Null pointer dereference

In Android before security patch level 2018-04-05 on Qualcomm Snapdragon Mobile and Snapdragon Wear MDM9206, MDM9607, MDM9635M, MDM9640, MDM9645, MDM9650, MDM9655, MSM8909W, SD 210/SD 212/SD 205, SD 425, SD 430, SD 450, SD 625, SD 650/52, SD 820, SD 835, SD 845, SD 850, added a change to check if the pointer has been reset to NULL or not, before writing to the memory pointed by the pointer.