selftests/bpf: Add tests for reference tracking (b584ab88) · Commits · 戴 / test

tools/testing/selftests/bpf/test_verifier.c

+759 −0

Original line number	Diff line number	Diff line
		@@ -3,6 +3,7 @@
		*
		* Copyright (c) 2014 PLUMgrid, http://plumgrid.com
		* Copyright (c) 2017 Facebook
		* Copyright (c) 2018 Covalent IO, Inc. http://covalent.io
		*
		* This program is free software; you can redistribute it and/or
		* modify it under the terms of version 2 of the GNU General Public
		@@ -178,6 +179,24 @@ static void bpf_fill_rand_ld_dw(struct bpf_test *self)
		self->retval = (uint32_t)res;
		}

		/* BPF_SK_LOOKUP contains 13 instructions, if you need to fix up maps */
		#define BPF_SK_LOOKUP \
		/* struct bpf_sock_tuple tuple = {} */ \
		BPF_MOV64_IMM(BPF_REG_2, 0), \
		BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_2, -8), \
		BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -16), \
		BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -24), \
		BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -32), \
		BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -40), \
		BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -48), \
		/* sk = sk_lookup_tcp(ctx, &tuple, sizeof tuple, 0, 0) */ \
		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), \
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -48), \
		BPF_MOV64_IMM(BPF_REG_3, sizeof(struct bpf_sock_tuple)), \
		BPF_MOV64_IMM(BPF_REG_4, 0), \
		BPF_MOV64_IMM(BPF_REG_5, 0), \
		BPF_EMIT_CALL(BPF_FUNC_sk_lookup_tcp)

