On 11/2/21 5:10 PM, Andrii Nakryiko wrote:
If BTF is corrupted DATASEC's variable type ID might be incorrect.
Prevent this easy to detect situation with extra NULL check.
Reported by oss-fuzz project.
Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Ack with a nit below.
Acked-by: Yonghong Song <yhs@xxxxxx>
---
tools/lib/bpf/libbpf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 71f5a009010a..4537ce6d54ce 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -2754,7 +2754,7 @@ static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf,
t_var = btf__type_by_id(btf, vsi->type);
var = btf_var(t_var);
Can we move the above 'var = ...' assignment after below if statement?
- if (!btf_is_var(t_var)) {
+ if (!t_var || !btf_is_var(t_var)) {
pr_debug("Non-VAR type seen in section %s\n", name);
return -EINVAL;
}
