CVE-2023-54027

Summary

In the Linux kernel, the following vulnerability has been resolved:

iio: core: Prevent invalid memory access when there is no parent

Commit 813665564b3d ("iio: core: Convert to use firmware node handle instead of OF node") switched the kind of nodes to use for label retrieval in device registration. Probably an unwanted change in that commit was that if the device has no parent then NULL pointer is accessed. This is what happens in the stock IIO dummy driver when a new entry is created in configfs:

mkdir /sys/kernel/config/iio/devices/dummy/foo

BUG: kernel NULL pointer dereference, address: … … Call Trace: __iio_device_register iio_dummy_probe

Since there seems to be no reason to make a parent device of an IIO dummy device mandatory, let’s prevent the invalid memory access in __iio_device_register when the parent device is NULL. With this change, the IIO dummy driver works fine with configfs.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux813665564b3d7c74412fe2877520f1d254ce948a < 312f04ede209f0a186799fe8e64a19b49700d5dcaffected
LinuxLinux813665564b3d7c74412fe2877520f1d254ce948a < a4b34cccff14ce74bb7d77fbfd56e7c9d7c28a97affected
LinuxLinux813665564b3d7c74412fe2877520f1d254ce948a < b2a69969908fcaf68596dfc04369af0fe2e1d2f7affected
LinuxLinux5.19affected
LinuxLinux0 < 5.19unaffected
LinuxLinux6.1.46 <= 6.1.*unaffected
LinuxLinux6.4.11 <= 6.4.*unaffected
LinuxLinux6.5 <= *unaffected

Weaknesses

References