From e873c74132f0c5f1452816cd9bb26208f0bba1e1 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Sat, 22 Aug 2026 19:22:05 +0000 Subject: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() When dma_device_put() drops the last reference on chan->device->ref, dma_device_release() runs and may free the dma_device along with its channels. dma_chan_put() then still reads chan->device->owner via dma_chan_to_owner() for the trailing module_put(). KASAN catches it: slab-use-after-free in dma_chan_put+0x3e6/0x4c0 Read of size 8 by task insmod/6319 Freed by task 6319: kfree+0x225/0x470 dma_chan_put+0x395/0x4c0 dmaengine_put+0xf8/0x160 Cache the module owner in dma_chan_put() before the put so the trailing module_put() does not need chan->device. Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct") Suggested-by: Sashiko Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com Reviewed-by: Frank Li Reviewed-by: Logan Gunthorpe Signed-off-by: Shivank Garg Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com Signed-off-by: Vinod Koul --- drivers/input/touchscreen/tsc2004.c | 73 +++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) create mode 100644 drivers/input/touchscreen/tsc2004.c (limited to 'drivers/input/touchscreen/tsc2004.c') diff --git a/drivers/input/touchscreen/tsc2004.c b/drivers/input/touchscreen/tsc2004.c new file mode 100644 index 000000000..130aeb735 --- /dev/null +++ b/drivers/input/touchscreen/tsc2004.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * TSC2004 touchscreen driver + * + * Copyright (C) 2015 QWERTY Embedded Design + * Copyright (C) 2015 EMAC Inc. + */ + +#include +#include +#include +#include +#include +#include "tsc200x-core.h" + +static const struct input_id tsc2004_input_id = { + .bustype = BUS_I2C, + .product = 2004, +}; + +static int tsc2004_cmd(struct device *dev, u8 cmd) +{ + u8 tx = TSC200X_CMD | TSC200X_CMD_12BIT | cmd; + s32 data; + struct i2c_client *i2c = to_i2c_client(dev); + + data = i2c_smbus_write_byte(i2c, tx); + if (data < 0) { + dev_err(dev, "%s: failed, command: %x i2c error: %d\n", + __func__, cmd, data); + return data; + } + + return 0; +} + +static int tsc2004_probe(struct i2c_client *i2c) + +{ + return tsc200x_probe(&i2c->dev, i2c->irq, &tsc2004_input_id, + devm_regmap_init_i2c(i2c, &tsc200x_regmap_config), + tsc2004_cmd); +} + +static const struct i2c_device_id tsc2004_idtable[] = { + { .name = "tsc2004" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, tsc2004_idtable); + +#ifdef CONFIG_OF +static const struct of_device_id tsc2004_of_match[] = { + { .compatible = "ti,tsc2004" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, tsc2004_of_match); +#endif + +static struct i2c_driver tsc2004_driver = { + .driver = { + .name = "tsc2004", + .dev_groups = tsc200x_groups, + .of_match_table = of_match_ptr(tsc2004_of_match), + .pm = pm_sleep_ptr(&tsc200x_pm_ops), + }, + .id_table = tsc2004_idtable, + .probe = tsc2004_probe, +}; +module_i2c_driver(tsc2004_driver); + +MODULE_AUTHOR("Michael Welling "); +MODULE_DESCRIPTION("TSC2004 Touchscreen Driver"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1