Re: [PATCH 4/7] Revert "ethtool: fix a potential missing-check bug"

[Greg Kroah-Hartman]

On Thu, Apr 29, 2021 at 03:08:08PM +0200, Greg Kroah-Hartman wrote:
> This reverts commit d656fe49e33df48ee6bc19e871f5862f49895c9e.
> 
> Commits from @umn.edu addresses have been found to be submitted in "bad
> faith" to try to test the kernel community's ability to review "known
> malicious" changes.  The result of these submissions can be found in a
> paper submitted to the 42nd IEEE Symposium on Security and Privacy
> entitled, "Open Source Insecurity: Stealthily Introducing
> Vulnerabilities via Hypocrite Commits" written by Qiushi Wu (University
> of Minnesota) and Kangjie Lu (University of Minnesota) but later
> withdrawn.
> 
> Because of this, all submissions from this group must be reverted from
> the kernel tree and will need to be re-reviewed again to determine if
> they actually are a valid fix.  Until that work is complete, remove this
> change to ensure that no problems are being introduced into the
> codebase.
> 
> Cc: Wenwen Wang <wang6495@xxxxxxx>
> Cc: David S. Miller <davem@xxxxxxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> ---
>  net/ethtool/ioctl.c | 5 -----
>  1 file changed, 5 deletions(-)
> 
> diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
> index 771688e1b0da..34688ebfd74e 100644
> --- a/net/ethtool/ioctl.c
> +++ b/net/ethtool/ioctl.c
> @@ -869,11 +869,6 @@ static noinline_for_stack int ethtool_get_rxnfc(struct net_device *dev,
>  		info_size = sizeof(info);
>  		if (copy_from_user(&info, useraddr, info_size))
>  			return -EFAULT;
> -		/* Since malicious users may modify the original data,
> -		 * we need to check whether FLOW_RSS is still requested.
> -		 */
> -		if (!(info.flow_type & FLOW_RSS))
> -			return -EINVAL;
>  	}
>  
>  	if (info.cmd != cmd)
> -- 
> 2.31.1
> 

This change looks correct, I'll drop the revert from my tree.

thanks,

greg k-h