In the Linux kernel, the following vulnerability has been resolved: mtd: ubi: Release device reference on busy detach ubi_detach_mtd_dev() obtains a device reference through ubi_get_device() before checking whether the UBI device is busy. The busy return path drops ubi->ref_count but leaves the device reference held, so the device object cannot be released after a later detach. Drop the device reference before returning -EBUSY.
https://git.kernel.org/stable/c/e065960366b55ab21e6c643c30dec2a41451900b
https://git.kernel.org/stable/c/87812858c4c8df979cb70bcd0040b925a543df6f
https://git.kernel.org/stable/c/851c5e9a829d56cb0982965f07ef8966a6722884
https://git.kernel.org/stable/c/31dd710cd84d5dd63c49f640d3a9f36c9699ca95