Re: Flaw in ext2?

Pavel Machek (pavel@bug.ucw.cz)
Thu, 1 Apr 1999 21:42:33 +0200


Hi!

> > The version of the kernel that you have deletes the inode number from the directory when
> > it deletes the file. This makes us lose the connection between the name and the data.
> > So we have names and we have inodes which point to data but the connection between the 2
> > is lost. This version also deletes the indirect block. These are the blocks that point to > 63kb sections of the file. Once a file gets over 12 blocks long (about 6k) the system the
> > system stores the address pointers on the disk. In indirect blocks. Each indirect block
> > points to 64kb of data. Anyway these are also zeroed out. I know of no other unix that
> > zeros the indirect blocks. Most of the unix recoveries I have done is where the system is > corrupted and wont mount. I have also done unixes that have been deleted and used the
> > indirect blocks to recover vast amounts of data. I didn't realize that linux zeroed the
> > indirect blocks.
>
> The worrisome part, of course, is the "I know of no other Unix that does
> this."
>
> Could someone who is in the know please provide me with a source,
> perhaps, for the answer to this question?

Something similar happened to our artax server.

2.0.0 clears indirect blocks. That is fixed in 2.2.X.
Pavel

-- 
I'm really pavel@atrey.karlin.mff.cuni.cz. 	   Pavel
Look at http://atrey.karlin.mff.cuni.cz/~pavel/ ;-).

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