diff options
| author | Matt Bobrowski <mattbobrowski@google.com> | 2026-01-13 08:39:47 +0000 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2026-01-13 19:19:13 -0800 |
| commit | f8ade2342e22e7dbc71af496f07c900f8c69dd54 (patch) | |
| tree | f97c5b6717b775ec8bc746bf29203233d8ddc985 /tools | |
| parent | b9da17391e135f65df0eaa73e7c3fd09a1d45f6d (diff) | |
bpf: return PTR_TO_BTF_ID | PTR_TRUSTED from BPF kfuncs by default
Teach the BPF verifier to treat pointers to struct types returned from
BPF kfuncs as implicitly trusted (PTR_TO_BTF_ID | PTR_TRUSTED) by
default. Returning untrusted pointers to struct types from BPF kfuncs
should be considered an exception only, and certainly not the norm.
Update existing selftests to reflect the change in register type
printing (e.g. `ptr_` becoming `trusted_ptr_` in verifier error
messages).
Link: https://lore.kernel.org/bpf/aV4nbCaMfIoM0awM@google.com/
Signed-off-by: Matt Bobrowski <mattbobrowski@google.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20260113083949.2502978-1-mattbobrowski@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools')
4 files changed, 5 insertions, 5 deletions
diff --git a/tools/testing/selftests/bpf/progs/map_kptr_fail.c b/tools/testing/selftests/bpf/progs/map_kptr_fail.c index 4c0ff01f1a96..6443b320c732 100644 --- a/tools/testing/selftests/bpf/progs/map_kptr_fail.c +++ b/tools/testing/selftests/bpf/progs/map_kptr_fail.c @@ -272,7 +272,7 @@ int reject_untrusted_xchg(struct __sk_buff *ctx) SEC("?tc") __failure -__msg("invalid kptr access, R2 type=ptr_prog_test_ref_kfunc expected=ptr_prog_test_member") +__msg("invalid kptr access, R2 type=trusted_ptr_prog_test_ref_kfunc expected=ptr_prog_test_member") int reject_bad_type_xchg(struct __sk_buff *ctx) { struct prog_test_ref_kfunc *ref_ptr; @@ -291,7 +291,7 @@ int reject_bad_type_xchg(struct __sk_buff *ctx) } SEC("?tc") -__failure __msg("invalid kptr access, R2 type=ptr_prog_test_ref_kfunc") +__failure __msg("invalid kptr access, R2 type=trusted_ptr_prog_test_ref_kfunc") int reject_member_of_ref_xchg(struct __sk_buff *ctx) { struct prog_test_ref_kfunc *ref_ptr; diff --git a/tools/testing/selftests/bpf/progs/struct_ops_kptr_return_fail__wrong_type.c b/tools/testing/selftests/bpf/progs/struct_ops_kptr_return_fail__wrong_type.c index 6a2dd5367802..c8d217e89eea 100644 --- a/tools/testing/selftests/bpf/progs/struct_ops_kptr_return_fail__wrong_type.c +++ b/tools/testing/selftests/bpf/progs/struct_ops_kptr_return_fail__wrong_type.c @@ -12,7 +12,7 @@ void bpf_task_release(struct task_struct *p) __ksym; * reject programs returning a referenced kptr of the wrong type. */ SEC("struct_ops/test_return_ref_kptr") -__failure __msg("At program exit the register R0 is not a known value (ptr_or_null_)") +__failure __msg("At program exit the register R0 is not a known value (trusted_ptr_or_null_)") struct task_struct *BPF_PROG(kptr_return_fail__wrong_type, int dummy, struct task_struct *task, struct cgroup *cgrp) { diff --git a/tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c b/tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c index 1204fbc58178..e7dae0cf9c17 100644 --- a/tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c +++ b/tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c @@ -72,7 +72,7 @@ int trusted_task_arg_nonnull_fail1(void *ctx) SEC("?tp_btf/task_newtask") __failure __log_level(2) -__msg("R1 type=ptr_or_null_ expected=ptr_, trusted_ptr_, rcu_ptr_") +__msg("R1 type=trusted_ptr_or_null_ expected=ptr_, trusted_ptr_, rcu_ptr_") __msg("Caller passes invalid args into func#1 ('subprog_trusted_task_nonnull')") int trusted_task_arg_nonnull_fail2(void *ctx) { diff --git a/tools/testing/selftests/bpf/verifier/calls.c b/tools/testing/selftests/bpf/verifier/calls.c index c8d640802cce..9ca83dce100d 100644 --- a/tools/testing/selftests/bpf/verifier/calls.c +++ b/tools/testing/selftests/bpf/verifier/calls.c @@ -220,7 +220,7 @@ }, .result_unpriv = REJECT, .result = REJECT, - .errstr = "variable ptr_ access var_off=(0x0; 0x7) disallowed", + .errstr = "variable trusted_ptr_ access var_off=(0x0; 0x7) disallowed", }, { "calls: invalid kfunc call: referenced arg needs refcounted PTR_TO_BTF_ID", |