[PATCH 1/5] bpf: Allow non struct type for btf ctx access
From: Jiri Olsa <jolsa@kernel.org>
Date: 2019-12-29 14:37:53
Also in:
bpf
Subsystem:
bpf [btf], bpf [general] (safe dynamic programs and tools), the rest · Maintainers:
Martin KaFai Lau, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Linus Torvalds
I'm not sure why the restriction was added, but I can't access pointers to POD types like const char * when probing vfs_read function. Removing the check and allow non struct type access in context. Signed-off-by: Jiri Olsa <jolsa@kernel.org> --- kernel/bpf/btf.c | 6 ------ 1 file changed, 6 deletions(-)
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index ed2075884724..ae90f60ac1b8 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c@@ -3712,12 +3712,6 @@ bool btf_ctx_access(int off, int size, enum bpf_access_type type, /* skip modifiers */ while (btf_type_is_modifier(t)) t = btf_type_by_id(btf, t->type); - if (!btf_type_is_struct(t)) { - bpf_log(log, - "func '%s' arg%d type %s is not a struct\n", - tname, arg, btf_kind_str[BTF_INFO_KIND(t->info)]); - return false; - } bpf_log(log, "func '%s' arg%d has btf_id %d type %s '%s'\n", tname, arg, info->btf_id, btf_kind_str[BTF_INFO_KIND(t->info)], __btf_name_by_offset(btf, t->name_off));
--
2.21.1