[PATCH bpf-next v2 8/8] bpf/tests: add tests for cpuv4 instructions

Puranjay Mohan
2023-09-06T18:35:04Z

The BPF JITs now support cpuv4 instructions. Add tests for these new
instructions to the test suite:

1. Sign extended Load
2. Sign extended Mov
3. Unconditional byte swap
4. Unconditional jump with 32-bit offset
5. Signed division and modulo

Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
---
include/linux/filter.h | 50 +++++-
lib/test_bpf.c | 371 +++++++++++++++++++++++++++++++++++++++++
2 files changed, 417 insertions(+), 4 deletions(-)

diff --git a/include/linux/filter.h b/include/linux/filter.h
index 761af6b3cf2b..0138832ad571 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -117,21 +117,25 @@ struct ctl_table_header;

/* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */

-#define BPF_ALU64_IMM(OP, DST, IMM) \
+#define BPF_ALU64_IMM_OFF(OP, DST, IMM, OFF) \
((struct bpf_insn) { \
.code = BPF_ALU64 | BPF_OP(OP) | BPF_K, \
.dst_reg = DST, \
.src_reg = 0, \
- .off = 0, \
+ .off = OFF, \
.imm = IMM })
+#define BPF_ALU64_IMM(OP, DST, IMM) \
+ BPF_ALU64_IMM_OFF(OP, DST, IMM, 0)

-#define BPF_ALU32_IMM(OP, DST, IMM) \
+#define BPF_ALU32_IMM_OFF(OP, DST, IMM, OFF) \
((struct bpf_insn) { \
.code = BPF_ALU | BPF_OP(OP) | BPF_K, \
.dst_reg = DST, \
.src_reg = 0, \
- .off = 0, \
+ .off = OFF, \
.imm = IMM })
+#define BPF_ALU32_IMM(OP, DST, IMM) \
+ BPF_ALU32_IMM_OFF(OP, DST, IMM, 0)

/* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */

@@ -143,6 +147,16 @@ struct ctl_table_header;
.off = 0, \
.imm = LEN })

+/* Byte Swap, bswap16/32/64 */
+
+#define BPF_BSWAP(DST, LEN) \
+ ((struct bpf_insn) { \
+ .code = BPF_ALU64 | BPF_END | BPF_SRC(BPF_TO_LE), \
+ .dst_reg = DST, \
+ .src_reg = 0, \
+ .off = 0, \
+ .imm = LEN })
+
/* Short form of mov, dst_reg = src_reg */

#define BPF_MOV64_REG(DST, SRC) \
@@ -179,6 +193,24 @@ struct ctl_table_header;
.off = 0, \
.imm = IMM })

+/* Short form of movsx, dst_reg = (s8,s16,s32)src_reg */
+
+#define BPF_MOVSX64_REG(DST, SRC, OFF) \
+ ((struct bpf_insn) { \
+ .code = BPF_ALU64 | BPF_MOV | BPF_X, \
+ .dst_reg = DST, \
+ .src_reg = SRC, \
+ .off = OFF, \
+ .imm = 0 })
+
+#define BPF_MOVSX32_REG(DST, SRC, OFF) \
+ ((struct bpf_insn) { \
+ .code = BPF_ALU | BPF_MOV | BPF_X, \
+ .dst_reg = DST, \
+ .src_reg = SRC, \
+ .off = OFF, \
+ .imm = 0 })
+
/* Special form of mov32, used for doing explicit zero extension on dst. */
#define BPF_ZEXT_REG(DST) \
((struct bpf_insn) { \
@@ -263,6 +295,16 @@ static inline bool insn_is_zext(const struct bpf_insn *insn)
.off = OFF, \
.imm = 0 })

+/* Memory load, dst_reg = *(signed size *) (src_reg + off16) */
+
+#define BPF_LDX_MEMSX(SIZE, DST, SRC, OFF) \
+ ((struct bpf_insn) { \
+ .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEMSX, \
+ .dst_reg = DST, \
+ .src_reg = SRC, \
+ .off = OFF, \
+ .imm = 0 })
+
/* Memory store, *(uint *) (dst_reg + off16) = src_reg */

