[PATCH v2] net/i40e: fix unintentional integer overflow

[Stephen Hemminger]

On Thu, 24 Feb 2022 01:17:22 +0000
Steve Yang <stevex.yang at intel.com> wrote:

> Cast 1 to type uint64_t to avoid overflow.
> 
> CID 375812 (#1 of 1):
> Unintentional integer overflow (OVERFLOW_BEFORE_WIDEN)
> overflow_before_widen: Potentially overflowing expression 1 << 2 * i + 1
> with type int (32 bits, signed) is evaluated using 32-bit arithmetic, and
> then used in a context that expects an expression of type uint64_t
> (64 bits, unsigned).
> 
> Coverity issue: 375812
> Fixes: 5fec01c35c49 ("net/i40e: support Linux VF to configure IRQ link list")
> Cc: stable at dpdk.org
> 
> ---
> v2: update commit message.
> 
> Signed-off-by: Steve Yang <stevex.yang at intel.com>
> ---
>  drivers/net/i40e/i40e_pf.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/i40e/i40e_pf.c b/drivers/net/i40e/i40e_pf.c
> index 2435a8a070..39e0c021a4 100644
> --- a/drivers/net/i40e/i40e_pf.c
> +++ b/drivers/net/i40e/i40e_pf.c
> @@ -604,7 +604,7 @@ i40e_pf_config_irq_link_list(struct i40e_pf_vf *vf,
>  	tempmap = vvm->txq_map;
>  	for (i = 0; i < sizeof(vvm->txq_map) * BITS_PER_CHAR; i++) {
>  		if (tempmap & 0x1)
> -			linklistmap |= (1 << (2 * i + 1));
> +			linklistmap |= ((uint64_t)1 << (2 * i + 1));

Could be RTE_BIT64(2 * i + 1) instead?