1.6 KiB
CVE-2024-44950
Description
In the Linux kernel, the following vulnerability has been resolved:serial: sc16is7xx: fix invalid FIFO access with special register setWhen enabling access to the special register set, Receiver time-out andRHR interrupts can happen. In this case, the IRQ handler will try to readfrom the FIFO thru the RHR register at address 0x00, but address 0x00 ismapped to DLL register, resulting in erroneous FIFO reading.Call graph example: sc16is7xx_startup(): entry sc16is7xx_ms_proc(): entry sc16is7xx_set_termios(): entry sc16is7xx_set_baud(): DLH/DLL = $009C --> access special register set sc16is7xx_port_irq() entry --> IIR is 0x0C sc16is7xx_handle_rx() entry sc16is7xx_fifo_read(): --> unable to access FIFO (RHR) because it is mapped to DLL (LCR=LCR_CONF_MODE_A) sc16is7xx_set_baud(): exit --> Restore access to general register setFix the problem by claiming the efr_lock mutex when accessing the Specialregister set.
POC
Reference
No PoCs from references.