#define BPF_STX_MEM(SIZE, DST, SRC, OFF) \
diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index ecde4216201e..7916503e6a6a 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -5111,6 +5111,104 @@ static struct bpf_test tests[] = {
{ },
{ { 0, 0xffffffff } }
},
+ /* MOVSX32 */
+ {
+ "ALU_MOVSX | BPF_B",
+ .u.insns_int = {
+ BPF_LD_IMM64(R2, 0x00000000ffffffefLL),
+ BPF_LD_IMM64(R3, 0xdeadbeefdeadbeefLL),
+ BPF_MOVSX32_REG(R1, R3, 8),
+ BPF_JMP_REG(BPF_JEQ, R2, R1, 2),
+ BPF_MOV32_IMM(R0, 2),
+ BPF_EXIT_INSN(),
+ BPF_MOV32_IMM(R0, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0x1 } },
+ },
+ {
+ "ALU_MOVSX | BPF_H",
+ .u.insns_int = {
+ BPF_LD_IMM64(R2, 0x00000000ffffbeefLL),
+ BPF_LD_IMM64(R3, 0xdeadbeefdeadbeefLL),
+ BPF_MOVSX32_REG(R1, R3, 16),
+ BPF_JMP_REG(BPF_JEQ, R2, R1, 2),
+ BPF_MOV32_IMM(R0, 2),
+ BPF_EXIT_INSN(),
+ BPF_MOV32_IMM(R0, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0x1 } },
+ },
+ {
+ "ALU_MOVSX | BPF_W",
+ .u.insns_int = {
+ BPF_LD_IMM64(R2, 0x00000000deadbeefLL),
+ BPF_LD_IMM64(R3, 0xdeadbeefdeadbeefLL),
+ BPF_MOVSX32_REG(R1, R3, 32),
+ BPF_JMP_REG(BPF_JEQ, R2, R1, 2),
+ BPF_MOV32_IMM(R0, 2),
+ BPF_EXIT_INSN(),
+ BPF_MOV32_IMM(R0, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0x1 } },
+ },
+ /* MOVSX64 REG */
+ {
+ "ALU64_MOVSX | BPF_B",
+ .u.insns_int = {
+ BPF_LD_IMM64(R2, 0xffffffffffffffefLL),
+ BPF_LD_IMM64(R3, 0xdeadbeefdeadbeefLL),
+ BPF_MOVSX64_REG(R1, R3, 8),
+ BPF_JMP_REG(BPF_JEQ, R2, R1, 2),
+ BPF_MOV32_IMM(R0, 2),
+ BPF_EXIT_INSN(),
+ BPF_MOV32_IMM(R0, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0x1 } },
+ },
+ {
+ "ALU64_MOVSX | BPF_H",
+ .u.insns_int = {
+ BPF_LD_IMM64(R2, 0xffffffffffffbeefLL),
+ BPF_LD_IMM64(R3, 0xdeadbeefdeadbeefLL),
+ BPF_MOVSX64_REG(R1, R3, 16),
+ BPF_JMP_REG(BPF_JEQ, R2, R1, 2),
+ BPF_MOV32_IMM(R0, 2),
+ BPF_EXIT_INSN(),
+ BPF_MOV32_IMM(R0, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0x1 } },
+ },
+ {
+ "ALU64_MOVSX | BPF_W",
+ .u.insns_int = {
+ BPF_LD_IMM64(R2, 0xffffffffdeadbeefLL),
+ BPF_LD_IMM64(R3, 0xdeadbeefdeadbeefLL),
+ BPF_MOVSX64_REG(R1, R3, 32),
+ BPF_JMP_REG(BPF_JEQ, R2, R1, 2),
+ BPF_MOV32_IMM(R0, 2),
+ BPF_EXIT_INSN(),
+ BPF_MOV32_IMM(R0, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0x1 } },
+ },
/* BPF_ALU | BPF_ADD | BPF_X */
{
"ALU_ADD_X: 1 + 2 = 3",
@@ -6105,6 +6203,106 @@ static struct bpf_test tests[] = {
{ },
{ { 0, 2 } },
},
+ /* BPF_ALU | BPF_DIV | BPF_X off=1 (SDIV) */
+ {
+ "ALU_SDIV_X: -6 / 2 = -3",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, -6),
+ BPF_ALU32_IMM(BPF_MOV, R1, 2),
+ BPF_ALU32_REG_OFF(BPF_DIV, R0, R1, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, -3 } },
+ },
+ /* BPF_ALU | BPF_DIV | BPF_K off=1 (SDIV) */
+ {
+ "ALU_SDIV_K: -6 / 2 = -3",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, -6),
+ BPF_ALU32_IMM_OFF(BPF_DIV, R0, 2, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, -3 } },
+ },
