Sensor drivers, in general, do not have any access to memory that they did not own before being registered. For example, if a sensor registers a buffer that was copied from user memory, the sensor driver is the only one that could have done that. This could lead to a sensor driver reading from or writing to kernel memory that it does not own. This out of bounds read or write can result in a local denial of service in the sensor driver. Sensor drivers are not subject to the same code review standards as other code. One reason for this is that sensor drivers are often developed by networking and other non-kernel developers. Another reason is that sensor drivers are often developed by non-programmers. Sensor drivers are often developed by vendors and sensor hardware companies. Vendors and sensor hardware companies often do not follow the same coding standards as other developers. Vendors and sensor hardware companies often do not follow the same security standards as other developers. This means that the same code review standards and security standards that are normally used for other code might not be used for sensor drivers.

What to do if you own Sensor Drivers

If a sensor driver is owned by you, the following actions should be taken:

- If the device does not have an I2C interface, use the kernel's I2C subsystem to access the device.
- If the device has an I2C interface and you are using an I2C client, ask your manufacturer or sensor hardware company to disable I2C access on that interface.

Mitigation Strategies for Sensor Driver Out of Bounds Reads

One mitigation strategy is to register the buffers with a higher limit. This would make it harder for a sensor driver to read or write these buffers, which could help avoid a local denial of service in the sensor driver.

Can a Sensor Driver Be Vulnerable to Out of Bounds Reads?

Sensors are designed to provide information on the outside world, but not directly into the kernel. This means that the sensor driver has no direct access to memory of its own. The design of sensors makes them inherently vulnerable to out-of-bounds reads and writes because they cannot be verified by any other code. For example, a sensor could be programmed with a buffer that allows it to read from user or kernel memory, but then the programmer could accidentally write a pointer to user memory in that buffer. Then, when the sensor is running, it will crash when it tries to read from a location it does not have access to. Another example is if a sensor driver registers memory for itself that was copied from user space and then subsequently uses those buffers for something else in the driver. If there are out-of-bounds writes in any part of the system, it's possible for an attacker who can control hardware or firmware (or both) to cause a denial of service attack on the sensor drivers themselves.

Detecting Sensors with Checksums

To detect sensors with checksums, a process can compare all of the sensor's registers and memory-mapped registers to a table of known checksums. If a register matches a known checksum, this would be an indication that the register is part of the corresponding sensor driver. If no match is found, the process can use various methods, such as stack traces or program counter values, to determine what was loaded at that address.

CVE-2023-39123

The flaw is that sensor drivers are not subject to the same code review standards as other code. One reason for this is that sensor drivers are often developed by networking and other non-kernel developers. Another reason is that sensor drivers are often developed by non-programmers. Sensor drivers are often developed by vendors and sensor hardware companies. Vendors and sensor hardware companies often do not follow the same coding standards as other developers. Vendors and sensor hardware companies often do not follow the same security standards as other developers. This means that the same code review standards and security standards that are normally used for other code might not be used for sensor drivers.
If you want your website to rank in Google, you have to take time to consider SEO, which can be challenging without the skills or time to go through a comprehensive process. Outsourcing SEO services can be a great option if you're looking for an expert who's done all the work of finding key strategic goals and then left the complex process of meeting those goals to industry experts.

Timeline

Published on: 10/14/2022 19:15:00 UTC
Last modified on: 10/18/2022 18:12:00 UTC

References