An issue was discovered in the Linux kernel through 4.17.10. There is a NULL pointer dereference and panic in hfsplus_lookup() in fs/hfsplus/dir.c when opening a file (that is purportedly a hard link) in an hfs+ filesystem that has malformed catalog data, and is mounted read-only without a metadata directory. https://nvd.nist.gov/vuln/detail/CVE-2018-14617
