linux-stable/drivers/mmc/host/cavium-thunderx.c
Jan Glauber b917c6d18c mmc: cavium: Fix use-after-free in of_platform_device_destroy
KASAN reported the following:

[   19.338655] ==================================================================
[   19.345946] BUG: KASAN: use-after-free in of_platform_device_destroy+0x88/0x100
[   19.345966] Read of size 8 at addr fffffe01aa6f1468 by task systemd-udevd/264

[   19.345983] CPU: 1 PID: 264 Comm: systemd-udevd Not tainted 4.13.0-jang+ #737
[   19.345989] Hardware name: Cavium ThunderX CN81XX board (DT)
[   19.345995] Call trace:
[   19.346013] [<fffffc800808b1b0>] dump_backtrace+0x0/0x368
[   19.346026] [<fffffc800808b6bc>] show_stack+0x24/0x30
[   19.346040] [<fffffc8008cbb944>] dump_stack+0xa4/0xc8
[   19.346057] [<fffffc80082c2870>] print_address_description+0x68/0x258
[   19.346070] [<fffffc80082c2d70>] kasan_report+0x238/0x2f8
[   19.346082] [<fffffc80082c14a8>] __asan_load8+0x88/0xb8
[   19.346098] [<fffffc8008aacee0>] of_platform_device_destroy+0x88/0x100
[   19.346131] [<fffffc8000e02fa4>] thunder_mmc_probe+0x314/0x550 [thunderx_mmc]
[   19.346147] [<fffffc800879d560>] pci_device_probe+0x158/0x1f8
[   19.346162] [<fffffc800886e53c>] driver_probe_device+0x394/0x5f8
[   19.346174] [<fffffc800886e8f4>] __driver_attach+0x154/0x158
[   19.346185] [<fffffc800886b12c>] bus_for_each_dev+0xdc/0x140
[   19.346196] [<fffffc800886d9f8>] driver_attach+0x38/0x48
[   19.346207] [<fffffc800886d148>] bus_add_driver+0x290/0x3c8
[   19.346219] [<fffffc800886fc5c>] driver_register+0xbc/0x1a0
[   19.346232] [<fffffc800879b78c>] __pci_register_driver+0xc4/0xd8
[   19.346260] [<fffffc8000e80024>] thunder_mmc_driver_init+0x24/0x10000 [thunderx_mmc]
[   19.346273] [<fffffc8008083a80>] do_one_initcall+0x98/0x1c0
[   19.346289] [<fffffc8008177b54>] do_init_module+0xe0/0x2cc
[   19.346303] [<fffffc8008175cf0>] load_module+0x3238/0x35c0
[   19.346318] [<fffffc8008176438>] SyS_finit_module+0x190/0x1a0
[   19.346329] [<fffffc80080834a0>] __sys_trace_return+0x0/0x4

This is caused by:

  platform_device_register()
   -> platform_device_unregister(to_platform_device(dev))
	freeing struct device
   -> of_node_clear_flag(dev->of_node, ...)
	writing to the freed device

The issue is solved by increasing the reference count before calling
of_platform_device_destroy() so freeing the device is postponed after
the call.

Fixes: 8fb83b1428 ("mmc: cavium: Fix probing race with regulator")
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-09-08 15:38:22 +02:00

