CVE-2022-49049 mm/secretmem: fix panic when growing a memfd_secret

In the Linux kernel, the following vulnerability has been resolved: mm/secretmem: fix panic when growing a memfdsecret When one tries to grow an existing memfdsecret with ftruncate, one gets a panic 1. For example, doing the following reliably induces the panic: fd = memfdsecret; ftruncatefd, 10;...