EXT3 fuzzing

hi,

after fsfuzz
(http://www.securityfocus.com/archive/1/449568/30/0/threaded) was released i decided to give it a spin. So far I got two problematic images:

http://www.cobra-basket.de/ext3_ls_prozzy_hog.img.bz2
which makes the kernel use as much cpu as it can get

http://www.cobra-basket.de/ext3_memhog.img.bz2
eats all memory it can get

I enabled jbd debugging for a while, and the traces looked similar, but made not much sense to me. kmemleak locked my box, so I was not able to get some debugging info from there.
To test the images, just mount them, and do an ls on the image.

Greetings, Eric

 www.cobra-basket.de -- just my stuff

Hi Eric, I recently posted a patch to LKML ([PATCH] handle ext3 directory corruption better) to handle the broken fuzz cases I found. You might try again w/ that patch... I can also give your images a whirl. With the patch I submitted, I had thousands of successful fsfuzz runs. The only snag I hit was actually an fsfuzz bug; lost+found/ had been fuzzed so it looked like a pipe, and the "cat" part of the test hung up - not really an ext3 bug.

Thanks,

-Eric

Works for me w/ that patch:

[root@link-07 ~]# mount -o loop ext3_ls_prozzy_hog.img mnt/ [root@link-07 ~]# ls mnt/
[root@link-07 ~]# dmesg | tail -n 6
EXT3-fs: mounted filesystem with ordered data mode. EXT3-fs error (device loop0): htree_dirblock_to_tree: bad entry in directory #2: rec_len % 4 != 0 - offset=24, inode=11, rec_len=989, name_len=10
Aborting journal on device loop0.
ext3_abort called.
EXT3-fs error (device loop0): ext3_journal_start_sb: Detected aborted journal
Remounting filesystem read-only

[root@link-07 ~]# mount -o loop ext3_memhog.img mnt/ [root@link-07 ~]# ls mnt
[root@link-07 ~]# dmesg | tail -n 6
EXT3-fs: mounted filesystem with ordered data mode. EXT3-fs error (device loop0): htree_dirblock_to_tree: bad entry in directory #2: rec_len is smaller than minimal - offset=0, inode=75, rec_len=0, name_len=0
Aborting journal on device loop0.
ext3_abort called.
EXT3-fs error (device loop0): ext3_journal_start_sb: Detected aborted journal
Remounting filesystem read-only

-Eric