xhci: check control context is valid before dereferencing it.

[ Upstream commit 597899d2f7c5619c87185ee7953d004bd37fd0eb ]

Don't dereference ctrl_ctx before checking it's valid.
Issue reported by Klockwork

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210406070208.3406266-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 6c508d0313f7fcaa9b671861b7da4312a8e02d9a..fc07d68fdd15401cb345466108f29bea05f9083a 100644 (file)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -3148,6 +3148,14 @@ static void xhci_endpoint_reset(struct usb_hcd *hcd,
 
        /* config ep command clears toggle if add and drop ep flags are set */
        ctrl_ctx = xhci_get_input_control_ctx(cfg_cmd->in_ctx);
+       if (!ctrl_ctx) {
+               spin_unlock_irqrestore(&xhci->lock, flags);
+               xhci_free_command(xhci, cfg_cmd);
+               xhci_warn(xhci, "%s: Could not get input context, bad type.\n",
+                               __func__);
+               goto cleanup;
+       }
+
        xhci_setup_input_ctx_for_config_ep(xhci, cfg_cmd->in_ctx, vdev->out_ctx,
                                           ctrl_ctx, ep_flag, ep_flag);
        xhci_endpoint_copy(xhci, cfg_cmd->in_ctx, vdev->out_ctx, ep_index);