diff options
author | Yonghong Song | 2020-05-13 11:02:21 -0700 |
---|---|---|
committer | Alexei Starovoitov | 2020-05-13 12:30:50 -0700 |
commit | 3c32cc1bceba8a1755dc35cd97516f6c67856844 (patch) | |
tree | 10e978c4bc1374703070d8ecee9e4e007b13183b /kernel/bpf/map_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/map_iter.c')
-rw-r--r-- | kernel/bpf/map_iter.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/bpf/map_iter.c b/kernel/bpf/map_iter.c index c6216a5fe56e..c69071e334bf 100644 --- a/kernel/bpf/map_iter.c +++ b/kernel/bpf/map_iter.c @@ -87,6 +87,11 @@ static const struct bpf_iter_reg bpf_map_reg_info = { .init_seq_private = NULL, .fini_seq_private = NULL, .seq_priv_size = sizeof(struct bpf_iter_seq_map_info), + .ctx_arg_info_size = 1, + .ctx_arg_info = { + { offsetof(struct bpf_iter__bpf_map, map), + PTR_TO_BTF_ID_OR_NULL }, + }, }; static int __init bpf_map_iter_init(void) |