Following by the below discussion, there's the potential UAF issue
between regulator and mfd.
https://lore.kernel.org/all/20221128143601.1698148-1-yangyingliang@huawei.com/
From the analysis of Yingliang
CPU A |CPU B
mt6370_probe() |
devm_mfd_add_devices() |
|mt6370_regulator_probe()
| regulator_register()
| //allocate init_data and add it to devres
| regulator_of_get_init_data()
i2c_unregister_device() |
device_del() |
devres_release_all() |
// init_data is freed |
release_nodes() |
| // using init_data causes UAF
| regulator_register()
It's common to use mfd core to create child device for the regulator.
In order to do the DT lookup for init data, the child that registered
the regulator would pass its parent as the parameter. And this causes
init data resource allocated to its parent, not itself. The issue happen
when parent device is going to release and regulator core is still doing
some operation of init data constraint for the regulator of child device.
To fix it, this patch expand 'regulator_register' API to use the
different devices for init data allocation and DT lookup.
Reported-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
Link: https://lore.kernel.org/r/1670311341-32664-1-git-send-email-u0084500@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Using pm_runtime_resume_and_get is more appropriate
for simplifing code
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
Link: https://lore.kernel.org/r/20220412071030.2532230-1-chi.minghao@zte.com.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
There maybe an overshoot, when disabling, then re-enabling vrefbuf
too quickly. VREFBUF is used by ADC/DAC on some boards. When re-enabling
too quickly, an overshoot on the reference voltage make the conversions
inaccurate for a short period of time.
- Don't put the VREFBUF in HiZ when disabling, to force an active
discharge.
- Enforce a 1ms OFF/ON delay
Fixes: 0cdbf481e9 ("regulator: Add support for stm32-vrefbuf")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Message-Id: <1583312132-20932-1-git-send-email-fabrice.gasnier@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Based on 1 normalized pattern(s):
license terms gnu general public license gpl version 2
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 161 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170027.447718015@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for suspend/resume and runtime PM to stm32-vrefbuf driver.
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
stm32_vrefbuf_enable() wrongly checks VRR bit: 0 stands for not ready,
1 for ready. It currently checks the opposite.
This makes enable routine to exit immediately without waiting for ready
flag.
Fixes: 0cdbf481e9 ("regulator: Add support for stm32-vrefbuf")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Add regulator driver for STM32 voltage reference buffer which can be
used as voltage reference for ADCs, DACs and external components through
dedicated VREF+ pin.
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
