[PATCH 1/2] bpf: btf: silence uninitialize variable warnings

From: Dan Carpenter
Date: Fri Apr 27 2018 - 11:05:29 EST


Smatch complains that size can be uninitialized if btf_type_id_size()
returns NULL. It seems reasonable enough to check for that.

Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
This goes to the BPF tree (linux-next).

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 22e1046a1a86..e631b6fd60d3 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -1229,7 +1229,8 @@ static int btf_array_check_member(struct btf_verifier_env *env,
}

array_type_id = member->type;
- btf_type_id_size(btf, &array_type_id, &array_size);
+ if (!btf_type_id_size(btf, &array_type_id, &array_size))
+ return -EINVAL;
struct_size = struct_type->size;
bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off);
if (struct_size - bytes_offset < array_size) {
@@ -1351,6 +1352,8 @@ static void btf_array_seq_show(const struct btf *btf, const struct btf_type *t,

elem_type_id = array->type;
elem_type = btf_type_id_size(btf, &elem_type_id, &elem_size);
+ if (!elem_type)
+ return;
elem_ops = btf_type_ops(elem_type);
seq_puts(m, "[");
for (i = 0; i < array->nelems; i++) {