misc/104133: EXT2FS module corrupts EXT2/3 filesystems

[Bjoern Voigt]

>Number:         104133
>Category:       misc
>Synopsis:       EXT2FS module corrupts EXT2/3 filesystems
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sat Oct 07 20:10:19 GMT 2006
>Closed-Date:
>Last-Modified:
>Originator:     Bjoern Voigt
>Release:        6.2-PRERELEASE
>Organization:
>Environment:
FreeBSD mybox 6.2-PRERELEASE FreeBSD 6.2-PRERELEASE #0: Tue Sep 12 18:28:25 CEST 2006
>Description:
FreeBSDs EXT2FS module seems to corrupt EXT2 and EXT3 filesystems in R/W mount mode. 

The tested filesystem is configured as an EXT3 filesystem (EXT2 + journal). Normally EXT3 filesystems can be used as EXT2 filesystems without problems.

After unmounting the filesystem e2fsck says that the filesystem is "clean". But Linux find's filesystem errors in such filesystems. Also e2fsck under Linux and FreeBSD finds errors in a forced check.

# umount -a -text2fs
# fsck -p -f -t ext2fs /dev/ad1s7
/dev/ad1s7: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.
        (i.e., without -a or -p options)
# fsck -f -t ext2fs /dev/ad1s7
e2fsck 1.39 (29-May-2006)
Pass 1: Checking inodes, blocks, and sizes
Inode 2025329 has a bad extended attribute block 4129938.  Clear<y>? yes
Inode 2025322 has a bad extended attribute block 4132380.  Clear<y>? yes
Inode 2025338 has a bad extended attribute block 4132399.  Clear<y>? yes
Inode 2025327 has a bad extended attribute block 4172620.  Clear<y>? yes
Inode 2025348, i_blocks is 0, should be 8.  Fix<y>? yes
[...]
>How-To-Repeat:
1. Mount an EXT2/3 filesystem under FreeBSD in R/W mode
   e.g. mount -a -t ext2fs
2. Use it (heavy usage like compiling a source code increases the amount of filesystem errors)
3. Unmount the EXT2/3 filesystem under FreeBSD
   e.g. umount -a -t ext2fs
4. Force an fsck check
   e.g. fsck -f -t ext2fs /dev/XXX
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted: