EXT4 Gets Extra Protection Against Maliciously Crafted Container Images
Ted Ts'o today sent in the EXT4 Linux file-system updates and it's mostly mundane maintenance work with no major features this cycle. He did note of the bug fixes to protect against potentially malicious EXT4 file-system images.
Ted commented, "Cleanups and bugfixes for ext4, including some fixes to make ext4 more robust against maliciously crafted file system images. (I still don't recommend that container folks hold any delusions that mounting arbitary images that can be crafted by malicious attackers should be considered sane thing to do, though!)"
The roughly two dozen changes for EXT4 in Linux 4.17 can be found here.