Re: [PATCH] net: sfc: fix possible buffer overflow caused by bad DMA value in efx_siena_sriov_vfdi()

From: Edward Cree
Date: Mon Aug 03 2020 - 16:47:10 EST


On 02/08/2020 16:39, Jia-Ju Bai wrote:
> To fix this problem, "req->op" is assigned to a local variable, and then
> the driver accesses this variable instead of "req->op".
>
> Signed-off-by: Jia-Ju Bai <baijiaju@xxxxxxxxxxxxxxx>
Not sure how necessary this is (or even if anyone's still usingSiena
 SR-IOV, since it needed a specially-patched libvirt to work), but I
 don't see any reason to refuse.
> diff --git a/drivers/net/ethernet/sfc/siena_sriov.c b/drivers/net/ethernet/sfc/siena_sriov.c
> index 83dcfcae3d4b..21a8482cbb3b 100644
> --- a/drivers/net/ethernet/sfc/siena_sriov.c
> +++ b/drivers/net/ethernet/sfc/siena_sriov.c
> @@ -875,6 +875,7 @@ static void efx_siena_sriov_vfdi(struct work_struct *work)
> struct vfdi_req *req = vf->buf.addr;
> struct efx_memcpy_req copy[2];
> int rc;
> + u32 op = req->op;
Could you maybe fix up the xmas here, rather than making it worse?

Also, you didn't specify in your Subject line which tree this is for.

-ed