197 lines
4.8 KiB
C

/*
* Driver for MMC and SSD cards for Cavium ThunderX SOCs.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2016 Cavium Inc.
*/
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/mmc/mmc.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/pci.h>
#include "cavium.h"
static void thunder_mmc_acquire_bus(struct cvm_mmc_host *host)
{
down(&host->mmc_serializer);
}
static void thunder_mmc_release_bus(struct cvm_mmc_host *host)
{
up(&host->mmc_serializer);
}
static void thunder_mmc_int_enable(struct cvm_mmc_host *host, u64 val)
{
writeq(val, host->base + MIO_EMM_INT(host));
writeq(val, host->base + MIO_EMM_INT_EN_SET(host));
}
static int thunder_mmc_register_interrupts(struct cvm_mmc_host *host,
struct pci_dev *pdev)
{
int nvec, ret, i;
nvec = pci_alloc_irq_vectors(pdev, 1, 9, PCI_IRQ_MSIX);
if (nvec < 0)
return nvec;
/* register interrupts */
for (i = 0; i < nvec; i++) {
ret = devm_request_irq(&pdev->dev, pci_irq_vector(pdev, i),
cvm_mmc_interrupt,
0, cvm_mmc_irq_names[i], host);
if (ret)
return ret;
}
return 0;
}
static int thunder_mmc_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
struct device_node *node = pdev->dev.of_node;
struct device *dev = &pdev->dev;
struct device_node *child_node;
struct cvm_mmc_host *host;
int ret, i = 0;
host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
if (!host)
return -ENOMEM;
pci_set_drvdata(pdev, host);
ret = pcim_enable_device(pdev);
if (ret)
return ret;
ret = pci_request_regions(pdev, KBUILD_MODNAME);
if (ret)
return ret;
host->base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0));
if (!host->base)
return -EINVAL;
/* On ThunderX these are identical */
host->dma_base = host->base;
host->reg_off = 0x2000;
host->reg_off_dma = 0x160;
host->clk = devm_clk_get(dev, NULL);
if (IS_ERR(host->clk))
return PTR_ERR(host->clk);
ret = clk_prepare_enable(host->clk);
if (ret)
return ret;
host->sys_freq = clk_get_rate(host->clk);
spin_lock_init(&host->irq_handler_lock);
sema_init(&host->mmc_serializer, 1);
host->dev = dev;
host->acquire_bus = thunder_mmc_acquire_bus;
host->release_bus = thunder_mmc_release_bus;
host->int_enable = thunder_mmc_int_enable;
host->use_sg = true;
host->big_dma_addr = true;
host->need_irq_handler_lock = true;
host->last_slot = -1;
ret = dma_set_mask(dev, DMA_BIT_MASK(48));
if (ret)
goto error;
/*
* Clear out any pending interrupts that may be left over from
* bootloader. Writing 1 to the bits clears them.
*/
writeq(127, host->base + MIO_EMM_INT_EN(host));
writeq(3, host->base + MIO_EMM_DMA_INT_ENA_W1C(host));
/* Clear DMA FIFO */
writeq(BIT_ULL(16), host->base + MIO_EMM_DMA_FIFO_CFG(host));
ret = thunder_mmc_register_interrupts(host, pdev);
if (ret)
goto error;
for_each_child_of_node(node, child_node) {
/*
* mmc_of_parse and devm* require one device per slot.
* Create a dummy device per slot and set the node pointer to
* the slot. The easiest way to get this is using
* of_platform_device_create.
*/
if (of_device_is_compatible(child_node, "mmc-slot")) {
host->slot_pdev[i] = of_platform_device_create(child_node, NULL,
&pdev->dev);
if (!host->slot_pdev[i])
continue;
ret = cvm_mmc_of_slot_probe(&host->slot_pdev[i]->dev, host);
if (ret)
goto error;
}
i++;
}
dev_info(dev, "probed\n");
return 0;
error:
for (i = 0; i < CAVIUM_MAX_MMC; i++) {
if (host->slot[i])
cvm_mmc_of_slot_remove(host->slot[i]);
if (host->slot_pdev[i]) {
get_device(&host->slot_pdev[i]->dev);
of_platform_device_destroy(&host->slot_pdev[i]->dev, NULL);
put_device(&host->slot_pdev[i]->dev);
}
}
clk_disable_unprepare(host->clk);
return ret;
}
static void thunder_mmc_remove(struct pci_dev *pdev)
{
struct cvm_mmc_host *host = pci_get_drvdata(pdev);
u64 dma_cfg;
int i;
for (i = 0; i < CAVIUM_MAX_MMC; i++)
if (host->slot[i])
cvm_mmc_of_slot_remove(host->slot[i]);
dma_cfg = readq(host->dma_base + MIO_EMM_DMA_CFG(host));
dma_cfg &= ~MIO_EMM_DMA_CFG_EN;
writeq(dma_cfg, host->dma_base + MIO_EMM_DMA_CFG(host));
clk_disable_unprepare(host->clk);
}
static const struct pci_device_id thunder_mmc_id_table[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa010) },
{ 0, } /* end of table */
};
static struct pci_driver thunder_mmc_driver = {
.name = KBUILD_MODNAME,
.id_table = thunder_mmc_id_table,
.probe = thunder_mmc_probe,
.remove = thunder_mmc_remove,
};
module_pci_driver(thunder_mmc_driver);
MODULE_AUTHOR("Cavium Inc.");
MODULE_DESCRIPTION("Cavium ThunderX eMMC Driver");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, thunder_mmc_id_table);