The Linux kernel before 5.1-rc5 allows page->_refcount reference count
overflow, with resultant use-after-free issues, if about 140 GiB of RAM
exists. This is related to fs/fuse/dev.c, fs/pipe.c, fs/splice.c,
include/linux/mm.h, include/linux/pipe_fs_i.h, kernel/trace/trace.c,
mm/gup.c, and mm/hugetlb.c. It can occur with FUSE requests.

It was discovered that an integer overflow existed in the Linux kernel when
reference counting pages, leading to potential use-after-free issues. A
local attacker could use this to cause a denial of service (system crash)
or possibly execute arbitrary code.

tyhicks

Requires >= 140 GiB of RAM which is rare