From: Kumar Kartikeya Dwivedi memxor@gmail.com

[ Upstream commit bd74e238ae6944b462f57ce8752440a011ba4530 ]

Andrii spotted that process_dynptr_func's rejection of incorrect argument register type will print an error string where argument numbers are not zero-indexed, unlike elsewhere in the verifier. Fix this by subtracting 1 from regno. The same scenario exists for iterator messages. Fix selftest error strings that match on the exact argument number while we're at it to ensure clean bisection.

Suggested-by: Andrii Nakryiko andrii@kernel.org Signed-off-by: Kumar Kartikeya Dwivedi memxor@gmail.com Link: https://lore.kernel.org/r/20241203002235.3776418-1-memxor@gmail.com Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/bpf/verifier.c | 12 +++++----- .../testing/selftests/bpf/progs/dynptr_fail.c | 22 +++++++++---------- .../selftests/bpf/progs/iters_state_safety.c | 14 ++++++------ .../selftests/bpf/progs/iters_testmod_seq.c | 4 ++-- .../bpf/progs/test_kfunc_dynptr_param.c | 2 +- .../selftests/bpf/progs/verifier_bits_iter.c | 4 ++-- 6 files changed, 29 insertions(+), 29 deletions(-)

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 91317857ea3ee..436a83784b7d2 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -7903,7 +7903,7 @@ static int process_dynptr_func(struct bpf_verifier_env *env, int regno, int insn if (reg->type != PTR_TO_STACK && reg->type != CONST_PTR_TO_DYNPTR) { verbose(env, "arg#%d expected pointer to stack or const struct bpf_dynptr\n", - regno); + regno - 1); return -EINVAL; }

@@ -7957,7 +7957,7 @@ static int process_dynptr_func(struct bpf_verifier_env *env, int regno, int insn if (!is_dynptr_reg_valid_init(env, reg)) { verbose(env, "Expected an initialized dynptr as arg #%d\n", - regno); + regno - 1); return -EINVAL; }

@@ -7965,7 +7965,7 @@ static int process_dynptr_func(struct bpf_verifier_env *env, int regno, int insn if (!is_dynptr_type_expected(env, reg, arg_type & ~MEM_RDONLY)) { verbose(env, "Expected a dynptr of type %s as arg #%d\n", - dynptr_type_str(arg_to_dynptr_type(arg_type)), regno); + dynptr_type_str(arg_to_dynptr_type(arg_type)), regno - 1); return -EINVAL; }

@@ -8029,7 +8029,7 @@ static int process_iter_arg(struct bpf_verifier_env *env, int regno, int insn_id */ btf_id = btf_check_iter_arg(meta->btf, meta->func_proto, regno - 1); if (btf_id < 0) { - verbose(env, "expected valid iter pointer as arg #%d\n", regno); + verbose(env, "expected valid iter pointer as arg #%d\n", regno - 1); return -EINVAL; } t = btf_type_by_id(meta->btf, btf_id); @@ -8039,7 +8039,7 @@ static int process_iter_arg(struct bpf_verifier_env *env, int regno, int insn_id /* bpf_iter_<type>_new() expects pointer to uninit iter state */ if (!is_iter_reg_valid_uninit(env, reg, nr_slots)) { verbose(env, "expected uninitialized iter_%s as arg #%d\n", - iter_type_str(meta->btf, btf_id), regno); + iter_type_str(meta->btf, btf_id), regno - 1); return -EINVAL; }

@@ -8063,7 +8063,7 @@ static int process_iter_arg(struct bpf_verifier_env *env, int regno, int insn_id break; case -EINVAL: verbose(env, "expected an initialized iter_%s as arg #%d\n", - iter_type_str(meta->btf, btf_id), regno); + iter_type_str(meta->btf, btf_id), regno - 1); return err; case -EPROTO: verbose(env, "expected an RCU CS when using %s\n", meta->func_name); diff --git a/tools/testing/selftests/bpf/progs/dynptr_fail.c b/tools/testing/selftests/bpf/progs/dynptr_fail.c index 8f36c9de75915..dfd817d0348c4 100644 --- a/tools/testing/selftests/bpf/progs/dynptr_fail.c +++ b/tools/testing/selftests/bpf/progs/dynptr_fail.c @@ -149,7 +149,7 @@ int ringbuf_release_uninit_dynptr(void *ctx)

/* A dynptr can't be used after it has been invalidated */ SEC("?raw_tp") -__failure __msg("Expected an initialized dynptr as arg #3") +__failure __msg("Expected an initialized dynptr as arg #2") int use_after_invalid(void *ctx) { struct bpf_dynptr ptr; @@ -428,7 +428,7 @@ int invalid_helper2(void *ctx)

/* A bpf_dynptr is invalidated if it's been written into */ SEC("?raw_tp") -__failure __msg("Expected an initialized dynptr as arg #1") +__failure __msg("Expected an initialized dynptr as arg #0") int invalid_write1(void *ctx) { struct bpf_dynptr ptr; @@ -1407,7 +1407,7 @@ int invalid_slice_rdwr_rdonly(struct __sk_buff *skb)

