bnx2x: Fix potential infinite loop

From: Colin Ian King <colin.king@canonical.com>

The for_each_tx_queue loop iterates with a u8 loop counter i and
compares this with the loop upper limit of bp->num_queues that
is an int type.  There is a potential infinite loop if bp->num_queues
is larger than the u8 loop counter. Fix this by making the loop
counter the same type as bp->num_queues.

Addresses-Coverity: ("Infinite loop")
Fixes: ad5afc89365e ("bnx2x: Separate VF and PF logic")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

> -----Original Message-----

> From: Colin King <colin.king@canonical.com>

> Sent: Wednesday, April 7, 2021 7:58 PM

> To: Ariel Elior <aelior@marvell.com>; Sudarsana Reddy Kalluru

> <skalluru@marvell.com>; GR-everest-linux-l2 <GR-everest-linux-

> l2@marvell.com>; David S . Miller <davem@davemloft.net>; Jakub Kicinski

> <kuba@kernel.org>; Eilon Greenstein <eilong@broadcom.com>;

> netdev@vger.kernel.org

> Cc: kernel-janitors@vger.kernel.org; linux-kernel@vger.kernel.org

> Subject: [EXT] [PATCH] bnx2x: Fix potential infinite loop

> 

> External Email

> 

> ----------------------------------------------------------------------

> From: Colin Ian King <colin.king@canonical.com>

> 

> The for_each_tx_queue loop iterates with a u8 loop counter i and compares

> this with the loop upper limit of bp->num_queues that is an int type.  There

> is a potential infinite loop if bp->num_queues is larger than the u8 loop

> counter. Fix this by making the loop counter the same type as bp-

> >num_queues.

> 

> Addresses-Coverity: ("Infinite loop")

> Fixes: ad5afc89365e ("bnx2x: Separate VF and PF logic")

> Signed-off-by: Colin Ian King <colin.king@canonical.com>

> ---

>  drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c | 3 ++-

>  1 file changed, 2 insertions(+), 1 deletion(-)

> 

> diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c

> b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c

> index 1a6ec1a12d53..edfbeb710ad4 100644

> --- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c

> +++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c

> @@ -2959,7 +2959,8 @@ int bnx2x_nic_load(struct bnx2x *bp, int

> load_mode)

> 

>  int bnx2x_drain_tx_queues(struct bnx2x *bp)  {

> -	u8 rc = 0, cos, i;

> +	u8 rc = 0, cos;

> +	int i;

> 

>  	/* Wait until tx fastpath tasks complete */

>  	for_each_tx_queue(bp, i) {

> --

> 2.30.2


Thanks for the change. [just for the info, theoretical max num_queues value for bnx2x device is 33]

Acked-by: Sudarsana Reddy Kalluru <skalluru@marvell.com>