On Sat, Apr 18, 2015 at 12:20 AM, Tom Marshall <tom@xxxxxxxxx> wrote: > So, I wrote a thing called 'zfile' that hooks into the VFS layer and > intercepts file_operations to do file (de)compression on the fly. When a > file is opened, it reads and decompresses the data into memory. The file > may be read, written, and mmaped in the usual way. If the contents are > changed, the data is compressed and written back. A working patch for an > older kernel version may be found at: > http://review.cyanogenmod.org/#/c/95220/ So, I've extracted the patch from that website and gave a quick review. I'm pretty sure VFS folks will hate the VFS layering you do. Beside of that you decompress the *whole* file into memory at open() time. This will explode as soon you deal with bigger files. Also you seem to trust the user.compression.realsize xattr provided by userspace. That looks exploitable. Back to my original question, why not FUSE? Or add compression support to ecryptfs... -- Thanks, //richard -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
