In the Linux kernel, the following vulnerability has been resolved:
ACPI: processor_idle: Fix memory leak in acpi_processor_power_exit()
After unregistering the CPU idle device, the memory associated with it is not freed, leading to a memory leak:
unreferenced object 0xffff896282f6c000 (size 1024): comm swapper/0, pid 1, jiffies 4294893170 hex dump (first 32 bytes): 00 00 00 00 0b 00 00 00 00 00 00 00 00 00 00 00 ……………. 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ……………. backtrace (crc 8836a742): [] kmalloc_trace+0x29d/0x340 [] acpi_processor_power_init+0xf3/0x1c0 [] __acpi_processor_start+0xd3/0xf0 [] acpi_processor_start+0x2c/0x50 [] really_probe+0xe2/0x480 [] __driver_probe_device+0x78/0x160 [] driver_probe_device+0x1f/0x90 [] __driver_attach+0xce/0x1c0 [] bus_for_each_dev+0x70/0xc0 [] bus_add_driver+0x112/0x210 [] driver_register+0x55/0x100 [] acpi_processor_driver_init+0x3b/0xc0 [] do_one_initcall+0x41/0x300 [] kernel_init_freeable+0x320/0x470 [] kernel_init+0x16/0x1b0 [] ret_from_fork+0x2d/0x50
Fix this by freeing the CPU idle device after unregistering it.