Messages in this thread |  | | Date | Fri, 21 Sep 2001 00:00:35 -0400 (EDT) | From | Alexander Viro <> | Subject | Re: Linux 2.4.10-pre11 |
| |
On Fri, 21 Sep 2001, Andrea Arcangeli wrote:
> Famous last words, after a few hours of debugging mixed with vm patches > and emails, I finally got around finding the real bug. The fact is that > the secure-ramdisk logic was totally broken, not just for initrd, oh > well, so please don't apply such patch (code in mainline has the > security issue if you allow an luser to read from /dev/ram0, but it > isn't buggy). and the issue is quite unfixable with just a PageSecure > set inside rd.c. The fact is that I cannot just clear-around the > written "bh", around there could be the source for the next block to > write and I cannot zero it out. It is getting harder to fix this one > just inside the ->make_request callback... Hints?
Well, taking a file on ramfs and doing losetup on it should be equivalent to ramdisk. Turning relevant pieces into a driver shouldn't be too hard. It won't be pretty, though - you'll probably want different address_space_operations, so that read()/write() wouldn't bother with requests at all.
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|  |