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[176.36.0.241]) by smtp.gmail.com with ESMTPSA id hg6-20020a05600c538600b003b47b80cec3sm168515wmb.42.2023.02.14.15.20.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Feb 2023 15:20:56 -0800 (PST) From: Eduard Zingerman To: bpf@vger.kernel.org, ast@kernel.org Cc: andrii@kernel.org, daniel@iogearbox.net, martin.lau@linux.dev, kernel-team@fb.com, yhs@fb.com, jose.marchesi@oracle.com, Eduard Zingerman Subject: [PATCH bpf-next v2 1/4] bpf: track immediate values written to stack by BPF_ST instruction Date: Wed, 15 Feb 2023 01:20:27 +0200 Message-Id: <20230214232030.1502829-2-eddyz87@gmail.com> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230214232030.1502829-1-eddyz87@gmail.com> References: <20230214232030.1502829-1-eddyz87@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net For aligned stack writes using BPF_ST instruction track stored values in a same way BPF_STX is handled, e.g. make sure that the following commands produce similar verifier knowledge: fp[-8] = 42; r1 = 42; fp[-8] = r1; This covers two cases: - non-null values written to stack are stored as spill of fake registers; - null values written to stack are stored as STACK_ZERO marks. Previously both cases above used STACK_MISC marks instead. Some verifier test cases relied on the old logic to obtain STACK_MISC marks for some stack values. These test cases are updated in the same commit to avoid failures during bisect. Signed-off-by: Eduard Zingerman --- kernel/bpf/verifier.c | 18 ++- .../bpf/verifier/bounds_mix_sign_unsign.c | 110 ++++++++++-------- 2 files changed, 80 insertions(+), 48 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 21e08c111702..c28afae60874 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3473,6 +3473,11 @@ static void save_register_state(struct bpf_func_state *state, scrub_spilled_slot(&state->stack[spi].slot_type[i - 1]); } +static bool is_bpf_st_mem(struct bpf_insn *insn) +{ + return BPF_CLASS(insn->code) == BPF_ST && BPF_MODE(insn->code) == BPF_MEM; +} + /* check_stack_{read,write}_fixed_off functions track spill/fill of registers, * stack boundary and alignment are checked in check_mem_access() */ @@ -3484,8 +3489,9 @@ static int check_stack_write_fixed_off(struct bpf_verifier_env *env, { struct bpf_func_state *cur; /* state of the current function */ int i, slot = -off - 1, spi = slot / BPF_REG_SIZE, err; - u32 dst_reg = env->prog->insnsi[insn_idx].dst_reg; + struct bpf_insn *insn = &env->prog->insnsi[insn_idx]; struct bpf_reg_state *reg = NULL; + u32 dst_reg = insn->dst_reg; err = grow_stack_state(state, round_up(slot + 1, BPF_REG_SIZE)); if (err) @@ -3538,6 +3544,13 @@ static int check_stack_write_fixed_off(struct bpf_verifier_env *env, return err; } save_register_state(state, spi, reg, size); + } else if (!reg && !(off % BPF_REG_SIZE) && is_bpf_st_mem(insn) && + insn->imm != 0 && env->bpf_capable) { + struct bpf_reg_state fake_reg = {}; + + __mark_reg_known(&fake_reg, (u32)insn->imm); + fake_reg.type = SCALAR_VALUE; + save_register_state(state, spi, &fake_reg, size); } else if (reg && is_spillable_regtype(reg->type)) { /* register containing pointer is being spilled into stack */ if (size != BPF_REG_SIZE) { @@ -3572,7 +3585,8 @@ static int check_stack_write_fixed_off(struct bpf_verifier_env *env, state->stack[spi].spilled_ptr.live |= REG_LIVE_WRITTEN; /* when we zero initialize stack slots mark them as such */ - if (reg && register_is_null(reg)) { + if ((reg && register_is_null(reg)) || + (!reg && is_bpf_st_mem(insn) && insn->imm == 0)) { /* backtracking doesn't work for STACK_ZERO yet. */ err = mark_chain_precision(env, value_regno); if (err) diff --git a/tools/testing/selftests/bpf/verifier/bounds_mix_sign_unsign.c