/* bpf_dynptr_adjust can only be called on initialized dynptrs */ SEC("?raw_tp") -__failure __msg("Expected an initialized dynptr as arg #1") +__failure __msg("Expected an initialized dynptr as arg #0") int dynptr_adjust_invalid(void *ctx) { struct bpf_dynptr ptr = {}; @@ -1420,7 +1420,7 @@ int dynptr_adjust_invalid(void *ctx)

/* bpf_dynptr_is_null can only be called on initialized dynptrs */ SEC("?raw_tp") -__failure __msg("Expected an initialized dynptr as arg #1") +__failure __msg("Expected an initialized dynptr as arg #0") int dynptr_is_null_invalid(void *ctx) { struct bpf_dynptr ptr = {}; @@ -1433,7 +1433,7 @@ int dynptr_is_null_invalid(void *ctx)

/* bpf_dynptr_is_rdonly can only be called on initialized dynptrs */ SEC("?raw_tp") -__failure __msg("Expected an initialized dynptr as arg #1") +__failure __msg("Expected an initialized dynptr as arg #0") int dynptr_is_rdonly_invalid(void *ctx) { struct bpf_dynptr ptr = {}; @@ -1446,7 +1446,7 @@ int dynptr_is_rdonly_invalid(void *ctx)

/* bpf_dynptr_size can only be called on initialized dynptrs */ SEC("?raw_tp") -__failure __msg("Expected an initialized dynptr as arg #1") +__failure __msg("Expected an initialized dynptr as arg #0") int dynptr_size_invalid(void *ctx) { struct bpf_dynptr ptr = {}; @@ -1459,7 +1459,7 @@ int dynptr_size_invalid(void *ctx)

/* Only initialized dynptrs can be cloned */ SEC("?raw_tp") -__failure __msg("Expected an initialized dynptr as arg #1") +__failure __msg("Expected an initialized dynptr as arg #0") int clone_invalid1(void *ctx) { struct bpf_dynptr ptr1 = {}; @@ -1493,7 +1493,7 @@ int clone_invalid2(struct xdp_md *xdp)

/* Invalidating a dynptr should invalidate its clones */ SEC("?raw_tp") -__failure __msg("Expected an initialized dynptr as arg #3") +__failure __msg("Expected an initialized dynptr as arg #2") int clone_invalidate1(void *ctx) { struct bpf_dynptr clone; @@ -1514,7 +1514,7 @@ int clone_invalidate1(void *ctx)

/* Invalidating a dynptr should invalidate its parent */ SEC("?raw_tp") -__failure __msg("Expected an initialized dynptr as arg #3") +__failure __msg("Expected an initialized dynptr as arg #2") int clone_invalidate2(void *ctx) { struct bpf_dynptr ptr; @@ -1535,7 +1535,7 @@ int clone_invalidate2(void *ctx)

/* Invalidating a dynptr should invalidate its siblings */ SEC("?raw_tp") -__failure __msg("Expected an initialized dynptr as arg #3") +__failure __msg("Expected an initialized dynptr as arg #2") int clone_invalidate3(void *ctx) { struct bpf_dynptr ptr; @@ -1723,7 +1723,7 @@ __noinline long global_call_bpf_dynptr(const struct bpf_dynptr *dynptr) }

SEC("?raw_tp") -__failure __msg("arg#1 expected pointer to stack or const struct bpf_dynptr") +__failure __msg("arg#0 expected pointer to stack or const struct bpf_dynptr") int test_dynptr_reg_type(void *ctx) { struct task_struct *current = NULL; diff --git a/tools/testing/selftests/bpf/progs/iters_state_safety.c b/tools/testing/selftests/bpf/progs/iters_state_safety.c index d47e59aba6de3..f41257eadbb25 100644 --- a/tools/testing/selftests/bpf/progs/iters_state_safety.c +++ b/tools/testing/selftests/bpf/progs/iters_state_safety.c @@ -73,7 +73,7 @@ int create_and_forget_to_destroy_fail(void *ctx) }

SEC("?raw_tp") -__failure __msg("expected an initialized iter_num as arg #1") +__failure __msg("expected an initialized iter_num as arg #0") int destroy_without_creating_fail(void *ctx) { /* init with zeros to stop verifier complaining about uninit stack */ @@ -91,7 +91,7 @@ int destroy_without_creating_fail(void *ctx) }

SEC("?raw_tp") -__failure __msg("expected an initialized iter_num as arg #1") +__failure __msg("expected an initialized iter_num as arg #0") int compromise_iter_w_direct_write_fail(void *ctx) { struct bpf_iter_num iter; @@ -143,7 +143,7 @@ int compromise_iter_w_direct_write_and_skip_destroy_fail(void *ctx) }