+ /* BPF_ALU64 | BPF_DIV | BPF_X off=1 (SDIV64) */
+ {
+ "ALU64_SDIV_X: -6 / 2 = -3",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, -6),
+ BPF_ALU32_IMM(BPF_MOV, R1, 2),
+ BPF_ALU64_REG_OFF(BPF_DIV, R0, R1, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, -3 } },
+ },
+ /* BPF_ALU64 | BPF_DIV | BPF_K off=1 (SDIV64) */
+ {
+ "ALU64_SDIV_K: -6 / 2 = -3",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, -6),
+ BPF_ALU64_IMM_OFF(BPF_DIV, R0, 2, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, -3 } },
+ },
+ /* BPF_ALU | BPF_MOD | BPF_X off=1 (SMOD) */
+ {
+ "ALU_SMOD_X: -7 % 2 = -1",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, -7),
+ BPF_ALU32_IMM(BPF_MOV, R1, 2),
+ BPF_ALU32_REG_OFF(BPF_MOD, R0, R1, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, -1 } },
+ },
+ /* BPF_ALU | BPF_MOD | BPF_K off=1 (SMOD) */
+ {
+ "ALU_SMOD_K: -7 % 2 = -1",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, -7),
+ BPF_ALU32_IMM_OFF(BPF_MOD, R0, 2, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, -1 } },
+ },
+ /* BPF_ALU64 | BPF_MOD | BPF_X off=1 (SMOD64) */
+ {
+ "ALU64_SMOD_X: -7 % 2 = -1",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, -7),
+ BPF_ALU32_IMM(BPF_MOV, R1, 2),
+ BPF_ALU64_REG_OFF(BPF_MOD, R0, R1, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, -1 } },
+ },
+ /* BPF_ALU64 | BPF_MOD | BPF_K off=1 (SMOD64) */
+ {
+ "ALU64_SMOD_X: -7 % 2 = -1",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, -7),
+ BPF_ALU64_IMM_OFF(BPF_MOD, R0, 2, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, -1 } },
+ },
/* BPF_ALU | BPF_AND | BPF_X */
{
"ALU_AND_X: 3 & 2 = 2",
@@ -7837,6 +8035,104 @@ static struct bpf_test tests[] = {
{ },
{ { 0, (u32) (cpu_to_le64(0xfedcba9876543210ULL) >> 32) } },
},
+ /* BSWAP */
+ {
+ "BSWAP 16: 0x0123456789abcdef -> 0xefcd",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, 0x0123456789abcdefLL),
+ BPF_BSWAP(R0, 16),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0xefcd } },
+ },
+ {
+ "BSWAP 32: 0x0123456789abcdef -> 0xefcdab89",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, 0x0123456789abcdefLL),
+ BPF_BSWAP(R0, 32),
+ BPF_ALU64_REG(BPF_MOV, R1, R0),
+ BPF_ALU64_IMM(BPF_RSH, R1, 32),
+ BPF_ALU32_REG(BPF_ADD, R0, R1), /* R1 = 0 */
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0xefcdab89 } },
+ },
+ {
+ "BSWAP 64: 0x0123456789abcdef -> 0x67452301",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, 0x0123456789abcdefLL),
+ BPF_BSWAP(R0, 64),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0x67452301 } },
+ },
+ {
+ "BSWAP 64: 0x0123456789abcdef >> 32 -> 0xefcdab89",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, 0x0123456789abcdefLL),
+ BPF_BSWAP(R0, 64),
+ BPF_ALU64_IMM(BPF_RSH, R0, 32),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0xefcdab89 } },
+ },
+ /* BSWAP, reversed */
+ {
+ "BSWAP 16: 0xfedcba9876543210 -> 0x1032",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, 0xfedcba9876543210ULL),