b/tools/testing/selftests/bpf/verifier/bounds_mix_sign_unsign.c index c2aa6f26738b..bf82b923c5fe 100644 --- a/tools/testing/selftests/bpf/verifier/bounds_mix_sign_unsign.c +++ b/tools/testing/selftests/bpf/verifier/bounds_mix_sign_unsign.c @@ -1,13 +1,14 @@ { "bounds checks mixing signed and unsigned, positive bounds", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, 2), BPF_JMP_REG(BPF_JGE, BPF_REG_2, BPF_REG_1, 3), @@ -17,20 +18,21 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .errstr = "unbounded min value", .result = REJECT, }, { "bounds checks mixing signed and unsigned", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, -1), BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 3), @@ -40,20 +42,21 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .errstr = "unbounded min value", .result = REJECT, }, { "bounds checks mixing signed and unsigned, variant 2", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 9), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, -1), BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 5), @@ -65,20 +68,21 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .errstr = "unbounded min value", .result = REJECT, }, { "bounds checks mixing signed and unsigned, variant 3", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, -1), BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 4), @@ -89,20 +93,21 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .errstr = "unbounded min value", .result = REJECT, }, { "bounds checks mixing signed and unsigned, variant 4", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, 1), BPF_ALU64_REG(BPF_AND, BPF_REG_1, BPF_REG_2), @@ -112,19 +117,20 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .result = ACCEPT, }, { "bounds checks mixing signed and unsigned, variant 5", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 9), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, -1), BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 5), @@ -135,17 +141,20 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .errstr = "unbounded min value", .result = REJECT, }, { "bounds checks mixing signed and unsigned, variant 6", .insns = { + BPF_MOV64_REG(BPF_REG_9, BPF_REG_1), + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), + BPF_MOV64_REG(BPF_REG_1, BPF_REG_9), BPF_MOV64_IMM(BPF_REG_2, 0), BPF_MOV64_REG(BPF_REG_3, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, -512), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), BPF_LDX_MEM(BPF_DW, BPF_REG_4, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_6, -1), BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_6, 5), @@ -163,13 +172,14 @@ { "bounds checks mixing signed and unsigned, variant 7", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, 1024 * 1024 * 1024), BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 3), @@ -179,19 +189,20 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .result = ACCEPT, }, { "bounds checks mixing signed and unsigned, variant 8", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 9), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, -1), BPF_JMP_REG(BPF_JGT, BPF_REG_2, BPF_REG_1, 2), @@ -203,20 +214,21 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .errstr = "unbounded min value", .result = REJECT, }, { "bounds checks mixing signed and unsigned, variant 9", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 10), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 9), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_LD_IMM64(BPF_REG_2, -9223372036854775808ULL), BPF_JMP_REG(BPF_JGT, BPF_REG_2, BPF_REG_1, 2), @@ -228,19 +240,20 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .result = ACCEPT, }, { "bounds checks mixing signed and