diff mbox series

[SRU,Bionic,3/4] bpf: add further test cases around div/mod and others

Message ID 20211029203624.1367572-4-cascardo@canonical.com
State New
Headers show
Series BPF tests on i386 | expand

Commit Message

Thadeu Lima de Souza Cascardo Oct. 29, 2021, 8:36 p.m. UTC 
From: Daniel Borkmann <daniel@iogearbox.net>

BugLink: https://bugs.launchpad.net/bugs/1934414

Update selftests to relfect recent changes and add various new
test cases.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
(backported from commit 21ccaf21497b72f42133182716a42dbf573d314b)
[cascardo: Fixed conflict around header as limits.h was already included]
[cascardo: omitted hunks that add 3 call tests, that would require commit
 cc8b0b92a1699bc32f7fec71daa2bfc90de43a4d ("bpf: introduce function calls (function boundaries)")]
[cascardo: omitted the changes to "unknown opcode XX", this requires
 commit 5e581dad4fec0e6d062740dc35b8dc248b39d224]
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
---
 lib/test_bpf.c                              |   8 +-
 tools/testing/selftests/bpf/test_verifier.c | 242 +++++++++++++++++++-
 2 files changed, 243 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index 49da3625032f..d89d9d8da469 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -2004,10 +2004,14 @@  static struct bpf_test tests[] = {
 		{ { 4, 0 }, { 5, 10 } }
 	},
 	{
-		"INT: DIV by zero",
+		/* This one doesn't go through verifier, but is just raw insn
+		 * as opposed to cBPF tests from here. Thus div by 0 tests are
+		 * done in test_verifier in BPF kselftests.
+		 */
+		"INT: DIV by -1",
 		.u.insns_int = {
 			BPF_ALU64_REG(BPF_MOV, R6, R1),
-			BPF_ALU64_IMM(BPF_MOV, R7, 0),
+			BPF_ALU64_IMM(BPF_MOV, R7, -1),
 			BPF_LD_ABS(BPF_B, 3),
 			BPF_ALU32_REG(BPF_DIV, R0, R7),
 			BPF_EXIT_INSN(),
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 7f28618de35e..f3cf249030e6 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -112,7 +112,7 @@  static struct bpf_test tests[] = {
 			BPF_EXIT_INSN(),
 		},
 		.result = ACCEPT,
-		.retval = 0,
+		.retval = 42,
 	},
 	{
 		"DIV32 by 0, zero check 2",
@@ -124,7 +124,7 @@  static struct bpf_test tests[] = {
 			BPF_EXIT_INSN(),
 		},
 		.result = ACCEPT,
-		.retval = 0,
+		.retval = 42,
 	},
 	{
 		"DIV64 by 0, zero check",
@@ -136,7 +136,7 @@  static struct bpf_test tests[] = {
 			BPF_EXIT_INSN(),
 		},
 		.result = ACCEPT,
-		.retval = 0,
+		.retval = 42,
 	},
 	{
 		"MOD32 by 0, zero check 1",
@@ -148,7 +148,7 @@  static struct bpf_test tests[] = {
 			BPF_EXIT_INSN(),
 		},
 		.result = ACCEPT,
-		.retval = 0,
+		.retval = 42,
 	},
 	{
 		"MOD32 by 0, zero check 2",
@@ -160,7 +160,7 @@  static struct bpf_test tests[] = {
 			BPF_EXIT_INSN(),
 		},
 		.result = ACCEPT,
-		.retval = 0,
+		.retval = 42,
 	},
 	{
 		"MOD64 by 0, zero check",
@@ -172,8 +172,240 @@  static struct bpf_test tests[] = {
 			BPF_EXIT_INSN(),
 		},
 		.result = ACCEPT,
+		.retval = 42,
+	},
+	{
+		"DIV32 by 0, zero check ok, cls",
+		.insns = {
+			BPF_MOV32_IMM(BPF_REG_0, 42),
+			BPF_MOV32_IMM(BPF_REG_1, 2),
+			BPF_MOV32_IMM(BPF_REG_2, 16),
+			BPF_ALU32_REG(BPF_DIV, BPF_REG_2, BPF_REG_1),
+			BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 8,
+	},
+	{
+		"DIV32 by 0, zero check 1, cls",
+		.insns = {
+			BPF_MOV32_IMM(BPF_REG_1, 0),
+			BPF_MOV32_IMM(BPF_REG_0, 1),
+			BPF_ALU32_REG(BPF_DIV, BPF_REG_0, BPF_REG_1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 0,
+	},
+	{
+		"DIV32 by 0, zero check 2, cls",
+		.insns = {
+			BPF_LD_IMM64(BPF_REG_1, 0xffffffff00000000LL),
+			BPF_MOV32_IMM(BPF_REG_0, 1),
+			BPF_ALU32_REG(BPF_DIV, BPF_REG_0, BPF_REG_1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
 		.retval = 0,
 	},
+	{
+		"DIV64 by 0, zero check, cls",
+		.insns = {
+			BPF_MOV32_IMM(BPF_REG_1, 0),
+			BPF_MOV32_IMM(BPF_REG_0, 1),
+			BPF_ALU64_REG(BPF_DIV, BPF_REG_0, BPF_REG_1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 0,
