[Acked] [PATCH Quantal/Raring SRU] Smack: Fix the bug smackcipso can't set CIPSO correctly

[Andy Whitcroft]

On Tue, Oct 08, 2013 at 08:23:38AM -0600, Tim Gardner wrote:
> From: "Passion,Zhao" <passion.zhao at intel.com>
> 
> BugLink: http://bugs.launchpad.net/bugs/1236743
> 
> Bug report: https://tizendev.org/bugs/browse/TDIS-3891
> 
> The reason is userspace libsmack only use "smackfs/cipso2" long-label interface,
> but the code's logical is still for orginal fixed length label. Now update
> smack_cipso_apply() to support flexible label (<=256 including tailing '\0')
> 
> There is also a bug in kernel/security/smack/smackfs.c:
> When smk_set_cipso() parsing the CIPSO setting from userspace, the offset of
> CIPSO level should be "strlen(label)+1" instead of "strlen(label)"
> 
> Signed-off-by: Passion,Zhao <passion.zhao at intel.com>
> (cherry picked from commit 0fcfee61d63b82c1eefb5b1a914240480f17d63f)
> Signed-off-by: Tim Gardner <tim.gardner at canonical.com>
> ---
> 
> This seems like a good candidate for stable 3.5 - 3.10
> 
>  security/smack/smackfs.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c
> index 76a5dca..c4fe705 100644
> --- a/security/smack/smackfs.c
> +++ b/security/smack/smackfs.c
> @@ -818,7 +818,7 @@ static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
>  	if (format == SMK_FIXED24_FMT)
>  		rule += SMK_LABELLEN;
>  	else
> -		rule += strlen(skp->smk_known);
> +		rule += strlen(skp->smk_known) + 1;
>  
>  	ret = sscanf(rule, "%d", &maplevel);
>  	if (ret != 1 || maplevel > SMACK_CIPSO_MAXLEVEL)

Looks to make sense, else we will also sscanf against the \0 of the
string in the variable case.

Acked-by: Andy Whitcroft <apw at canonical.com>

-apw