SEC("?raw_tp") -__failure __msg("expected an initialized iter_num as arg #1") +__failure __msg("expected an initialized iter_num as arg #0") int compromise_iter_w_helper_write_fail(void *ctx) { struct bpf_iter_num iter; @@ -230,7 +230,7 @@ int valid_stack_reuse(void *ctx) }

SEC("?raw_tp") -__failure __msg("expected uninitialized iter_num as arg #1") +__failure __msg("expected uninitialized iter_num as arg #0") int double_create_fail(void *ctx) { struct bpf_iter_num iter; @@ -258,7 +258,7 @@ int double_create_fail(void *ctx) }

SEC("?raw_tp") -__failure __msg("expected an initialized iter_num as arg #1") +__failure __msg("expected an initialized iter_num as arg #0") int double_destroy_fail(void *ctx) { struct bpf_iter_num iter; @@ -284,7 +284,7 @@ int double_destroy_fail(void *ctx) }

SEC("?raw_tp") -__failure __msg("expected an initialized iter_num as arg #1") +__failure __msg("expected an initialized iter_num as arg #0") int next_without_new_fail(void *ctx) { struct bpf_iter_num iter; @@ -305,7 +305,7 @@ int next_without_new_fail(void *ctx) }

SEC("?raw_tp") -__failure __msg("expected an initialized iter_num as arg #1") +__failure __msg("expected an initialized iter_num as arg #0") int next_after_destroy_fail(void *ctx) { struct bpf_iter_num iter; diff --git a/tools/testing/selftests/bpf/progs/iters_testmod_seq.c b/tools/testing/selftests/bpf/progs/iters_testmod_seq.c index 4a176e6aede89..6543d5b6e0a97 100644 --- a/tools/testing/selftests/bpf/progs/iters_testmod_seq.c +++ b/tools/testing/selftests/bpf/progs/iters_testmod_seq.c @@ -79,7 +79,7 @@ int testmod_seq_truncated(const void *ctx)

SEC("?raw_tp") __failure -__msg("expected an initialized iter_testmod_seq as arg #2") +__msg("expected an initialized iter_testmod_seq as arg #1") int testmod_seq_getter_before_bad(const void *ctx) { struct bpf_iter_testmod_seq it; @@ -89,7 +89,7 @@ int testmod_seq_getter_before_bad(const void *ctx)

SEC("?raw_tp") __failure -__msg("expected an initialized iter_testmod_seq as arg #2") +__msg("expected an initialized iter_testmod_seq as arg #1") int testmod_seq_getter_after_bad(const void *ctx) { struct bpf_iter_testmod_seq it; diff --git a/tools/testing/selftests/bpf/progs/test_kfunc_dynptr_param.c b/tools/testing/selftests/bpf/progs/test_kfunc_dynptr_param.c index e68667aec6a65..cd4d752bd089c 100644 --- a/tools/testing/selftests/bpf/progs/test_kfunc_dynptr_param.c +++ b/tools/testing/selftests/bpf/progs/test_kfunc_dynptr_param.c @@ -45,7 +45,7 @@ int BPF_PROG(not_valid_dynptr, int cmd, union bpf_attr *attr, unsigned int size) }

SEC("?lsm.s/bpf") -__failure __msg("arg#1 expected pointer to stack or const struct bpf_dynptr") +__failure __msg("arg#0 expected pointer to stack or const struct bpf_dynptr") int BPF_PROG(not_ptr_to_stack, int cmd, union bpf_attr *attr, unsigned int size) { unsigned long val = 0; diff --git a/tools/testing/selftests/bpf/progs/verifier_bits_iter.c b/tools/testing/selftests/bpf/progs/verifier_bits_iter.c index 7c881bca9af5c..497febf5c578d 100644 --- a/tools/testing/selftests/bpf/progs/verifier_bits_iter.c +++ b/tools/testing/selftests/bpf/progs/verifier_bits_iter.c @@ -32,7 +32,7 @@ int BPF_PROG(no_destroy, struct bpf_iter_meta *meta, struct cgroup *cgrp)

SEC("iter/cgroup") __description("uninitialized iter in ->next()") -__failure __msg("expected an initialized iter_bits as arg #1") +__failure __msg("expected an initialized iter_bits as arg #0") int BPF_PROG(next_uninit, struct bpf_iter_meta *meta, struct cgroup *cgrp) { struct bpf_iter_bits *it = NULL; @@ -43,7 +43,7 @@ int BPF_PROG(next_uninit, struct bpf_iter_meta *meta, struct cgroup *cgrp)

SEC("iter/cgroup") __description("uninitialized iter in ->destroy()") -__failure __msg("expected an initialized iter_bits as arg #1") +__failure __msg("expected an initialized iter_bits as arg #0") int BPF_PROG(destroy_uninit, struct bpf_iter_meta *meta, struct cgroup *cgrp) { struct bpf_iter_bits it = {};