[PATCH net-next] ice: Fix off by one in ice_tc_forward_to_queue()

[PATCH net-next] ice: Fix off by one in ice_tc_forward_to_queue()

[Dan Carpenter]

The > comparison should be >= to prevent reading one element beyond
the end of the array.

The "vsi->num_rxq" is not strictly speaking the number of elements in
the vsi->rxq_map[] array.  The array has "vsi->alloc_rxq" elements and
"vsi->num_rxq" is less than or equal to the number of elements in the
array.  The array is allocated in ice_vsi_alloc_arrays().  It's still
an off by one but it might not access outside the end of the array.

Fixes: 143b86f346c7 ("ice: Enable RX queue selection using skbedit action")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
Applies to net-next.

 drivers/net/ethernet/intel/ice/ice_tc_lib.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_tc_lib.c b/drivers/net/ethernet/intel/ice/ice_tc_lib.c
index faba0f857cd9..95f392ab9670 100644
--- a/drivers/net/ethernet/intel/ice/ice_tc_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_tc_lib.c
@@ -1681,7 +1681,7 @@ ice_tc_forward_to_queue(struct ice_vsi *vsi, struct ice_tc_flower_fltr *fltr,
 	struct ice_vsi *ch_vsi = NULL;
 	u16 queue = act->rx_queue;
 
-	if (queue > vsi->num_rxq) {
+	if (queue >= vsi->num_rxq) {
 		NL_SET_ERR_MSG_MOD(fltr->extack,
 				   "Unable to add filter because specified queue is invalid");
 		return -EINVAL;
-- 
2.35.1

RE: [PATCH net-next] ice: Fix off by one in ice_tc_forward_to_queue()

[Nambiar, Amritha]

> -----Original Message-----
> From: Dan Carpenter <dan.carpenter@oracle.com>
> Sent: Friday, October 28, 2022 8:02 AM
> To: Brandeburg, Jesse <jesse.brandeburg@intel.com>; Nambiar, Amritha
> <amritha.nambiar@intel.com>
> Cc: Nguyen, Anthony L <anthony.l.nguyen@intel.com>; David S. Miller
> <davem@davemloft.net>; Eric Dumazet <edumazet@google.com>; Jakub
> Kicinski <kuba@kernel.org>; Paolo Abeni <pabeni@redhat.com>; Samudrala,
> Sridhar <sridhar.samudrala@intel.com>; Gomes, Vinicius
> <vinicius.gomes@intel.com>; intel-wired-lan@lists.osuosl.org;
> netdev@vger.kernel.org; kernel-janitors@vger.kernel.org
> Subject: [PATCH net-next] ice: Fix off by one in ice_tc_forward_to_queue()
> 
> The > comparison should be >= to prevent reading one element beyond
> the end of the array.
> 
> The "vsi->num_rxq" is not strictly speaking the number of elements in
> the vsi->rxq_map[] array.  The array has "vsi->alloc_rxq" elements and
> "vsi->num_rxq" is less than or equal to the number of elements in the
> array.  The array is allocated in ice_vsi_alloc_arrays().  It's still
> an off by one but it might not access outside the end of the array.
> 
> Fixes: 143b86f346c7 ("ice: Enable RX queue selection using skbedit action")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Acked-by: Amritha Nambiar <amritha.nambiar@intel.com>

> ---
> Applies to net-next.
> 
>  drivers/net/ethernet/intel/ice/ice_tc_lib.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/intel/ice/ice_tc_lib.c
> b/drivers/net/ethernet/intel/ice/ice_tc_lib.c
> index faba0f857cd9..95f392ab9670 100644
> --- a/drivers/net/ethernet/intel/ice/ice_tc_lib.c
> +++ b/drivers/net/ethernet/intel/ice/ice_tc_lib.c
> @@ -1681,7 +1681,7 @@ ice_tc_forward_to_queue(struct ice_vsi *vsi, struct
> ice_tc_flower_fltr *fltr,
>  	struct ice_vsi *ch_vsi = NULL;
>  	u16 queue = act->rx_queue;
> 
> -	if (queue > vsi->num_rxq) {
> +	if (queue >= vsi->num_rxq) {
>  		NL_SET_ERR_MSG_MOD(fltr->extack,
>  				   "Unable to add filter because specified
> queue is invalid");
>  		return -EINVAL;
> --
> 2.35.1