		static struct bpf_test tests[] = {
		{
		"add+sub+mul",
		@@ -2707,6 +2726,137 @@ static struct bpf_test tests[] = {
		.errstr = "same insn cannot be used with different pointers",
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		},
		{
		"unpriv: spill/fill of different pointers stx - ctx and sock",
		.insns = {
		BPF_MOV64_REG(BPF_REG_8, BPF_REG_1),
		/* struct bpf_sock sock = bpf_sock_lookup(...); /
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
		/* u64 foo; */
		/* void target = &foo; /
		BPF_ALU64_REG(BPF_MOV, BPF_REG_6, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, -8),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_8),
		/* if (skb == NULL) target = sock; /
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
		BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_2, 0),
		/* else target = skb; /
		BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 1),
		BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 0),
		/* struct __sk_buff skb = target; */
		BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_6, 0),
		/* skb->mark = 42; */
		BPF_MOV64_IMM(BPF_REG_3, 42),
		BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_3,
		offsetof(struct __sk_buff, mark)),
		/* if (sk) bpf_sk_release(sk) */
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_EXIT_INSN(),
		},
		.result = REJECT,
		.errstr = "type=ctx expected=sock",
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		},
		{
		"unpriv: spill/fill of different pointers stx - leak sock",
		.insns = {
		BPF_MOV64_REG(BPF_REG_8, BPF_REG_1),
		/* struct bpf_sock sock = bpf_sock_lookup(...); /
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
		/* u64 foo; */
		/* void target = &foo; /
		BPF_ALU64_REG(BPF_MOV, BPF_REG_6, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, -8),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_8),
		/* if (skb == NULL) target = sock; /
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
		BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_2, 0),
		/* else target = skb; /
		BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 1),
		BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 0),
		/* struct __sk_buff skb = target; */
		BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_6, 0),
		/* skb->mark = 42; */
		BPF_MOV64_IMM(BPF_REG_3, 42),
		BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_3,
		offsetof(struct __sk_buff, mark)),
		BPF_EXIT_INSN(),
		},
		.result = REJECT,
		//.errstr = "same insn cannot be used with different pointers",
		.errstr = "Unreleased reference",
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		},
		{
		"unpriv: spill/fill of different pointers stx - sock and ctx (read)",
		.insns = {
		BPF_MOV64_REG(BPF_REG_8, BPF_REG_1),
		/* struct bpf_sock sock = bpf_sock_lookup(...); /
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
		/* u64 foo; */
		/* void target = &foo; /
		BPF_ALU64_REG(BPF_MOV, BPF_REG_6, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, -8),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_8),
		/* if (skb) target = skb /
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
		BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 0),
		/* else target = sock /
		BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 1),
		BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_2, 0),
		/* struct bpf_sock sk = target; */
		BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_6, 0),
		/* if (sk) u32 foo = sk->mark; bpf_sk_release(sk); */
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 2),
		BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
		offsetof(struct bpf_sock, mark)),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_EXIT_INSN(),
		},
		.result = REJECT,
		.errstr = "same insn cannot be used with different pointers",
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		},
		{
		"unpriv: spill/fill of different pointers stx - sock and ctx (write)",
		.insns = {
		BPF_MOV64_REG(BPF_REG_8, BPF_REG_1),
		/* struct bpf_sock sock = bpf_sock_lookup(...); /
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
		/* u64 foo; */
		/* void target = &foo; /
		BPF_ALU64_REG(BPF_MOV, BPF_REG_6, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, -8),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_8),
		/* if (skb) target = skb /
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
		BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 0),
		/* else target = sock /
		BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 1),
		BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_2, 0),
		/* struct bpf_sock sk = target; */
		BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_6, 0),
		/* if (sk) sk->mark = 42; bpf_sk_release(sk); */
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 3),
		BPF_MOV64_IMM(BPF_REG_3, 42),
		BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_3,
		offsetof(struct bpf_sock, mark)),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_EXIT_INSN(),
		},
		.result = REJECT,
		//.errstr = "same insn cannot be used with different pointers",
		.errstr = "cannot write into socket",
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		},
		{
		"unpriv: spill/fill of different pointers ldx",
		.insns = {
		@@ -12557,6 +12707,214 @@ static struct bpf_test tests[] = {
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		},
		{
		"reference tracking: leak potential reference",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_0), /* leak reference */
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "Unreleased reference",
		.result = REJECT,
		},
		{
		"reference tracking: leak potential reference on stack",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8),
		BPF_STX_MEM(BPF_DW, BPF_REG_4, BPF_REG_0, 0),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "Unreleased reference",
		.result = REJECT,
		},
		{
		"reference tracking: leak potential reference on stack 2",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8),
		BPF_STX_MEM(BPF_DW, BPF_REG_4, BPF_REG_0, 0),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_ST_MEM(BPF_DW, BPF_REG_4, 0, 0),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "Unreleased reference",
		.result = REJECT,
		},
		{
		"reference tracking: zero potential reference",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_IMM(BPF_REG_0, 0), /* leak reference */
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "Unreleased reference",
		.result = REJECT,
		},
		{
		"reference tracking: copy and zero potential references",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_7, BPF_REG_0),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_MOV64_IMM(BPF_REG_7, 0), /* leak reference */
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "Unreleased reference",
		.result = REJECT,
		},
		{
		"reference tracking: release reference without check",
		.insns = {
		BPF_SK_LOOKUP,
		/* reference in r0 may be NULL */
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_MOV64_IMM(BPF_REG_2, 0),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "type=sock_or_null expected=sock",
		.result = REJECT,
		},
		{
		"reference tracking: release reference",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		},
		{
		"reference tracking: release reference 2",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
		BPF_EXIT_INSN(),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		},
		{
		"reference tracking: release reference twice",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "type=inv expected=sock",
		.result = REJECT,
		},
		{
		"reference tracking: release reference twice inside branch",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3), /* goto end */
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "type=inv expected=sock",
		.result = REJECT,
		},
		{
		"reference tracking: alloc, check, free in one subbranch",
		.insns = {
		BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
		offsetof(struct __sk_buff, data)),
		BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
		offsetof(struct __sk_buff, data_end)),
		BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 16),
		/* if (offsetof(skb, mark) > data_len) exit; */
		BPF_JMP_REG(BPF_JLE, BPF_REG_0, BPF_REG_3, 1),
		BPF_EXIT_INSN(),
		BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_2,
		offsetof(struct __sk_buff, mark)),
		BPF_SK_LOOKUP,
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 1), /* mark == 0? */
		/* Leak reference in R0 */
		BPF_EXIT_INSN(),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2), /* sk NULL? */
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "Unreleased reference",
		.result = REJECT,
		},
		{
		"reference tracking: alloc, check, free in both subbranches",
		.insns = {
		BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
		offsetof(struct __sk_buff, data)),
		BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
		offsetof(struct __sk_buff, data_end)),
		BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 16),
		/* if (offsetof(skb, mark) > data_len) exit; */
		BPF_JMP_REG(BPF_JLE, BPF_REG_0, BPF_REG_3, 1),
		BPF_EXIT_INSN(),
		BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_2,
		offsetof(struct __sk_buff, mark)),
		BPF_SK_LOOKUP,
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 4), /* mark == 0? */
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2), /* sk NULL? */
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2), /* sk NULL? */
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		},
		{
		"reference tracking in call: free reference in subprog",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), /* unchecked reference */
		BPF_RAW_INSN(BPF_JMP \| BPF_CALL, 0, 1, 0, 2),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_EXIT_INSN(),

		/* subprog 1 */
		BPF_MOV64_REG(BPF_REG_2, BPF_REG_1),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_2, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		},
		{
		"pass modified ctx pointer to helper, 1",
		.insns = {
		@@ -12627,6 +12985,407 @@ static struct bpf_test tests[] = {
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		},
		{
		"reference tracking in call: free reference in subprog and outside",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), /* unchecked reference */
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
		BPF_RAW_INSN(BPF_JMP \| BPF_CALL, 0, 1, 0, 3),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),

