Linux Kernel BCM2835 SPI NULL Pointer Dereference Vulnerability

A vulnerability in the Linux kernel's BCM2835 SPI driver can lead to a NULL pointer dereference. This issue occurs in versions of the kernel that include the problematic commit, when an IRQ-based transfer times out. The 'bcm2835_spi_handle_err()' function is then called, but if the controller's DMA transmit or receive pointers are not set, it results in a NULL pointer dereference. The vulnerability has been addressed by adding checks to ensure these pointers are valid before they are accessed.

Impact

Exploitation of this vulnerability can cause a NULL pointer dereference, leading to a crash of the kernel or the affected process.