Re: [PATCH v2] cxgb4: add forgotten u64 ivlan cast before shift

[Jacob Keller]

On 8/19/2024 12:54 AM, Nikolay Kuratov wrote:
> It is done everywhere in cxgb4 code, e.g. in is_filter_exact_match()
> There is no reason it should not be done here
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE
> 

Without casting to u64, the value would be smaller and the shift might
not behave as expected?

Slightly annoying that the extra cause causes us to break 80 columns.

I checked and the FT_VLAN_VLD_F doesn't appear to already be a ULL value
either.

Reviewed-by: Jacob Keller <jacob.e.keller@xxxxxxxxx>

> Signed-off-by: Nikolay Kuratov <kniv@xxxxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 12b276fbf6e0 ("cxgb4: add support to create hash filters")
> Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
> ---
> v2: Wrap line to 80 characters
> 
>  drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c
> index 786ceae34488..dd9e68465e69 100644
> --- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c
> +++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c
> @@ -1244,7 +1244,8 @@ static u64 hash_filter_ntuple(struct ch_filter_specification *fs,
>  	 * in the Compressed Filter Tuple.
>  	 */
>  	if (tp->vlan_shift >= 0 && fs->mask.ivlan)
> -		ntuple |= (FT_VLAN_VLD_F | fs->val.ivlan) << tp->vlan_shift;
> +		ntuple |= (u64)(FT_VLAN_VLD_F |
> +				fs->val.ivlan) << tp->vlan_shift;
>  
>  	if (tp->port_shift >= 0 && fs->mask.iport)
>  		ntuple |= (u64)fs->val.iport << tp->port_shift;