CVE-2022-50616— regulator: core: Use different devices for resource allocation and DT lookup

regulator: core: Use different devices for resource allocation and DT lookup

In the Linux kernel, the following vulnerability has been resolved: regulator: core: Use different devices for resource allocation and DT lookup 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.

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Linux kernel 安全漏洞

Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于regulator核心使用相同设备进行资源分配和DT查找，可能导致UAF问题。

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