ALU64_IMM(BPF_LSH, BPF_REG_8, 32),
+			BPF_ALU64_IMM(BPF_ARSH, BPF_REG_8, 32),
+			BPF_JMP_REG(BPF_JSLT, BPF_REG_1, BPF_REG_8, 16),
+			BPF_ALU64_REG(BPF_SUB, BPF_REG_9, BPF_REG_8),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_7),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_8),
+			BPF_MOV64_REG(BPF_REG_1, BPF_REG_9),
+			BPF_ALU64_IMM(BPF_LSH, BPF_REG_1, 32),
+			BPF_ALU64_IMM(BPF_ARSH, BPF_REG_1, 32),
+			BPF_MOV64_REG(BPF_REG_3, BPF_REG_2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_3, BPF_REG_1),
+			BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
+			BPF_MOV64_IMM(BPF_REG_5, sizeof(struct test_val)),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_5),
+			BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_1, 4),
+			BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
+			BPF_MOV64_REG(BPF_REG_3, BPF_REG_9),
+			BPF_MOV64_IMM(BPF_REG_4, 0),
+			BPF_EMIT_CALL(BPF_FUNC_get_stack),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map2 = { 4 },
+		.result = ACCEPT,
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
 		"jit: lsh, rsh, arsh by 1",
 		.insns = {
 			BPF_MOV64_IMM(BPF_REG_0, 1),
@@ -11680,7 +11725,6 @@ static struct bpf_test tests[] = {
 		.result = ACCEPT,
 		.retval = 2,
 	},
-
 };
 
 static int probe_filter_length(const struct bpf_insn *fp)