Re: [PATCH] net: thunderx: nicvf_main: Fix potential NULL pointer dereference

From: Eric Dumazet
Date: Tue Apr 03 2018 - 17:47:44 EST




On 04/03/2018 02:29 PM, Gustavo A. R. Silva wrote:
> Add null check on kmalloc() return value in order to prevent
> a null pointer dereference.
>
> Addresses-Coverity-ID: 1467429 ("Dereference null return value")
> Fixes: 37c3347eb247 ("net: thunderx: add ndo_set_rx_mode callback implementation for VF")
> Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
> ---
> drivers/net/ethernet/cavium/thunder/nicvf_main.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_main.c b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
> index 1e9a31f..468321a 100644
> --- a/drivers/net/ethernet/cavium/thunder/nicvf_main.c
> +++ b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
> @@ -1999,6 +1999,8 @@ static void nicvf_set_rx_mode(struct net_device *netdev)
> struct xcast_addr *xaddr;
>
> mc_list = kmalloc(sizeof(*mc_list), GFP_ATOMIC);
> + if (unlikely(!mc_list))
> + return;
> INIT_LIST_HEAD(&mc_list->list);
> netdev_hw_addr_list_for_each(ha, &netdev->mc) {
> xaddr = kmalloc(sizeof(*xaddr),
>

What about the second kmalloc() right there ?