[PATCH v2 2/3] NFC: Fix possible memory corruption when handling SHDLC I-Frame commands

From: Amit Pundir
Date: Wed May 02 2018 - 13:48:33 EST


From: Suren Baghdasaryan <surenb@xxxxxxxxxx>

When handling SHDLC I-Frame commands "pipe" field used for indexing
into an array should be checked before usage. If left unchecked it
might access memory outside of the array of size NFC_HCI_MAX_PIPES(127).

Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Signed-off-by: Amit Pundir <amit.pundir@xxxxxxxxxx>
---
v2:
Resend. No changes.

net/nfc/hci/core.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/net/nfc/hci/core.c b/net/nfc/hci/core.c
index ac8030c4..19cb2e4 100644
--- a/net/nfc/hci/core.c
+++ b/net/nfc/hci/core.c
@@ -209,6 +209,11 @@ void nfc_hci_cmd_received(struct nfc_hci_dev *hdev, u8 pipe, u8 cmd,
}
create_info = (struct hci_create_pipe_resp *)skb->data;

+ if (create_info->pipe >= NFC_HCI_MAX_PIPES) {
+ status = NFC_HCI_ANY_E_NOK;
+ goto exit;
+ }
+
/* Save the new created pipe and bind with local gate,
* the description for skb->data[3] is destination gate id
* but since we received this cmd from host controller, we
@@ -232,6 +237,11 @@ void nfc_hci_cmd_received(struct nfc_hci_dev *hdev, u8 pipe, u8 cmd,
}
delete_info = (struct hci_delete_pipe_noti *)skb->data;

+ if (delete_info->pipe >= NFC_HCI_MAX_PIPES) {
+ status = NFC_HCI_ANY_E_NOK;
+ goto exit;
+ }
+
hdev->pipes[delete_info->pipe].gate = NFC_HCI_INVALID_GATE;
hdev->pipes[delete_info->pipe].dest_host = NFC_HCI_INVALID_HOST;
break;
--
2.7.4