The x Bit Problem

The x Bit Problem

[Grant Miner]

An interesting thing I discovered is that Windows simply ignores the 'x' 
bit (I should say the Windows equivalent of the 'x' bit, called 
"traverse folder / execute file"), but there is a policy setting that 
overrides this attribute.

I know users get tripped up on this a lot in Unix, like when they don't 
understand why the webserver can't read their public_html directory.  It 
might be a good option for Linux.

Re: The x Bit Problem

[Bob]

Grant Miner wrote:

> An interesting thing I discovered is that Windows simply ignores the 
> 'x' bit (I should say the Windows equivalent of the 'x' bit, called 
> "traverse folder / execute file"), but there is a policy setting that 
> overrides this attribute.
>
> I know users get tripped up on this a lot in Unix, like when they 
> don't understand why the webserver can't read their public_html 
> directory.  It might be a good option for Linux.
>
> -
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>
Windows doesn't just ignore it. When I move
files from win to linux all the x bits are turned
on so txt and bz2 and jpg files are marked
executable. That's annoying and a security
risk.

-Bob

Re: The x Bit Problem

[Tomasz Rola]

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On Fri, 5 Dec 2003, Bob wrote:

> Windows doesn't just ignore it. When I move
> files from win to linux all the x bits are turned
> on so txt and bz2 and jpg files are marked
> executable. That's annoying and a security
> risk.

I'm jumping into this thread so this might have already been told but how
about umask=0111 mount option for dos (fat,vfat etc) filesystems? Also,
one may mount nodev, noexec and nosuid when appropriate. This, of course,
is not remedy, just a little painkiller.

bye
T.

- --
** A C programmer asked whether computer had Buddha's nature.      **
** As the answer, master did "rm -rif" on the programmer's home    **
** directory. And then the C programmer became enlightened...      **
**                                                                 **
** Tomasz Rola          mailto:tomasz_rola@bigfoot.com             **


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Re: The x Bit Problem

[Tomasz Rola]

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On Fri, 5 Dec 2003, Tomasz Rola wrote:

> On Fri, 5 Dec 2003, Bob wrote:
> 
> > Windows doesn't just ignore it. When I move
> > files from win to linux all the x bits are turned
> > on so txt and bz2 and jpg files are marked
> > executable. That's annoying and a security
> > risk.
> 
> I'm jumping into this thread so this might have already been told but how
> about umask=0111 mount option for dos (fat,vfat etc) filesystems? Also,

And I'm answering to myself.

Nope. But with showexec=no it seems that only dirs and *.exe are x-ed.
Writing faster than light isn't good because humans think slower than
light...

bye
T.

- --
** A C programmer asked whether computer had Buddha's nature.      **
** As the answer, master did "rm -rif" on the programmer's home    **
** directory. And then the C programmer became enlightened...      **
**                                                                 **
** Tomasz Rola          mailto:tomasz_rola@bigfoot.com             **


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Re: The x Bit Problem

[Hans Reiser]

Grant Miner wrote:

> An interesting thing I discovered is that Windows simply ignores the 
> 'x' bit (I should say the Windows equivalent of the 'x' bit, called 
> "traverse folder / execute file"), but there is a policy setting that 
> overrides this attribute.
>
> I know users get tripped up on this a lot in Unix, like when they 
> don't understand why the webserver can't read their public_html 
> directory.  It might be a good option for Linux.
>
>
>
The right solution is to have a separate readdir permission, so that a 
file-directory can be not executable but be listable, and vice-versa.  
The problem comes from overloading the bit and also changing whether 
objects can be simultaneously files and directories.

-- 
Hans