linux/drivers/usb/host/xhci-mvebu.c
Kees Cook 0fbd2cda92 usb: host: xhci: mvebu: Iterate over array indexes instead of using pointer math
Walking the dram->cs array was seen as accesses beyond the first array
item by the compiler. Instead, use the array index directly. This allows
for run-time bounds checking under CONFIG_UBSAN_BOUNDS as well. Seen
with GCC 13 with -fstrict-flex-arrays:

In function 'xhci_mvebu_mbus_config',
    inlined from 'xhci_mvebu_mbus_init_quirk' at ../drivers/usb/host/xhci-mvebu.c:66:2:
../drivers/usb/host/xhci-mvebu.c:37:28: warning: array subscript 0 is outside array bounds of 'const struct mbus_dram_window[0]' [-Warray-bounds=]
   37 |                 writel(((cs->size - 1) & 0xffff0000) | (cs->mbus_attr << 8) |
      |                          ~~^~~~~~

Cc: Mathias Nyman <mathias.nyman@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230204183651.never.663-kees@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-06 13:46:42 +01:00

86 lines
2.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2014 Marvell
* Author: Gregory CLEMENT <gregory.clement@free-electrons.com>
*/
#include <linux/io.h>
#include <linux/mbus.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include "xhci-mvebu.h"
#include "xhci.h"
#define USB3_MAX_WINDOWS 4
#define USB3_WIN_CTRL(w) (0x0 + ((w) * 8))
#define USB3_WIN_BASE(w) (0x4 + ((w) * 8))
static void xhci_mvebu_mbus_config(void __iomem *base,
const struct mbus_dram_target_info *dram)
{
int win;
/* Clear all existing windows */
for (win = 0; win < USB3_MAX_WINDOWS; win++) {
writel(0, base + USB3_WIN_CTRL(win));
writel(0, base + USB3_WIN_BASE(win));
}
/* Program each DRAM CS in a seperate window */
for (win = 0; win < dram->num_cs; win++) {
const struct mbus_dram_window *cs = &dram->cs[win];
writel(((cs->size - 1) & 0xffff0000) | (cs->mbus_attr << 8) |
(dram->mbus_dram_target_id << 4) | 1,
base + USB3_WIN_CTRL(win));
writel((cs->base & 0xffff0000), base + USB3_WIN_BASE(win));
}
}
int xhci_mvebu_mbus_init_quirk(struct usb_hcd *hcd)
{
struct device *dev = hcd->self.controller;
struct platform_device *pdev = to_platform_device(dev);
struct resource *res;
void __iomem *base;
const struct mbus_dram_target_info *dram;
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (!res)
return -ENODEV;
/*
* We don't use devm_ioremap() because this mapping should
* only exists for the duration of this probe function.
*/
base = ioremap(res->start, resource_size(res));
if (!base)
return -ENODEV;
dram = mv_mbus_dram_info();
xhci_mvebu_mbus_config(base, dram);
/*
* This memory area was only needed to configure the MBus
* windows, and is therefore no longer useful.
*/
iounmap(base);
return 0;
}
int xhci_mvebu_a3700_init_quirk(struct usb_hcd *hcd)
{
struct xhci_hcd *xhci = hcd_to_xhci(hcd);
/* Without reset on resume, the HC won't work at all */
xhci->quirks |= XHCI_RESET_ON_RESUME;
return 0;
}