Check upon `num_rsp` is insufficient. A malformed event packet with a
large `num_rsp` number makes hci_extended_inquiry_result_evt() go out
of bounds. Fix it.
This patch fixes the following syzbot bug:
https://syzkaller.appspot.com/bug?id=4bf11aa05c4ca51ce0df86e500fce486552dc8d2
Reported-by: syzbot+d8489a79b781849b9c46@xxxxxxxxxxxxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Peilin Ye <yepeilin.cs@xxxxxxxxx>
---
Change in v3:
- Minimum `skb->len` requirement was 1 byte inaccurate since `info`
starts from `skb->data + 1`. Fix it.
Changes in v2:
- Use `skb->len` instead of `skb->truesize` as the length limit.
- Leave `num_rsp` as of type `int`.
net/bluetooth/hci_event.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 03a0759f2fc2..13d8802b8137 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -4375,7 +4375,7 @@ static void hci_extended_inquiry_result_evt(struct hci_dev *hdev,
BT_DBG("%s num_rsp %d", hdev->name, num_rsp);
- if (!num_rsp)
+ if (!num_rsp || skb->len < num_rsp * sizeof(*info) + 1)
return;
if (hci_dev_test_flag(hdev, HCI_PERIODIC_INQ))
--
2.25.1
