misc/123939: msdosfs corruptes new files

[Martin Laabs]

>Number:         123939
>Category:       misc
>Synopsis:       msdosfs corruptes new files
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri May 23 19:20:03 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator:     Martin Laabs
>Release:        7.0-RELEASE-p1
>Organization:
>Environment:
FreeBSD martin.laabs 7.0-RELEASE FreeBSD 7.0-RELEASE #0: Sun Feb 24 19:59:52 UTC 2008     root at logan.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  i386

Muvo V100 MP3 Player
>Description:
If I mount my USB mass storage device (a MP3-Player in my case) and create some files they get corrupted. I can nearly exclude a defect since the device worked with fine the 6.3 RELEASE and also works if I copy files with Windows.
There is also an other strange behaviour. Some time I mount the device to i.e. /mnt but if I ls the directory it is empty (but mount says the device is mounted.) If I demount the device and mount it i.e. to /dos I can access the files. Although some directories are marked as files and can therfore be not accessed.
I checked the device with the microsoft scandisc and it reported no errors. However fsck_msdosfs claims an "Invalid signature in boot block: 0000".

Reading of the device does work, expect of the directory problem, properly.
>How-To-Repeat:
# dd if=/dev/zero of=/dev/da7s1 bs=128k
dd: /dev/da7s1: short write on character device
dd: /dev/da7s1: end of device
7410+0 records in
7409+1 records out
971120640 bytes transferred in 1399.775541 secs (693769 bytes/sec)

# newfs_msdos /dev/da7s1 
/dev/da7s1: 473246 sectors in 236623 FAT32 clusters (4096 bytes/cluster)
bps=2048 spc=2 res=8 nft=2 mid=0xf0 spt=32 hds=64 hid=0 bsec=474180 bspf=463 
rdcl=2 infs=1 bkbs=2

# mount -tmsdosfs /dev/da7s1 /mnt
# cp /media/Music/Tony/Duncan\ Sheik\ -\ White\ Limousine/01\ -\ Hey\ Casanova.mp3 /mnt
# diff /media/Music/Tony/Duncan\ Sheik\ -\ White\ Limousine/01\ -\ Hey\ Casanova.mp3 /mnt

# umount /mnt
# mount -tmsdosfs /dev/da7s1 /mnt

# diff /media/Music/Tony/Duncan\ Sheik\ -\ White\ Limousine/01\ -\ Hey\ Casanova.mp3 /mnt
Files /media/Music/Tony/Duncan Sheik - White Limousine/01 - Hey Casanova.mp3 and /mnt/01 - Hey Casanova.mp3 differ


>Fix:


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