+	},
+	{
+		"MOD32 by 0, zero check ok, cls",
+		.insns = {
+			BPF_MOV32_IMM(BPF_REG_0, 42),
+			BPF_MOV32_IMM(BPF_REG_1, 3),
+			BPF_MOV32_IMM(BPF_REG_2, 5),
+			BPF_ALU32_REG(BPF_MOD, BPF_REG_2, BPF_REG_1),
+			BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 2,
+	},
+	{
+		"MOD32 by 0, zero check 1, cls",
+		.insns = {
+			BPF_MOV32_IMM(BPF_REG_1, 0),
+			BPF_MOV32_IMM(BPF_REG_0, 1),
+			BPF_ALU32_REG(BPF_MOD, BPF_REG_0, BPF_REG_1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 1,
+	},
+	{
+		"MOD32 by 0, zero check 2, cls",
+		.insns = {
+			BPF_LD_IMM64(BPF_REG_1, 0xffffffff00000000LL),
+			BPF_MOV32_IMM(BPF_REG_0, 1),
+			BPF_ALU32_REG(BPF_MOD, BPF_REG_0, BPF_REG_1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 1,
+	},
+	{
+		"MOD64 by 0, zero check 1, cls",
+		.insns = {
+			BPF_MOV32_IMM(BPF_REG_1, 0),
+			BPF_MOV32_IMM(BPF_REG_0, 2),
+			BPF_ALU64_REG(BPF_MOD, BPF_REG_0, BPF_REG_1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 2,
+	},
+	{
+		"MOD64 by 0, zero check 2, cls",
+		.insns = {
+			BPF_MOV32_IMM(BPF_REG_1, 0),
+			BPF_MOV32_IMM(BPF_REG_0, -1),
+			BPF_ALU64_REG(BPF_MOD, BPF_REG_0, BPF_REG_1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = -1,
+	},
+	/* Just make sure that JITs used udiv/umod as otherwise we get
+	 * an exception from INT_MIN/-1 overflow similarly as with div
+	 * by zero.
+	 */
+	{
+		"DIV32 overflow, check 1",
+		.insns = {
+			BPF_MOV32_IMM(BPF_REG_1, -1),
+			BPF_MOV32_IMM(BPF_REG_0, INT_MIN),
+			BPF_ALU32_REG(BPF_DIV, BPF_REG_0, BPF_REG_1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 0,
+	},
+	{
+		"DIV32 overflow, check 2",
+		.insns = {
+			BPF_MOV32_IMM(BPF_REG_0, INT_MIN),
+			BPF_ALU32_IMM(BPF_DIV, BPF_REG_0, -1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 0,
+	},
+	{
+		"DIV64 overflow, check 1",
+		.insns = {
+			BPF_MOV64_IMM(BPF_REG_1, -1),
+			BPF_LD_IMM64(BPF_REG_0, LLONG_MIN),
+			BPF_ALU64_REG(BPF_DIV, BPF_REG_0, BPF_REG_1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 0,
+	},
+	{
+		"DIV64 overflow, check 2",
+		.insns = {
+			BPF_LD_IMM64(BPF_REG_0, LLONG_MIN),
+			BPF_ALU64_IMM(BPF_DIV, BPF_REG_0, -1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 0,
+	},
+	{
+		"MOD32 overflow, check 1",
+		.insns = {
+			BPF_MOV32_IMM(BPF_REG_1, -1),
+			BPF_MOV32_IMM(BPF_REG_0, INT_MIN),
+			BPF_ALU32_REG(BPF_MOD, BPF_REG_0, BPF_REG_1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = INT_MIN,
+	},
+	{
+		"MOD32 overflow, check 2",
+		.insns = {
+			BPF_MOV32_IMM(BPF_REG_0, INT_MIN),
+			BPF_ALU32_IMM(BPF_MOD, BPF_REG_0, -1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = INT_MIN,
+	},
+	{
+		"MOD64 overflow, check 1",
+		.insns = {
+			BPF_MOV64_IMM(BPF_REG_1, -1),
+			BPF_LD_IMM64(BPF_REG_2, LLONG_MIN),
+			BPF_MOV64_REG(BPF_REG_3, BPF_REG_2),
+			BPF_ALU64_REG(BPF_MOD, BPF_REG_2, BPF_REG_1),
+			BPF_MOV32_IMM(BPF_REG_0, 0),
+			BPF_JMP_REG(BPF_JNE, BPF_REG_3, BPF_REG_2, 1),
+			BPF_MOV32_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 1,
+	},
+	{
+		"MOD64 overflow, check 2",
+		.insns = {
+			BPF_LD_IMM64(BPF_REG_2, LLONG_MIN),
+			BPF_MOV64_REG(BPF_REG_3, BPF_REG_2),
+			BPF_ALU64_IMM(BPF_MOD, BPF_REG_2, -1),
+			BPF_MOV32_IMM(BPF_REG_0, 0),
+			BPF_JMP_REG(BPF_JNE, BPF_REG_3, BPF_REG_2, 1),
+			BPF_MOV32_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 1,
+	},
+	{
+		"xor32 zero extend check",
+		.insns = {
+			BPF_MOV32_IMM(BPF_REG_2, -1),
+			BPF_ALU64_IMM(BPF_LSH, BPF_REG_2, 32),
+			BPF_ALU64_IMM(BPF_OR, BPF_REG_2, 0xffff),
+			BPF_ALU32_REG(BPF_XOR, BPF_REG_2, BPF_REG_2),
+			BPF_MOV32_IMM(BPF_REG_0, 2),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_2, 0, 1),
+			BPF_MOV32_IMM(BPF_REG_0, 1),
+			BPF_EXIT_INSN(),
+		},
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+		.result = ACCEPT,
+		.retval = 1,
+	},
 	{
 		"empty prog",
 		.insns = {