+ BPF_BSWAP(R0, 16),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0x1032 } },
+ },
+ {
+ "BSWAP 32: 0xfedcba9876543210 -> 0x10325476",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, 0xfedcba9876543210ULL),
+ BPF_BSWAP(R0, 32),
+ BPF_ALU64_REG(BPF_MOV, R1, R0),
+ BPF_ALU64_IMM(BPF_RSH, R1, 32),
+ BPF_ALU32_REG(BPF_ADD, R0, R1), /* R1 = 0 */
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0x10325476 } },
+ },
+ {
+ "BSWAP 64: 0xfedcba9876543210 -> 0x98badcfe",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, 0xfedcba9876543210ULL),
+ BPF_BSWAP(R0, 64),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0x98badcfe } },
+ },
+ {
+ "BSWAP 64: 0xfedcba9876543210 >> 32 -> 0x10325476",
+ .u.insns_int = {
+ BPF_LD_IMM64(R0, 0xfedcba9876543210ULL),
+ BPF_BSWAP(R0, 64),
+ BPF_ALU64_IMM(BPF_RSH, R0, 32),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0x10325476 } },
+ },
/* BPF_LDX_MEM B/H/W/DW */
{
"BPF_LDX_MEM | BPF_B, base",
@@ -8228,6 +8524,67 @@ static struct bpf_test tests[] = {
{ { 32, 0 } },
.stack_depth = 0,
},
+ /* BPF_LDX_MEMSX B/H/W */
+ {
+ "BPF_LDX_MEMSX | BPF_B",
+ .u.insns_int = {
+ BPF_LD_IMM64(R1, 0xdead0000000000f0ULL),
+ BPF_LD_IMM64(R2, 0xfffffffffffffff0ULL),
+ BPF_STX_MEM(BPF_DW, R10, R1, -8),
+#ifdef __BIG_ENDIAN
+ BPF_LDX_MEMSX(BPF_B, R0, R10, -1),
+#else
+ BPF_LDX_MEMSX(BPF_B, R0, R10, -8),
+#endif
+ BPF_JMP_REG(BPF_JNE, R0, R2, 1),
+ BPF_ALU64_IMM(BPF_MOV, R0, 0),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0 } },
+ .stack_depth = 8,
+ },
+ {
+ "BPF_LDX_MEMSX | BPF_H",
+ .u.insns_int = {
+ BPF_LD_IMM64(R1, 0xdead00000000f123ULL),
+ BPF_LD_IMM64(R2, 0xfffffffffffff123ULL),
+ BPF_STX_MEM(BPF_DW, R10, R1, -8),
+#ifdef __BIG_ENDIAN
+ BPF_LDX_MEMSX(BPF_H, R0, R10, -2),
+#else
+ BPF_LDX_MEMSX(BPF_H, R0, R10, -8),
+#endif
+ BPF_JMP_REG(BPF_JNE, R0, R2, 1),
+ BPF_ALU64_IMM(BPF_MOV, R0, 0),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0 } },
+ .stack_depth = 8,
+ },
+ {
+ "BPF_LDX_MEMSX | BPF_W",
+ .u.insns_int = {
+ BPF_LD_IMM64(R1, 0x00000000deadbeefULL),
+ BPF_LD_IMM64(R2, 0xffffffffdeadbeefULL),
+ BPF_STX_MEM(BPF_DW, R10, R1, -8),
+#ifdef __BIG_ENDIAN
+ BPF_LDX_MEMSX(BPF_W, R0, R10, -4),
+#else
+ BPF_LDX_MEMSX(BPF_W, R0, R10, -8),
+#endif
+ BPF_JMP_REG(BPF_JNE, R0, R2, 1),
+ BPF_ALU64_IMM(BPF_MOV, R0, 0),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 0 } },
+ .stack_depth = 8,
+ },
/* BPF_STX_MEM B/H/W/DW */
{
"BPF_STX_MEM | BPF_B",
@@ -9474,6 +9831,20 @@ static struct bpf_test tests[] = {
{ },
{ { 0, 1 } },
},
+ /* BPF_JMP32 | BPF_JA */
+ {
+ "JMP32_JA: Unconditional jump: if (true) return 1",
+ .u.insns_int = {
+ BPF_ALU32_IMM(BPF_MOV, R0, 0),
+ BPF_JMP32_IMM(BPF_JA, 0, 1, 0),
+ BPF_EXIT_INSN(),
+ BPF_ALU32_IMM(BPF_MOV, R0, 1),
+ BPF_EXIT_INSN(),
+ },
+ INTERNAL,
+ { },
+ { { 0, 1 } },
+ },
/* BPF_JMP | BPF_JSLT | BPF_K */
{
"JMP_JSLT_K: Signed jump: if (-2 < -1) return 1",
--
2.39.2