Merge tag 'v4.14.73' into linux-linaro-lsk-v4.14lsk-v4.14-18.09

This is the 4.14.73 stable release

# gpg: Signature made Sat 29 Sep 2018 11:06:11 BST
# gpg:                using RSA key 647F28654894E3BD457199BE38DBBDC86092693E
# gpg: Good signature from "Greg Kroah-Hartman <gregkh@linuxfoundation.org>" [unknown]
# gpg:                 aka "Greg Kroah-Hartman (Linux kernel stable release signing key) <greg@kroah.com>" [unknown]
# gpg:                 aka "Greg Kroah-Hartman <gregkh@kernel.org>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 647F 2865 4894 E3BD 4571  99BE 38DB BDC8 6092 693E

1 files changed, 30 insertions, 0 deletions

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 6b11fd9d8efe..64ddba3f79a9 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -47,6 +47,21 @@ static unsigned int quirks;
 module_param(quirks, uint, S_IRUGO);
 MODULE_PARM_DESC(quirks, "Bit flags for quirks to be enabled as default");
 
+static bool td_on_ring(struct xhci_td *td, struct xhci_ring *ring)
+{
+	struct xhci_segment *seg = ring->first_seg;
+
+	if (!td || !td->start_seg)
+		return false;
+	do {
+		if (seg == td->start_seg)
+			return true;
+		seg = seg->next;
+	} while (seg && seg != ring->first_seg);
+
+	return false;
+}
+
 /* TODO: copied from ehci-hcd.c - can this be refactored? */
 /*
  * xhci_handshake - spin reading hc until handshake completes or fails
@@ -1511,6 +1526,21 @@ static int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 		goto done;
 	}
 
+	/*
+	 * check ring is not re-allocated since URB was enqueued. If it is, then
+	 * make sure none of the ring related pointers in this URB private data
+	 * are touched, such as td_list, otherwise we overwrite freed data
+	 */
+	if (!td_on_ring(&urb_priv->td[0], ep_ring)) {
+		xhci_err(xhci, "Canceled URB td not found on endpoint ring");
+		for (i = urb_priv->num_tds_done; i < urb_priv->num_tds; i++) {
+			td = &urb_priv->td[i];
+			if (!list_empty(&td->cancelled_td_list))
+				list_del_init(&td->cancelled_td_list);
+		}
+		goto err_giveback;
+	}
+
 	if (xhci->xhc_state & XHCI_STATE_HALTED) {
 		xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
 				"HC halted, freeing TD manually.");