Subject: [PATCH bpf-next 2/9] selftests/bpf: fix tests due to const spill/fill

From: Alexei Starovoitov <[email-masked]>
Date: Wed, 12 Jun 2019 21:19:56 -0700

fix tests that incorrectly assumed that the verifier
cannot track constants through stack.

Signed-off-by: Alexei Starovoitov <[email-masked]>
---
 .../bpf/verifier/direct_packet_access.c       |  3 +-
 .../bpf/verifier/helper_access_var_len.c      | 28 ++++++++++---------
 2 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/tools/testing/selftests/bpf/verifier/direct_packet_access.c b/tools/testing/selftests/bpf/verifier/direct_packet_access.c
index d5c596fdc4b9..2c5fbe7bcd27 100644
--- a/tools/testing/selftests/bpf/verifier/direct_packet_access.c
+++ b/tools/testing/selftests/bpf/verifier/direct_packet_access.c
@@ -511,7 +511,8 @@
 		    offsetof(struct __sk_buff, data)),
 	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
 		    offsetof(struct __sk_buff, data_end)),
-	BPF_MOV64_IMM(BPF_REG_0, 0xffffffff),
+	BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, mark)),
 	BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
 	BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 0xffff),
diff --git a/tools/testing/selftests/bpf/verifier/helper_access_var_len.c b/tools/testing/selftests/bpf/verifier/helper_access_var_len.c
index 1f39d845c64f..67ab12410050 100644
--- a/tools/testing/selftests/bpf/verifier/helper_access_var_len.c
+++ b/tools/testing/selftests/bpf/verifier/helper_access_var_len.c
@@ -29,9 +29,9 @@
 {
 	"helper access to variable memory: stack, bitwise AND, zero included",
 	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, 8),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -64),
-	BPF_MOV64_IMM(BPF_REG_2, 16),
 	BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_2, -128),
 	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, -128),
 	BPF_ALU64_IMM(BPF_AND, BPF_REG_2, 64),
@@ -46,9 +46,9 @@
 {
 	"helper access to variable memory: stack, bitwise AND + JMP, wrong max",
 	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, 8),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -64),
-	BPF_MOV64_IMM(BPF_REG_2, 16),
 	BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_2, -128),
 	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, -128),
 	BPF_ALU64_IMM(BPF_AND, BPF_REG_2, 65),
@@ -122,9 +122,9 @@
 {
 	"helper access to variable memory: stack, JMP, bounds + offset",
 	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, 8),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -64),
-	BPF_MOV64_IMM(BPF_REG_2, 16),
 	BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_2, -128),
 	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, -128),
 	BPF_JMP_IMM(BPF_JGT, BPF_REG_2, 64, 5),
@@ -143,9 +143,9 @@
 {
 	"helper access to variable memory: stack, JMP, wrong max",
 	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, 8),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -64),
-	BPF_MOV64_IMM(BPF_REG_2, 16),
 	BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_2, -128),
 	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, -128),
 	BPF_JMP_IMM(BPF_JGT, BPF_REG_2, 65, 4),
@@ -163,9 +163,9 @@
 {
 	"helper access to variable memory: stack, JMP, no max check",
 	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, 8),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -64),
-	BPF_MOV64_IMM(BPF_REG_2, 16),
 	BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_2, -128),
 	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, -128),
 	BPF_MOV64_IMM(BPF_REG_4, 0),
@@ -183,9 +183,9 @@
 {
 	"helper access to variable memory: stack, JMP, no min check",
 	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, 8),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -64),
-	BPF_MOV64_IMM(BPF_REG_2, 16),
 	BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_2, -128),
 	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, -128),
 	BPF_JMP_IMM(BPF_JGT, BPF_REG_2, 64, 3),
@@ -201,9 +201,9 @@
 {
 	"helper access to variable memory: stack, JMP (signed), no min check",
 	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, 8),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -64),
-	BPF_MOV64_IMM(BPF_REG_2, 16),
 	BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_2, -128),
 	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, -128),
 	BPF_JMP_IMM(BPF_JSGT, BPF_REG_2, 64, 3),
@@ -244,6 +244,7 @@
 {
 	"helper access to variable memory: map, JMP, wrong max",
 	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 8),
 	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
 	BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
@@ -251,7 +252,7 @@
 	BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
 	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 10),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
-	BPF_MOV64_IMM(BPF_REG_2, sizeof(struct test_val)),
+	BPF_MOV64_REG(BPF_REG_2, BPF_REG_6),
 	BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -128),
 	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_10, -128),
 	BPF_JMP_IMM(BPF_JSGT, BPF_REG_2, sizeof(struct test_val) + 1, 4),
@@ -262,7 +263,7 @@
 	BPF_MOV64_IMM(BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
-	.fixup_map_hash_48b = { 3 },
+	.fixup_map_hash_48b = { 4 },
 	.errstr = "invalid access to map value, value_size=48 off=0 size=49",
 	.result = REJECT,
 	.prog_type = BPF_PROG_TYPE_TRACEPOINT,
@@ -296,6 +297,7 @@
 {
 	"helper access to variable memory: map adjusted, JMP, wrong max",
 	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 8),
 	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
 	BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
@@ -304,7 +306,7 @@
 	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 11),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 20),
-	BPF_MOV64_IMM(BPF_REG_2, sizeof(struct test_val)),
+	BPF_MOV64_REG(BPF_REG_2, BPF_REG_6),
 	BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -128),
 	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_10, -128),
 	BPF_JMP_IMM(BPF_JSGT, BPF_REG_2, sizeof(struct test_val) - 19, 4),
@@ -315,7 +317,7 @@
 	BPF_MOV64_IMM(BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
-	.fixup_map_hash_48b = { 3 },
+	.fixup_map_hash_48b = { 4 },
 	.errstr = "R1 min value is outside of the array range",
 	.result = REJECT,
 	.prog_type = BPF_PROG_TYPE_TRACEPOINT,
@@ -337,8 +339,8 @@
 {
 	"helper access to variable memory: size > 0 not allowed on NULL (ARG_PTR_TO_MEM_OR_NULL)",
 	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 0),
 	BPF_MOV64_IMM(BPF_REG_1, 0),
-	BPF_MOV64_IMM(BPF_REG_2, 1),
 	BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -128),
 	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_10, -128),
 	BPF_ALU64_IMM(BPF_AND, BPF_REG_2, 64),
@@ -562,6 +564,7 @@
 {
 	"helper access to variable memory: 8 bytes leak",
 	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, 8),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -64),
 	BPF_MOV64_IMM(BPF_REG_0, 0),
@@ -572,7 +575,6 @@
 	BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -24),
 	BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16),
 	BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
-	BPF_MOV64_IMM(BPF_REG_2, 1),
 	BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -128),
 	BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_10, -128),
 	BPF_ALU64_IMM(BPF_AND, BPF_REG_2, 63),
-- 
2.20.0