Re: Make mv work better with SELinux.

[Jim Meyering]

Pádraig Brady wrote:

> On 10/08/2012 09:24 PM, Daniel J Walsh wrote:
>> -----BEGIN PGP SIGNED MESSAGE-----
>> Hash: SHA1
>>
>> One of if not the most common problem people hit with SELinux is the mv
>> command, which maintains the file context of the source destination.
>>
>> mv /home/dwalsh/index.html /var/www/html/
>>
>> This blows up on everybody and then the users have no idea why.
>>
>> I was thinking about adding -Z (--restorecon) to mv and having it basically 
>> do a
>> internal restorecon on the destination.
>>
>> Then we could suggest people who get burnt by this to:
>>
>> alias mv="mv -Z"
>>
>> In Fedora 18 we have greatly enhanced matchpathcon, by pre-compiling the
>> regex, so there should be very little slow down in doing this.
>>
>> I will work on the patch, if people agree with the idea.
>
> I like the idea.
> Now cp and install should behave similarly,
> and they already have the -Z option.

Upstream cp does not have -Z.
I agree that this seems like the right time to add it.

> So I would suggest that cp, mv and install
> support the -Z option without an argument,
> which means auto set the context based on the destination.
>
> The caveat with that is that short options
> with optional args are very problematic.
> So I'd just have the long --context have
> an optional arg, while -Z would require an arg.

[in a follow-up]
> Thinking further, --context without an option,
> is not too clear to the user. They might think
> they were copying the original context rather
> than setting a new context.

> Pity the long option wasn't called --new-context.
> I suppose we could have that as an alias for --context
> and deprecate the former?

Sounds reasonable.
Adjust the other --context=CTX commands, mkdir, mkfifo, mknod
at the same time.