Hi all, This is a pile of fuzzing tests for ext4 and XFS filesystems. Included are general fuzzers that create, populate, and fuzz a scratch filesystem; and targeted fuzzers that create specific types of metadata blocks and test the filesystem's reaction to the corruption. Each fuzzing test has roughly the same structure: First, the scratch device is formatted and populated with enough files and directories so that the targeted metadata is created. Next, the metadata block is randomly mutated to some arbitrary degree. Then, the filesystem is mounted and exercised to see if the kernel will fling error codes back to userspace without crashing. After that, the repair tool is invoked to fix all the damage. Finally, the filesystem is remounted and exercised again to ensure that the errors have gone away. The first patch provides common code that can populate ext4 and XFS filesystems containing (hopefully) every possible type of metadata block, and a few other common code bits. The second patch implements general fuzzers for ext4 and XFS. A scratch FS is created and populated with all types of metadata before fuzzing begins. The third and fourth patches implement targeted fuzzing for block group, bitmap, file, extent, and directory metadata in ext4. Patches 5-7 implement targeted fuzzing for AGs, btrees, file, extent, and directory metadata in XFS. I've tested these xfstests changes against the master branch as of 8/03. The reflink tests will be dealt with separately. The xfs fuzzers require xfsprogs with the August 2015 xfsprogs patchbomb applied. The ext4 fuzzers do not require patches if your e2fsprogs are current. Scary rewound github repo with everything attached: https://github.com/djwong/xfstests and for the xfsprogs patches: https://github.com/djwong/xfsprogs Comments and questions are, as always, welcome. --D -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
