kernel: drm/amd/display: Add NULL test for 'timing generator' in 'dcn21_set_pipe()'

A NULL pointer dereference flaw was found in the Linux kernel in dcn21setpipe. This issue may lead to a crash...

Linux kernel 安全漏洞

Linux kernel is the kernel used by Linux, the open source operating system of the Linux Foundation in the United States. A security vulnerability exists in the Linux kernel that stems from a missing NULL test in the timing generator in dcn21setpipe...