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authorMathias Nyman <mathias.nyman@linux.intel.com>2019-10-04 13:59:33 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-10-04 14:32:12 +0200
commitcfbb8a84c2d2ef49bccacb511002bca4f6053555 (patch)
tree9d1026266cf639881ec85127cc7a4585a239d85a /drivers/usb
parentxhci: Increase STS_SAVE timeout in xhci_suspend() (diff)
downloadlinux-cfbb8a84c2d2ef49bccacb511002bca4f6053555.tar.xz
linux-cfbb8a84c2d2ef49bccacb511002bca4f6053555.zip
xhci: Fix NULL pointer dereference in xhci_clear_tt_buffer_complete()
udev stored in ep->hcpriv might be NULL if tt buffer is cleared due to a halted control endpoint during device enumeration xhci_clear_tt_buffer_complete is called by hub_tt_work() once it's scheduled, and by then usb core might have freed and allocated a new udev for the next enumeration attempt. Fixes: ef513be0a905 ("usb: xhci: Add Clear_TT_Buffer") Cc: <stable@vger.kernel.org> # v5.3 Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/1570190373-30684-9-git-send-email-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb')
-rw-r--r--drivers/usb/host/xhci.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 00f3804f7aa7..517ec3206f6e 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -5238,8 +5238,16 @@ static void xhci_clear_tt_buffer_complete(struct usb_hcd *hcd,
unsigned int ep_index;
unsigned long flags;
+ /*
+ * udev might be NULL if tt buffer is cleared during a failed device
+ * enumeration due to a halted control endpoint. Usb core might
+ * have allocated a new udev for the next enumeration attempt.
+ */
+
xhci = hcd_to_xhci(hcd);
udev = (struct usb_device *)ep->hcpriv;
+ if (!udev)
+ return;
slot_id = udev->slot_id;
ep_index = xhci_get_endpoint_index(&ep->desc);