Bluetooth: hci_uart: Check if socket buffer is ERR_PTR in h4_recv_buf()

h4_recv_buf() callers store the return value to socket buffer and
recursively pass the buffer to h4_recv_buf() without protection. So,
ERR_PTR returned from h4_recv_buf() can be dereferenced, if called again
before setting the socket buffer to NULL from previous error. Check if
skb is ERR_PTR in h4_recv_buf().

Reported-by: syzbot+017a32f149406df32703@syzkaller.appspotmail.com
Signed-off-by: Myungho Jung <mhjungk@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
Myungho Jung 2019-01-22 00:33:26 -08:00 committed by Marcel Holtmann
parent 37c589ec28
commit 1dc2d78515
2 changed files with 8 additions and 0 deletions

View file

@ -60,6 +60,10 @@ static inline struct sk_buff *h4_recv_buf(struct hci_dev *hdev,
const struct h4_recv_pkt *pkts,
int pkts_count)
{
/* Check for error from previous call */
if (IS_ERR(skb))
skb = NULL;
while (count) {
int i, len;

View file

@ -174,6 +174,10 @@ struct sk_buff *h4_recv_buf(struct hci_dev *hdev, struct sk_buff *skb,
struct hci_uart *hu = hci_get_drvdata(hdev);
u8 alignment = hu->alignment ? hu->alignment : 1;
/* Check for error from previous call */
if (IS_ERR(skb))
skb = NULL;
while (count) {
int i, len;