CVE-2024-57934 fgraph: Add READ_ONCE() when accessing fgraph_array[]

In the Linux kernel, the following vulnerability has been resolved: fgraph: Add READONCE when accessing fgrapharray In ftracereturntohandler, a loop iterates over the fgrapharray elements, which are fgraphops. The loop checks if an element is a fgraphstub to prevent using a fgraphstub afterward...