		/* subprog 1 */
		BPF_MOV64_REG(BPF_REG_2, BPF_REG_1),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_2, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "type=inv expected=sock",
		.result = REJECT,
		},
		{
		"reference tracking in call: alloc & leak reference in subprog",
		.insns = {
		BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8),
		BPF_RAW_INSN(BPF_JMP \| BPF_CALL, 0, 1, 0, 3),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_EXIT_INSN(),

		/* subprog 1 */
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_4),
		BPF_SK_LOOKUP,
		/* spill unchecked sk_ptr into stack of caller */
		BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_0, 0),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "Unreleased reference",
		.result = REJECT,
		},
		{
		"reference tracking in call: alloc in subprog, release outside",
		.insns = {
		BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
		BPF_RAW_INSN(BPF_JMP \| BPF_CALL, 0, 1, 0, 4),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),

		/* subprog 1 */
		BPF_SK_LOOKUP,
		BPF_EXIT_INSN(), /* return sk */
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.retval = POINTER_VALUE,
		.result = ACCEPT,
		},
		{
		"reference tracking in call: sk_ptr leak into caller stack",
		.insns = {
		BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8),
		BPF_RAW_INSN(BPF_JMP \| BPF_CALL, 0, 1, 0, 2),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_EXIT_INSN(),

		/* subprog 1 */
		BPF_MOV64_REG(BPF_REG_5, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, -8),
		BPF_STX_MEM(BPF_DW, BPF_REG_5, BPF_REG_4, 0),
		BPF_RAW_INSN(BPF_JMP \| BPF_CALL, 0, 1, 0, 5),
		/* spill unchecked sk_ptr into stack of caller */
		BPF_MOV64_REG(BPF_REG_5, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, -8),
		BPF_LDX_MEM(BPF_DW, BPF_REG_4, BPF_REG_5, 0),
		BPF_STX_MEM(BPF_DW, BPF_REG_4, BPF_REG_0, 0),
		BPF_EXIT_INSN(),

		/* subprog 2 */
		BPF_SK_LOOKUP,
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "Unreleased reference",
		.result = REJECT,
		},
		{
		"reference tracking in call: sk_ptr spill into caller stack",
		.insns = {
		BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8),
		BPF_RAW_INSN(BPF_JMP \| BPF_CALL, 0, 1, 0, 2),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_EXIT_INSN(),

		/* subprog 1 */
		BPF_MOV64_REG(BPF_REG_5, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, -8),
		BPF_STX_MEM(BPF_DW, BPF_REG_5, BPF_REG_4, 0),
		BPF_RAW_INSN(BPF_JMP \| BPF_CALL, 0, 1, 0, 8),
		/* spill unchecked sk_ptr into stack of caller */
		BPF_MOV64_REG(BPF_REG_5, BPF_REG_10),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, -8),
		BPF_LDX_MEM(BPF_DW, BPF_REG_4, BPF_REG_5, 0),
		BPF_STX_MEM(BPF_DW, BPF_REG_4, BPF_REG_0, 0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
		/* now the sk_ptr is verified, free the reference */
		BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_4, 0),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),

