From e0867b521017d4654cccfaa381b19d85139e632b Mon Sep 17 00:00:00 2001 From: Hemant Kumar Date: Thu, 14 Jun 2018 17:58:58 -0700 Subject: [PATCH] xhci: Fix use-after-free in xhci_free_virt_device KASAN found a use-after-free in xhci_free_virt_device+0x33b/0x38e where xhci_free_virt_device() sets slot id to 0 if udev exists: if (dev->udev && dev->udev->slot_id) dev->udev->slot_id = 0; dev->udev will be true even if udev is freed because dev->udev is not set to NULL. set dev->udev pointer to NULL in xhci_free_dev() The original patch went to stable so this fix needs to be applied there as well. Fixes: a400efe455f7 ("xhci: zero usb device slot_id member when disabling and freeing a xhci slot") Cc: Reported-by: Guenter Roeck Reviewed-by: Guenter Roeck Tested-by: Guenter Roeck Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman Git-commit: 44a182b9d17765514fa2b1cc911e4e65134eef93 Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git [hemantk@codeaurora.org: resolved merge conflict] Signed-off-by: Hemant Kumar Change-Id: I507d8439de007b3df6728f77407a4aee51463913 --- drivers/usb/host/xhci.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 4954e22a421b..50a1b0a34617 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -3659,6 +3659,7 @@ void xhci_free_dev(struct usb_hcd *hcd, struct usb_device *udev) del_timer_sync(&virt_dev->eps[i].stop_cmd_timer); } + virt_dev->udev = NULL; spin_lock_irqsave(&xhci->lock, flags); /* Don't disable the slot if the host controller is dead. */ state = readl(&xhci->op_regs->status);