Re: [dpdk-dev] [PATCH] net/bnxt: fix undefined shift in vers_get

[Somnath Kotur <somnath.kotur@broadcom.com>]

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On Wed, 3 Nov 2021, 02:57 Stephen Hemminger, <stephen@networkplumber.org>
wrote:

> UBSan testing revealed undefined shift here.
>
> The firmware returns the version in bytes; and shifting a 8 bit
> quantity here can lead to undefined behaviour or truncation.
> The fix is to promote the bytes to 32 bit before shifting.
>
> Bugzilla ID: 838
> Fixes: 9a891c1764ea ("net/bnxt: update HWRM to version 1.9.2")
> Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> ---
>  drivers/net/bnxt/bnxt_hwrm.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/bnxt/bnxt_hwrm.c b/drivers/net/bnxt/bnxt_hwrm.c
> index 82e89b7c8af7..f3d46bafd265 100644
> --- a/drivers/net/bnxt/bnxt_hwrm.c
> +++ b/drivers/net/bnxt/bnxt_hwrm.c
> @@ -1260,9 +1260,9 @@ int bnxt_hwrm_ver_get(struct bnxt *bp, uint32_t
> timeout)
>                 resp->hwrm_intf_upd_8b, resp->hwrm_fw_maj_8b,
>                 resp->hwrm_fw_min_8b, resp->hwrm_fw_bld_8b,
>                 resp->hwrm_fw_rsvd_8b);
> -       bp->fw_ver = (resp->hwrm_fw_maj_8b << 24) |
> -                    (resp->hwrm_fw_min_8b << 16) |
> -                    (resp->hwrm_fw_bld_8b << 8) |
> +       bp->fw_ver = ((uint32_t)resp->hwrm_fw_maj_8b << 24) |
> +                    ((uint32_t)resp->hwrm_fw_min_8b << 16) |
> +                    ((uint32_t)resp->hwrm_fw_bld_8b << 8) |
>                      resp->hwrm_fw_rsvd_8b;
>         PMD_DRV_LOG(INFO, "Driver HWRM version: %d.%d.%d\n",
>                 HWRM_VERSION_MAJOR, HWRM_VERSION_MINOR,
> HWRM_VERSION_UPDATE);
> --
> 2.30.2
>
Acked-by: Somnath Kotur <somnath.kotur@broadcom.com>

>
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