		/* subprog 2 */
		BPF_SK_LOOKUP,
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		},
		{
		"reference tracking: allow LD_ABS",
		.insns = {
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_LD_ABS(BPF_B, 0),
		BPF_LD_ABS(BPF_H, 0),
		BPF_LD_ABS(BPF_W, 0),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		},
		{
		"reference tracking: forbid LD_ABS while holding reference",
		.insns = {
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
		BPF_SK_LOOKUP,
		BPF_LD_ABS(BPF_B, 0),
		BPF_LD_ABS(BPF_H, 0),
		BPF_LD_ABS(BPF_W, 0),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "BPF_LD_[ABS\|IND] cannot be mixed with socket references",
		.result = REJECT,
		},
		{
		"reference tracking: allow LD_IND",
		.insns = {
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_MOV64_IMM(BPF_REG_7, 1),
		BPF_LD_IND(BPF_W, BPF_REG_7, -0x200000),
		BPF_MOV64_REG(BPF_REG_0, BPF_REG_7),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		.retval = 1,
		},
		{
		"reference tracking: forbid LD_IND while holding reference",
		.insns = {
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_4, BPF_REG_0),
		BPF_MOV64_IMM(BPF_REG_7, 1),
		BPF_LD_IND(BPF_W, BPF_REG_7, -0x200000),
		BPF_MOV64_REG(BPF_REG_0, BPF_REG_7),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_4),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "BPF_LD_[ABS\|IND] cannot be mixed with socket references",
		.result = REJECT,
		},
		{
		"reference tracking: check reference or tail call",
		.insns = {
		BPF_MOV64_REG(BPF_REG_7, BPF_REG_1),
		BPF_SK_LOOKUP,
		/* if (sk) bpf_sk_release() */
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 7),
		/* bpf_tail_call() */
		BPF_MOV64_IMM(BPF_REG_3, 2),
		BPF_LD_MAP_FD(BPF_REG_2, 0),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
		BPF_RAW_INSN(BPF_JMP \| BPF_CALL, 0, 0, 0,
		BPF_FUNC_tail_call),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_EXIT_INSN(),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.fixup_prog1 = { 17 },
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		},
		{
		"reference tracking: release reference then tail call",
		.insns = {
		BPF_MOV64_REG(BPF_REG_7, BPF_REG_1),
		BPF_SK_LOOKUP,
		/* if (sk) bpf_sk_release() */
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		/* bpf_tail_call() */
		BPF_MOV64_IMM(BPF_REG_3, 2),
		BPF_LD_MAP_FD(BPF_REG_2, 0),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
		BPF_RAW_INSN(BPF_JMP \| BPF_CALL, 0, 0, 0,
		BPF_FUNC_tail_call),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_EXIT_INSN(),
		},
		.fixup_prog1 = { 18 },
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		},
		{
		"reference tracking: leak possible reference over tail call",
		.insns = {
		BPF_MOV64_REG(BPF_REG_7, BPF_REG_1),
		/* Look up socket and store in REG_6 */
		BPF_SK_LOOKUP,
		/* bpf_tail_call() */
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
		BPF_MOV64_IMM(BPF_REG_3, 2),
		BPF_LD_MAP_FD(BPF_REG_2, 0),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
		BPF_RAW_INSN(BPF_JMP \| BPF_CALL, 0, 0, 0,
		BPF_FUNC_tail_call),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		/* if (sk) bpf_sk_release() */
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.fixup_prog1 = { 16 },
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "tail_call would lead to reference leak",
		.result = REJECT,
		},
		{
		"reference tracking: leak checked reference over tail call",
		.insns = {
		BPF_MOV64_REG(BPF_REG_7, BPF_REG_1),
		/* Look up socket and store in REG_6 */
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
		/* if (!sk) goto end */
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7),
		/* bpf_tail_call() */
		BPF_MOV64_IMM(BPF_REG_3, 0),
		BPF_LD_MAP_FD(BPF_REG_2, 0),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
		BPF_RAW_INSN(BPF_JMP \| BPF_CALL, 0, 0, 0,
		BPF_FUNC_tail_call),
		BPF_MOV64_IMM(BPF_REG_0, 0),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.fixup_prog1 = { 17 },
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "tail_call would lead to reference leak",
		.result = REJECT,
		},
		{
		"reference tracking: mangle and release sock_or_null",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 5),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "R1 pointer arithmetic on sock_or_null prohibited",
		.result = REJECT,
		},
		{
		"reference tracking: mangle and release sock",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 5),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "R1 pointer arithmetic on sock prohibited",
		.result = REJECT,
		},
		{
		"reference tracking: access member",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3),
		BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_0, 4),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		},
		{
		"reference tracking: write to member",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 5),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
		BPF_LD_IMM64(BPF_REG_2, 42),
		BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_2,
		offsetof(struct bpf_sock, mark)),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_LD_IMM64(BPF_REG_0, 0),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "cannot write into socket",
		.result = REJECT,
		},
		{
		"reference tracking: invalid 64-bit access of member",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3),
		BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_0, 0),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "invalid bpf_sock access off=0 size=8",
		.result = REJECT,
		},
		{
		"reference tracking: access after release",
		.insns = {
		BPF_SK_LOOKUP,
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 0),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.errstr = "!read_ok",
		.result = REJECT,
		},
		{
		"reference tracking: direct access for lookup",
		.insns = {
		/* Check that the packet is at least 64B long */
		BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
		offsetof(struct __sk_buff, data)),
		BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
		offsetof(struct __sk_buff, data_end)),
		BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 64),
		BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_3, 9),
		/* sk = sk_lookup_tcp(ctx, skb->data, ...) */
		BPF_MOV64_IMM(BPF_REG_3, sizeof(struct bpf_sock_tuple)),
		BPF_MOV64_IMM(BPF_REG_4, 0),
		BPF_MOV64_IMM(BPF_REG_5, 0),
		BPF_EMIT_CALL(BPF_FUNC_sk_lookup_tcp),
		BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
		BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3),
		BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_0, 4),
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
		BPF_EMIT_CALL(BPF_FUNC_sk_release),
		BPF_EXIT_INSN(),
		},
		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
		.result = ACCEPT,
		},
		};

		static int probe_filter_length(const struct bpf_insn *fp)

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