lkml.org 
[lkml]   [2019]   [Aug]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] usb: xhci-pci: reorder removal to avoid use-after-free
Date
On driver removal, the platform_device_unregister call
attached through devm_add_action_or_reset was executed
after usb_hcd_pci_remove.
This lead to a use-after-free for the iomem resorce of
the xhci-ext-caps driver in the platform removal
because the parent of the resource was freed earlier.

Fix this by reordering of the removal sequence.

Signed-off-by: Carsten Schmid <carsten_schmid@mentor.com>
---
drivers/usb/host/xhci-ext-caps.c | 22 ++++++++++++----------
drivers/usb/host/xhci-pci.c | 4 ++++
drivers/usb/host/xhci-pci.h | 19 +++++++++++++++++++
drivers/usb/host/xhci.h | 1 +
4 files changed, 36 insertions(+), 10 deletions(-)
create mode 100644 drivers/usb/host/xhci-pci.h

diff --git a/drivers/usb/host/xhci-ext-caps.c b/drivers/usb/host/xhci-ext-caps.c
index 399113f9fc5c..d2ab1e2a39c0 100644
--- a/drivers/usb/host/xhci-ext-caps.c
+++ b/drivers/usb/host/xhci-ext-caps.c
@@ -7,21 +7,19 @@

#include <linux/platform_device.h>
#include "xhci.h"
+#include "xhci-pci.h"

#define USB_SW_DRV_NAME "intel_xhci_usb_sw"
#define USB_SW_RESOURCE_SIZE 0x400

-static void xhci_intel_unregister_pdev(void *arg)
-{
- platform_device_unregister(arg);
-}
-
static int xhci_create_intel_xhci_sw_pdev(struct xhci_hcd *xhci, u32 cap_offset)
{
struct usb_hcd *hcd = xhci_to_hcd(xhci);
struct device *dev = hcd->self.controller;
struct platform_device *pdev;
struct resource res = { 0, };
+ struct xhci_pci_priv *priv = (struct xhci_pci_priv *)xhci->priv;
+
int ret;

pdev = platform_device_alloc(USB_SW_DRV_NAME, PLATFORM_DEVID_NONE);
@@ -52,11 +50,7 @@ static int xhci_create_intel_xhci_sw_pdev(struct xhci_hcd *xhci, u32 cap_offset)
return ret;
}

- ret = devm_add_action_or_reset(dev, xhci_intel_unregister_pdev, pdev);
- if (ret) {
- dev_err(dev, "couldn't add unregister action for intel_xhci_usb_sw pdev\n");
- return ret;
- }
+ priv->pdev = pdev;

return 0;
}
@@ -88,3 +82,11 @@ int xhci_ext_cap_init(struct xhci_hcd *xhci)
return 0;
}
EXPORT_SYMBOL_GPL(xhci_ext_cap_init);
+
+void xhci_ext_cap_remove(struct xhci_hcd *xhci)
+{
+ struct xhci_pci_priv *priv = (struct xhci_pci_priv *)xhci->priv;
+ if (priv->pdev)
+ platform_device_unregister(priv->pdev);
+}
+EXPORT_SYMBOL_GPL(xhci_ext_cap_remove);
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index c2fe218e051f..a4d094df56f7 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -14,6 +14,7 @@
#include <linux/acpi.h>

#include "xhci.h"
+#include "xhci-pci.h"
#include "xhci-trace.h"

#define SSIC_PORT_NUM 2
@@ -62,6 +63,7 @@ static struct hc_driver __read_mostly xhci_pci_hc_driver;
static int xhci_pci_setup(struct usb_hcd *hcd);

static const struct xhci_driver_overrides xhci_pci_overrides __initconst = {
+ .extra_priv_size = sizeof(struct xhci_pci_priv),
.reset = xhci_pci_setup,
};

@@ -393,6 +395,8 @@ static void xhci_pci_remove(struct pci_dev *dev)
xhci->shared_hcd = NULL;
}

+ xhci_ext_cap_remove(xhci);
+
/* Workaround for spurious wakeups at shutdown with HSW */
if (xhci->quirks & XHCI_SPURIOUS_WAKEUP)
pci_set_power_state(dev, PCI_D3hot);
diff --git a/drivers/usb/host/xhci-pci.h b/drivers/usb/host/xhci-pci.h
new file mode 100644
index 000000000000..ead9618d7368
--- /dev/null
+++ b/drivers/usb/host/xhci-pci.h
@@ -0,0 +1,19 @@
+/*
+ * xhci-pci.h - xHCI extended capability handling platform Glue.
+ *
+ * Copyright (C) 2019 Mentor Graphics (Deutschland) GmbH
+ * Derived from xhci-plat.h
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ */
+
+#ifndef _XHCI_PCI_H
+#define _XHCI_PCI_H
+
+struct xhci_pci_priv {
+ struct platform_device *pdev;
+};
+
+#endif /* _XHCI_PCI_H */
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index fabbce1c542a..847d2021fc2c 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -2052,6 +2052,7 @@ void xhci_init_driver(struct hc_driver *drv,
const struct xhci_driver_overrides *over);
int xhci_disable_slot(struct xhci_hcd *xhci, u32 slot_id);
int xhci_ext_cap_init(struct xhci_hcd *xhci);
+void xhci_ext_cap_remove(struct xhci_hcd *xhci);

int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup);
int xhci_resume(struct xhci_hcd *xhci, bool hibernated);
--
2.17.1
\
 
 \ /
  Last update: 2019-08-14 13:40    [W:0.035 / U:77.940 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site