diff options
| author | Yonghong Song <yhs@fb.com> | 2020-05-13 11:02:21 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2020-05-13 12:30:50 -0700 |
| commit | 3c32cc1bceba8a1755dc35cd97516f6c67856844 (patch) | |
| tree | 10e978c4bc1374703070d8ecee9e4e007b13183b /kernel/bpf/task_iter.c | |
| parent | ab2ee4fcb9d61fd57db70db694adbcf54662bd80 (diff) | |
bpf: Enable bpf_iter targets registering ctx argument types
Commit b121b341e598 ("bpf: Add PTR_TO_BTF_ID_OR_NULL
support") adds a field btf_id_or_null_non0_off to
bpf_prog->aux structure to indicate that the
first ctx argument is PTR_TO_BTF_ID reg_type and
all others are PTR_TO_BTF_ID_OR_NULL.
This approach does not really scale if we have
other different reg types in the future, e.g.,
a pointer to a buffer.
This patch enables bpf_iter targets registering ctx argument
reg types which may be different from the default one.
For example, for pointers to structures, the default reg_type
is PTR_TO_BTF_ID for tracing program. The target can register
a particular pointer type as PTR_TO_BTF_ID_OR_NULL which can
be used by the verifier to enforce accesses.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200513180221.2949882-1-yhs@fb.com
Diffstat (limited to 'kernel/bpf/task_iter.c')
| -rw-r--r-- | kernel/bpf/task_iter.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/kernel/bpf/task_iter.c b/kernel/bpf/task_iter.c index bd7bfd83d9e0..a9b7264dda08 100644 --- a/kernel/bpf/task_iter.c +++ b/kernel/bpf/task_iter.c @@ -312,6 +312,11 @@ static const struct bpf_iter_reg task_reg_info = { .init_seq_private = init_seq_pidns, .fini_seq_private = fini_seq_pidns, .seq_priv_size = sizeof(struct bpf_iter_seq_task_info), + .ctx_arg_info_size = 1, + .ctx_arg_info = { + { offsetof(struct bpf_iter__task, task), + PTR_TO_BTF_ID_OR_NULL }, + }, }; static const struct bpf_iter_reg task_file_reg_info = { @@ -320,6 +325,13 @@ static const struct bpf_iter_reg task_file_reg_info = { .init_seq_private = init_seq_pidns, .fini_seq_private = fini_seq_pidns, .seq_priv_size = sizeof(struct bpf_iter_seq_task_file_info), + .ctx_arg_info_size = 2, + .ctx_arg_info = { + { offsetof(struct bpf_iter__task_file, task), + PTR_TO_BTF_ID_OR_NULL }, + { offsetof(struct bpf_iter__task_file, file), + PTR_TO_BTF_ID_OR_NULL }, + }, }; static int __init task_iter_init(void) |