From: Mathias Nyman mathias.nyman@linux.intel.com

commit 03ed579d9d51aa018830b0de3e8b463faf6b87db upstream.

Check that the xhci_virt_dev structure that we dug out based on a slot_id value from a command completion is valid before dereferencing it.

Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Link: https://lore.kernel.org/r/20210129130044.206855-7-mathias.nyman@linux.intel.... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Roman Smirnov r.smirnov@omp.ru --- drivers/usb/host/xhci-ring.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index fbb7a5b51ef4..a769803e7d38 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1415,6 +1415,8 @@ static void xhci_handle_cmd_config_ep(struct xhci_hcd *xhci, int slot_id, * is not waiting on the configure endpoint command. */ virt_dev = xhci->devs[slot_id]; + if (!virt_dev) + return; ctrl_ctx = xhci_get_input_control_ctx(virt_dev->in_ctx); if (!ctrl_ctx) { xhci_warn(xhci, "Could not get input context, bad type.\n"); @@ -1459,6 +1461,8 @@ static void xhci_handle_cmd_addr_dev(struct xhci_hcd *xhci, int slot_id) struct xhci_slot_ctx *slot_ctx;

vdev = xhci->devs[slot_id]; + if (!vdev) + return; slot_ctx = xhci_get_slot_ctx(xhci, vdev->out_ctx); trace_xhci_handle_cmd_addr_dev(slot_ctx); } @@ -1470,13 +1474,15 @@ static void xhci_handle_cmd_reset_dev(struct xhci_hcd *xhci, int slot_id, struct xhci_slot_ctx *slot_ctx;

vdev = xhci->devs[slot_id]; + if (!vdev) { + xhci_warn(xhci, "Reset device command completion for disabled slot %u\n", + slot_id); + return; + } slot_ctx = xhci_get_slot_ctx(xhci, vdev->out_ctx); trace_xhci_handle_cmd_reset_dev(slot_ctx);

xhci_dbg(xhci, "Completed reset device command.\n"); - if (!xhci->devs[slot_id]) - xhci_warn(xhci, "Reset device command completion " - "for disabled slot %u\n", slot_id); }

static void xhci_handle_cmd_nec_get_fw(struct xhci_hcd *xhci,