From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paul Moore <paul.moore@hp.com>
To: Eric Paris <eparis@redhat.com>
Subject: Re: [PATCH 1/2] SELinux: NULL terminate al contexts from disk
Date: Thu, 12 Feb 2009 15:46:56 -0500
Cc: selinux@tycho.nsa.gov, sds@tycho.nsa.gov, jmorris@namei.org
References: <20090212195005.25556.94754.stgit@paris.rdu.redhat.com>
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On Thursday 12 February 2009 02:50:05 pm Eric Paris wrote:
> @@ -1290,12 +1290,13 @@ static int inode_doinit_with_dentry(struct inode
> *inode, struct dentry *opt_dent }
>
>  		len = INITCONTEXTLEN;
> -		context = kmalloc(len, GFP_NOFS);
> +		context = kmalloc(len+1, GFP_NOFS);
>  		if (!context) {
>  			rc = -ENOMEM;
>  			dput(dentry);
>  			goto out_unlock;
>  		}
> +		context[len] = '\0';
>  		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
>  					   context, len);
>  		if (rc == -ERANGE) {

Perhaps move the "context[len] = '\0';" to just after the getxattr() call?  It 
might help provide a little extra protection in case getxattr() gets a little 
buggy ... then again maybe not, your call.

-- 
paul moore
linux @ hp


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