[PATCH disco 2/3] bpf: add various test cases to selftests

[Thadeu Lima de Souza Cascardo]

From: Daniel Borkmann <daniel at iogearbox.net>

Add various map value pointer related test cases to test_verifier
kselftest to reflect recent changes and improve test coverage. The
tests include basic masking functionality, unprivileged behavior
on pointer arithmetic which goes oob, mixed bounds tests, negative
unknown scalar but resulting positive offset for access and helper
range, handling of arithmetic from multiple maps, various masking
scenarios with subsequent map value access and others including two
test cases from Jann Horn for prior fixes.

Signed-off-by: Daniel Borkmann <daniel at iogearbox.net>
Acked-by: Alexei Starovoitov <ast at kernel.org>
Signed-off-by: Alexei Starovoitov <ast at kernel.org>
(backported from 80c9b2fae87bb5c5698940da1a981f14f89518d1)
[cascardo: really picked only the few changes we needed to make test work again]
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo at canonical.com>
---
 tools/testing/selftests/bpf/test_verifier.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index d9adb492c2c8..e6c41217c7fa 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -2476,6 +2476,7 @@ static struct bpf_test tests[] = {
 		},
 		.result = REJECT,
 		.errstr = "invalid stack off=-79992 size=8",
+		.errstr_unpriv = "R1 stack pointer arithmetic goes out of range",
 	},
 	{
 		"PTR_TO_STACK store/load - out of bounds high",
@@ -2872,6 +2873,8 @@ static struct bpf_test tests[] = {
 			BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, -8),
 			BPF_EXIT_INSN(),
 		},
+		.errstr_unpriv = "R1 stack pointer arithmetic goes out of range",
+		.result_unpriv = REJECT,
 		.result = ACCEPT,
 	},
 	{
@@ -7485,6 +7488,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "unbounded min value",
+		.errstr_unpriv = "R1 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 	},
 	{
@@ -7509,6 +7513,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "unbounded min value",
+		.errstr_unpriv = "R1 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 	},
 	{
@@ -7535,6 +7540,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "unbounded min value",
+		.errstr_unpriv = "R8 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 	},
 	{
@@ -7560,6 +7566,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "unbounded min value",
+		.errstr_unpriv = "R8 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 	},
 	{
@@ -7608,6 +7615,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "unbounded min value",
+		.errstr_unpriv = "R1 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 	},
 	{
@@ -7679,6 +7687,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "unbounded min value",
+		.errstr_unpriv = "R1 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 	},
 	{
@@ -7730,6 +7739,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "unbounded min value",
+		.errstr_unpriv = "R1 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 	},
 	{
@@ -7757,6 +7767,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "unbounded min value",
+		.errstr_unpriv = "R1 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 	},
 	{
@@ -7783,6 +7794,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "unbounded min value",
+		.errstr_unpriv = "R1 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 	},
 	{
@@ -7812,6 +7824,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "unbounded min value",
+		.errstr_unpriv = "R7 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 	},
 	{
@@ -7842,6 +7855,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 4 },
 		.errstr = "R0 invalid mem access 'inv'",
+		.errstr_unpriv = "R1 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 	},
 	{
@@ -7870,6 +7884,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "unbounded min value",
+		.errstr_unpriv = "R1 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 		.result_unpriv = REJECT,
 	},
@@ -7922,6 +7937,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
+		.errstr_unpriv = "R1 has unknown scalar with mixed signed bounds",
 		.result = REJECT,
 	},
 	{
@@ -8294,6 +8310,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "pointer offset 1073741822",
+		.errstr_unpriv = "R0 pointer arithmetic of map value goes out of range",
 		.result = REJECT
 	},
 	{
@@ -8315,6 +8332,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup_map1 = { 3 },
 		.errstr = "pointer offset -1073741822",
+		.errstr_unpriv = "R0 pointer arithmetic of map value goes out of range",
 		.result = REJECT
 	},
 	{
@@ -8486,6 +8504,7 @@ static struct bpf_test tests[] = {
 			BPF_EXIT_INSN()
 		},
 		.errstr = "fp pointer offset 1073741822",
+		.errstr_unpriv = "R1 stack pointer arithmetic goes out of range",
 		.result = REJECT
 	},
 	{
-- 
2.20.1