unsigned, variant 10", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 9), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, 0), BPF_JMP_REG(BPF_JGT, BPF_REG_2, BPF_REG_1, 2), @@ -252,20 +265,21 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .errstr = "unbounded min value", .result = REJECT, }, { "bounds checks mixing signed and unsigned, variant 11", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 9), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, -1), BPF_JMP_REG(BPF_JGE, BPF_REG_2, BPF_REG_1, 2), @@ -278,20 +292,21 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .errstr = "unbounded min value", .result = REJECT, }, { "bounds checks mixing signed and unsigned, variant 12", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 9), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, -6), BPF_JMP_REG(BPF_JGE, BPF_REG_2, BPF_REG_1, 2), @@ -303,20 +318,21 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .errstr = "unbounded min value", .result = REJECT, }, { "bounds checks mixing signed and unsigned, variant 13", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 5), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, 2), BPF_JMP_REG(BPF_JGE, BPF_REG_2, BPF_REG_1, 2), @@ -331,7 +347,7 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .errstr = "unbounded min value", .result = REJECT, }, @@ -340,13 +356,14 @@ .insns = { BPF_LDX_MEM(BPF_W, BPF_REG_9, BPF_REG_1, offsetof(struct __sk_buff, mark)), + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, -1), BPF_MOV64_IMM(BPF_REG_8, 2), @@ -360,20 +377,21 @@ BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, -3), BPF_JMP_IMM(BPF_JA, 0, 0, -7), }, - .fixup_map_hash_8b = { 4 }, + .fixup_map_hash_8b = { 6 }, .errstr = "unbounded min value", .result = REJECT, }, { "bounds checks mixing signed and unsigned, variant 15", .insns = { + BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns), + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -16), BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4), - BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3), BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16), BPF_MOV64_IMM(BPF_REG_2, -6), BPF_JMP_REG(BPF_JGE, BPF_REG_2, BPF_REG_1, 2), @@ -387,7 +405,7 @@ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .fixup_map_hash_8b = { 3 }, + .fixup_map_hash_8b = { 5 }, .errstr = "unbounded min value", .result = REJECT, }, From patchwork Tue Feb 14 23:20:28 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eduard Zingerman X-Patchwork-Id: 13141005 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 47FC9C05027 for ; Tue, 14 Feb 2023 23:21:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229650AbjBNXVD (ORCPT ); Tue, 14 Feb 2023 18:21:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230263AbjBNXVB (ORCPT ); Tue, 14 Feb 2023 18:21:01 -0500 Received: from mail-wm1-x32f.google.com (mail-wm1-x32f.google.com [IPv6:2a00:1450:4864:20::32f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5F8F828870 for ; Tue, 14 Feb 2023 15:20:59 -0800 (PST) Received: by mail-wm1-x32f.google.com with SMTP id az4-20020a05600c600400b003dff767a1f1so260934wmb.2 for ; Tue, 14 Feb 2023 15:20:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=0MZXg4FU2MR+bjabTpSovsdR/BPwkkH0jRfiKm/AsWg=; b=FP554M6W5hRpECFoYzT4VwXGKWFYK63lddG08pwGOuOJR8XINTbo8hFs0roAWtx4RV aBSoIQJI/kNDPSmiid/d+ZV9RYcc4Pjak+TlUYvj599JjUda6LV1XoMZVjxDEd3SCn68 630hCtdGc0NshyiBarg8NkHhBiGzbr91av6gsU2yty6QeN5WQMMTLcgnhjYq91yW5U1W EDAQewcRgDNlkyLRUMwpL7l7rc9ZhVxJMz/PwxfC84hpTyYD2tmWr2s+JNw+8MDgVsrv D2ih+wZjE6Hk2wB+cNcsxr0LTJIoPSAg5mbX315+XlFDBq74LTY5xoh3QavyG57w2ydE IuiQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=0MZXg4FU2MR+bjabTpSovsdR/BPwkkH0jRfiKm/AsWg=; b=KTb+OcCXWUb9x9XH90jKAdOWke2YbujSS5gtgCeeXe9JgbmB8mwtqBd6cIaObVveA/ ZIaFUe0NETa89dI0dD7k8LUi3DD7suSroKtMQ2q3BKz8LKKJSlfCuzI1YCarn/iAkQe+ eOvAf8fWq36khH4CeXQwJmxeMGMZldh0wFibhdFFxa6BnIXHJdQSUDbGrba/HRQKz/e8 OpXOZ+3fXYjKuH3iPqKIS+g4UbWSh7phLuqlbMujxKbF3sMP920e21bAiyuhoVdeosaX JyGHW3XoP16ekjxIg3p8xL/nlzTsIYhovIVFXK/R6GsWY9jE3c3y2nrF5w/PmUJakdfe VP2A== X-Gm-Message-State: AO0yUKXS6LcHhm7S0Nwf0NxnDvEc0DeTL+Ecnszu0OhUfViT3Zn80cPq +0cQNLZUwkGy8EoGn5TWfvbDMlbFa6GnMg== X-Google-Smtp-Source: AK7set8JcWyQWcl3fRvrXAVGlBU09SwyqJCYEE73ZGjeWnMrL5y5rFLVYYkHL5RvCLxWOn2UO8ZJNw== X-Received: by 2002:a05:600c:2b0f:b0:3da:22a6:7b6b with SMTP id y15-20020a05600c2b0f00b003da22a67b6bmr422382wme.13.1676416857566; Tue, 14 Feb 2023 15:20:57 -0800 (PST) Received: from bigfoot.. 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[176.36.0.241]) by smtp.gmail.com with ESMTPSA id hg6-20020a05600c538600b003b47b80cec3sm168515wmb.42.2023.02.14.15.20.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Feb 2023 15:20:57 -0800 (PST) From: Eduard Zingerman To: bpf@vger.kernel.org, ast@kernel.org Cc: andrii@kernel.org, daniel@iogearbox.net, martin.lau@linux.dev, kernel-team@fb.com, yhs@fb.com, jose.marchesi@oracle.com, Eduard Zingerman Subject: [PATCH bpf-next v2 2/4] selftests/bpf: check if verifier tracks constants spilled by BPF_ST_MEM Date: Wed, 15 Feb 2023 01:20:28 +0200 Message-Id: <20230214232030.1502829-3-eddyz87@gmail.com> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230214232030.1502829-1-eddyz87@gmail.com> References: <20230214232030.1502829-1-eddyz87@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Check that verifier tracks the value of 'imm' spilled to stack by BPF_ST_MEM instruction. Cover the following cases: - write of non-zero constant to stack; - write of a zero constant to stack. Signed-off-by: Eduard Zingerman --- .../selftests/bpf/verifier/bpf_st_mem.c | 37 +++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 tools/testing/selftests/bpf/verifier/bpf_st_mem.c diff --git a/tools/testing/selftests/bpf/verifier/bpf_st_mem.c b/tools/testing/selftests/bpf/verifier/bpf_st_mem.c new file mode 100644 index 000000000000..932903f9e585 --- /dev/null +++ b/tools/testing/selftests/bpf/verifier/bpf_st_mem.c @@ -0,0 +1,37 @@ +{ + "BPF_ST_MEM stack imm non-zero", + .insns = { + BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 42), + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, -42), + /* if value is tracked correctly R0 is zero */ + BPF_EXIT_INSN(), + }, + .result = ACCEPT, + /* Use prog type that requires return value in range [0, 1] */ + .prog_type = BPF_PROG_TYPE_SK_LOOKUP, + .expected_attach_type = BPF_SK_LOOKUP, + .runs = -1, +}, +{ + "BPF_ST_MEM stack imm zero", + .insns = { + /* mark stack 0000 0000 */ + BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), + /* read and sum a few bytes */ + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_10, -8), + BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1), + BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_10, -4), + BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1), + BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_10, -1), + BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1), + /* if value is tracked correctly R0 is zero */ + BPF_EXIT_INSN(), + }, + .result = ACCEPT, + /* Use prog type that requires return value in range [0, 1] */ + .prog_type = BPF_PROG_TYPE_SK_LOOKUP, + .expected_attach_type = BPF_SK_LOOKUP, + .runs = -1, +}, From patchwork Tue Feb 14 23:20:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eduard Zingerman X-Patchwork-Id: 13141008 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC64DC64EC7 for ; Tue, 14 Feb 2023 23:21:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230212AbjBNXVE (ORCPT ); Tue, 14 Feb 2023 18:21:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49254 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232056AbjBNXVB (ORCPT ); Tue, 14 Feb 2023 18:21:01 -0500 Received: from mail-wm1-x330.google.com (mail-wm1-x330.google.com [IPv6:2a00:1450:4864:20::330]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7B5BD30E95 for ; Tue, 14 Feb 2023 15:21:00 -0800 (PST) Received: by mail-wm1-x330.google.com with SMTP id l37-20020a05600c1d2500b003dfe46a9801so294257wms.0 for ; Tue, 14 Feb 2023 15:21:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=LuAKa6tuXX+2xublR81dUwnlNZg1dDcmp7dUGtQdU6o=; b=Ih4Qc31KYK8uH2IsTNdYNG55jcUepyBcBOA0DEzkrbs7iEwMdGdZiJtwv5qwoPtE5o 9izt/6PXwo/uxhxZz5hJyeKaPdarwN2Pn0i0r7b9tiLXz8mspQWbT/HCkLFXn0nEGTfu nWIgY6UBEbhTgt4WjKbPMIwTSjRy5u0eRVq+pqA8p3nDmCH7hF+WGAw75SaAPX4t9XH3 gjc+fCxGTVyAyAZJhhK7gjfEjD9StnPSQUBe35tltVdtnyc2L7+kpO1Jag1d7s87JUI1 VkNFupoCO3AYFSjndTJ2c/62PnSjHsSh8oG1rPpC/zaMQsItAqIF5rjvfRB2UuwYRkTy RKGA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=LuAKa6tuXX+2xublR81dUwnlNZg1dDcmp7dUGtQdU6o=; b=oCNbGoC3fvjEqW3zRnArsu3XuJrChauIcXAYm5W9Bca04GDNxKffe6NauQKKxzFDJ8 7IqaN5l22BS6YrgXopvEJ4uk7S3zadpCP/7XrOuu2TrZqmLAoqj+iJ5JI0rlwPAAHxak H8RWS0zIQ6UtjSjtevh2H9DXWsUeW25BZfEYUYttUv7li4b5IW2CzGYZ/vgf0XMAqDfE Cjnqwut0Lj+gFMTS0KM/whn21dfa9eQItNdPqh+j7QEyz3c+zb32IvJGAJV4EMQIXnbz V/qPprtVUGtV51YOGW1FRp+RBAU6xoxWIyCP9jzdXqLzSPXAt7s/BVI++RTcMjT3kMBA SpDg== X-Gm-Message-State: AO0yUKXd0VvNJjlwWdX2ZlI5VE+8tXCUjfWSERPj7qcIXIEMJEy8OVev kEaFY2sDi0QiWY6d5v0pdLammkuuTdYsaA== X-Google-Smtp-Source: AK7set/CKzQ71go1j6J3orV9As6wB1/4siy/kbfrACrpf28XZ48so8cgZYbqWR9KwQ57XkBqMSC7fw== X-Received: by 2002:a05:600c:30d2:b0:3e0:c4b:18f5 with SMTP id h18-20020a05600c30d200b003e00c4b18f5mr417027wmn.5.1676416858725; Tue, 14 Feb 2023 15:20:58 -0800 (PST) Received: from bigfoot.. 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[176.36.0.241]) by smtp.gmail.com with ESMTPSA id hg6-20020a05600c538600b003b47b80cec3sm168515wmb.42.2023.02.14.15.20.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Feb 2023 15:20:58 -0800 (PST) From: Eduard Zingerman To: bpf@vger.kernel.org, ast@kernel.org Cc: andrii@kernel.org, daniel@iogearbox.net, martin.lau@linux.dev, kernel-team@fb.com, yhs@fb.com, jose.marchesi@oracle.com, Eduard Zingerman Subject: [PATCH bpf-next v2 3/4] bpf: BPF_ST with variable offset should preserve STACK_ZERO marks Date: Wed, 15 Feb 2023 01:20:29 +0200 Message-Id: <20230214232030.1502829-4-eddyz87@gmail.com> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230214232030.1502829-1-eddyz87@gmail.com> References: <20230214232030.1502829-1-eddyz87@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net BPF_STX instruction preserves STACK_ZERO marks for variable offset writes in situations like below: *(u64*)(r10 - 8) = 0 ; STACK_ZERO marks for fp[-8] r0 = random(-7, -1) ; some random number in range of [-7, -1] r0 += r10 ; r0 is now a variable offset pointer to stack r1 = 0 *(u8*)(r0) = r1 ; BPF_STX writing zero, STACK_ZERO mark for ; fp[-8] is preserved This commit updates verifier.c:check_stack_write_var_off() to process BPF_ST in a similar manner, e.g. the following example: *(u64*)(r10 - 8) = 0 ; STACK_ZERO marks for fp[-8] r0 = random(-7, -1) ; some random number in range of [-7, -1] r0 += r10 ; r0 is now variable offset pointer to stack *(u8*)(r0) = 0 ; BPF_ST writing zero, STACK_ZERO mark for ; fp[-8] is preserved Signed-off-by: Eduard Zingerman --- kernel/bpf/verifier.