From: Martin KaFai Lau <kafai@xxxxxx>
[ Upstream commit 4b1c5d917d34f705096bb7dd8a2bd19b0881970e ]
The end boundary math for type section is incorrect in
btf_check_all_metas(). It just happens that hdr->type_off
is always 0 for now because there are only two sections
(type and string) and string section must be at the end (ensured
in btf_parse_str_sec).
However, type_off may not be 0 if a new section would be added later.
This patch fixes it.
Fixes: f80442a4cd18 ("bpf: btf: Change how section is supported in btf_header")
Reported-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Signed-off-by: Martin KaFai Lau <kafai@xxxxxx>
Acked-by: Yonghong Song <yhs@xxxxxx>
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
kernel/bpf/btf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 2590700237c1..138f0302692e 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -1844,7 +1844,7 @@ static int btf_check_all_metas(struct btf_verifier_env *env)
hdr = &btf->hdr;
cur = btf->nohdr_data + hdr->type_off;
- end = btf->nohdr_data + hdr->type_len;
+ end = cur + hdr->type_len;
env->log_type_id = 1;
while (cur < end) {
--
2.17.1
