Data corruption with msdosfs (rev. 1.172 of msdosfs_vnops.c)

[Alexander Leidinger]

Quoting Philipp Mergenthaler  
<philipp.mergenthaler at stud.uni-karlsruhe.de> (from Sat, 4 Aug 2007  
16:28:54 +0200):

>
>  Hi,
>
> with rev. 1.172 of msdosfs_vnops.c I see data corruption when reading files
> on a FAT 32 file system. (I didn't try write accesses apart from deleting
> some files, which worked ok).  The file system is on a IDE disk in an
> external USB enclosure and has been created with "newfs_msdos -F 32", IIRC.
> I can use it without problems under FreeBSD-current (prior to July 20th),
> Windows XP and Linux.

I asked bde (the last one who touched the msdosfs) if he has seen your  
report. As he doesn't read -current, he hasn't. Here's his response  
(please keep him in CC):
---snip---
I haven't seen that problem here.  There is the easy workaround of mounting
with -noclusterr (except I think -noclusterr is not honored by mmap, oops).
Ask the OP if this works even with mmap (mmap can be tested using cp), and
what all the fs parameters are (newfs_msdos prints them.  Was -F 32 the onlt
parameter used?  That parameter has no effect since it is the default for
non-small filesystems).
---snip---

Bye,
Alexander.

-- 
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