From: Al Viro <viro@zeniv.linux.org.uk>
To: "Pali Rohár" <pali.rohar@gmail.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
"Theodore Y. Ts'o" <tytso@mit.edu>,
Namjae Jeon <linkinjeon@gmail.com>,
Gabriel Krisman Bertazi <krisman@collabora.com>
Subject: Re: vfat: Broken case-insensitive support for UTF-8
Date: Tue, 21 Jan 2020 00:07:01 +0000 [thread overview]
Message-ID: <20200121000701.GG8904@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20200120235745.hzza3fkehlmw5s45@pali>
On Tue, Jan 21, 2020 at 12:57:45AM +0100, Pali Rohár wrote:
> On Monday 20 January 2020 22:46:25 Al Viro wrote:
> > On Mon, Jan 20, 2020 at 10:40:46PM +0100, Pali Rohár wrote:
> >
> > > Ok, I did some research. It took me it longer as I thought as lot of
> > > stuff is undocumented and hard to find all relevant information.
> > >
> > > So... fastfat.sys is using ntos function RtlUpcaseUnicodeString() which
> > > takes UTF-16 string and returns upper case UTF-16 string. There is no
> > > mapping table in fastfat.sys driver itself.
> >
> > Er... Surely it's OK to just tabulate that function on 65536 values
> > and see how could that be packed into something more compact?
>
> It is OK, but too complicated. That function is in nt kernel. So you
> need to build a new kernel module and also decide where to put output of
> that function. It is a long time since I did some nt kernel hacking and
> nowadays you need to download 10GB+ of Visual Studio code, then addons
> for building kernel modules, figure out how to write and compile simple
> kernel module via Visual Studio, write ini install file, try to load it
> and then you even fail as recent Windows kernels refuse to load kernel
> modules which are not signed...
Wait a sec... From NT userland, on a mounted VFAT:
for all s in single-codepoint strings
open s for append
if failed
print s on stderr, along with error value
write s to the opened file, adding to its tail
close the file
the for each equivalence class you'll get a single file, with all
members of that class written to it. In addition you'll get the
list of prohibited codepoints.
Why bother with any kind of kernel modules? IDGI...
next prev parent reply other threads:[~2020-01-21 0:07 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-19 22:14 vfat: Broken case-insensitive support for UTF-8 Pali Rohár
2020-01-19 23:08 ` Al Viro
2020-01-19 23:33 ` Pali Rohár
2020-01-20 0:09 ` Al Viro
2020-01-20 11:19 ` Pali Rohár
2020-01-20 4:04 ` OGAWA Hirofumi
2020-01-20 7:30 ` Al Viro
2020-01-20 7:45 ` Al Viro
2020-01-20 8:07 ` oopsably broken case-insensitive support in ext4 and f2fs (Re: vfat: Broken case-insensitive support for UTF-8) Al Viro
2020-01-20 19:35 ` Al Viro
2020-01-24 4:29 ` Eric Biggers
2020-01-24 17:47 ` Linus Torvalds
2020-01-24 18:03 ` Jaegeuk Kim
2020-01-24 18:45 ` Eric Biggers
2020-01-20 11:04 ` vfat: Broken case-insensitive support for UTF-8 Pali Rohár
2020-01-20 12:07 ` OGAWA Hirofumi
2020-01-20 21:40 ` Pali Rohár
2020-01-20 22:46 ` Al Viro
2020-01-20 23:57 ` Pali Rohár
2020-01-21 0:07 ` Al Viro [this message]
2020-01-21 20:34 ` Pali Rohár
2020-01-21 21:36 ` Al Viro
2020-01-21 22:14 ` Al Viro
2020-01-21 22:46 ` Pali Rohár
2020-01-26 23:08 ` Pali Rohár
2020-01-21 12:43 ` David Laight
2020-01-22 0:25 ` Gabriel Krisman Bertazi
2020-01-20 15:07 ` David Laight
2020-01-20 15:20 ` Pali Rohár
2020-01-20 15:47 ` David Laight
2020-01-20 16:12 ` Al Viro
2020-01-20 16:51 ` David Laight
2020-01-20 16:27 ` Pali Rohár
2020-01-20 16:43 ` David Laight
2020-01-20 16:56 ` Pali Rohár
2020-01-20 17:37 ` Theodore Y. Ts'o
2020-01-20 17:32 ` Theodore Y. Ts'o
2020-01-20 17:56 ` Pali Rohár
2020-01-21 3:52 ` OGAWA Hirofumi
2020-01-21 11:00 ` Pali Rohár
2020-01-21 12:26 ` OGAWA Hirofumi
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