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index c28afae60874..272563a0b770 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3631,6 +3631,7 @@ static int check_stack_write_var_off(struct bpf_verifier_env *env, int min_off, max_off; int i, err; struct bpf_reg_state *ptr_reg = NULL, *value_reg = NULL; + struct bpf_insn *insn = &env->prog->insnsi[insn_idx]; bool writing_zero = false; /* set if the fact that we're writing a zero is used to let any * stack slots remain STACK_ZERO @@ -3643,7 +3644,8 @@ static int check_stack_write_var_off(struct bpf_verifier_env *env, max_off = ptr_reg->smax_value + off + size; if (value_regno >= 0) value_reg = &cur->regs[value_regno]; - if (value_reg && register_is_null(value_reg)) + if ((value_reg && register_is_null(value_reg)) || + (!value_reg && is_bpf_st_mem(insn) && insn->imm == 0)) writing_zero = true; err = grow_stack_state(state, round_up(-min_off, BPF_REG_SIZE)); From patchwork Tue Feb 14 23:20:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eduard Zingerman X-Patchwork-Id: 13141007 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 650F6C6379F for ; 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[176.36.0.241]) by smtp.gmail.com with ESMTPSA id hg6-20020a05600c538600b003b47b80cec3sm168515wmb.42.2023.02.14.15.20.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Feb 2023 15:20:59 -0800 (PST) From: Eduard Zingerman To: bpf@vger.kernel.org, ast@kernel.org Cc: andrii@kernel.org, daniel@iogearbox.net, martin.lau@linux.dev, kernel-team@fb.com, yhs@fb.com, jose.marchesi@oracle.com, Eduard Zingerman Subject: [PATCH bpf-next v2 4/4] selftests/bpf: check if BPF_ST with variable offset preserves STACK_ZERO Date: Wed, 15 Feb 2023 01:20:30 +0200 Message-Id: <20230214232030.1502829-5-eddyz87@gmail.com> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230214232030.1502829-1-eddyz87@gmail.com> References: <20230214232030.1502829-1-eddyz87@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net A test case to verify that variable offset BPF_ST instruction preserves STACK_ZERO marks when writes zeros, e.g. in the following situation: *(u64*)(r10 - 8) = 0 ; STACK_ZERO marks for fp[-8] r0 = random(-7, -1) ; some random number in range of [-7, -1] r0 += r10 ; r0 is now variable offset pointer to stack *(u8*)(r0) = 0 ; BPF_ST writing zero, STACK_ZERO mark for ; fp[-8] should be preserved. Signed-off-by: Eduard Zingerman --- .../selftests/bpf/verifier/bpf_st_mem.c | 30 +++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/tools/testing/selftests/bpf/verifier/bpf_st_mem.c b/tools/testing/selftests/bpf/verifier/bpf_st_mem.c index 932903f9e585..3af2501082b2 100644 --- a/tools/testing/selftests/bpf/verifier/bpf_st_mem.c +++ b/tools/testing/selftests/bpf/verifier/bpf_st_mem.c @@ -35,3 +35,33 @@ .expected_attach_type = BPF_SK_LOOKUP, .runs = -1, }, +{ + "BPF_ST_MEM stack imm zero, variable offset", + .insns = { + /* set fp[-16], fp[-24] to zeros */ + BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, 0), + BPF_ST_MEM(BPF_DW, BPF_REG_10, -24, 0), + /* r0 = random value in range [-32, -15] */ + BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32), + BPF_JMP_IMM(BPF_JLE, BPF_REG_0, 16, 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + BPF_ALU64_IMM(BPF_SUB, BPF_REG_0, 32), + /* fp[r0] = 0, make a variable offset write of zero, + * this should preserve zero marks on stack. + */ + BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_10), + BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0), + /* r0 = fp[-20], if variable offset write was tracked correctly + * r0 would be a known zero. + */ + BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_10, -20), + /* Would fail return code verification if r0 range is not tracked correctly. */ + BPF_EXIT_INSN(), + }, + .result = ACCEPT, + /* Use prog type that requires return value in range [0, 1] */ + .prog_type = BPF_PROG_TYPE_SK_LOOKUP, + .expected_attach_type = BPF_SK_LOOKUP, + .runs = -1, +},