From: Mitch Williams Date: Thu, 12 Dec 2019 11:13:05 +0000 (-0800) Subject: ice: add extra check for null Rx descriptor X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=1f45ebe0d8fbe6178670b663005f38ef8535db5d;p=uclinux-h8%2Flinux.git ice: add extra check for null Rx descriptor In the case where the hardware gives us a null Rx descriptor, it is theoretically possible that we could call one of our skb-construction functions with no data pointer, which would cause a panic. In real life, this will never happen - we only get null RX descriptors as the final descriptor in a chain of otherwise-valid descriptors. When this happens, the skb will be extant and we'll just call ice_add_rx_frag(), which can deal with empty data buffers. Unfortunately, Coverity does not have intimate knowledge of our hardware, so we must add a check here. Signed-off-by: Mitch Williams Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher --- diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c index b77514bbd7ba..fd17ace6b226 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx.c +++ b/drivers/net/ethernet/intel/ice/ice_txrx.c @@ -1071,13 +1071,16 @@ static int ice_clean_rx_irq(struct ice_ring *rx_ring, int budget) ice_put_rx_buf(rx_ring, rx_buf); continue; construct_skb: - if (skb) + if (skb) { ice_add_rx_frag(rx_ring, rx_buf, skb, size); - else if (ice_ring_uses_build_skb(rx_ring)) - skb = ice_build_skb(rx_ring, rx_buf, &xdp); - else + } else if (likely(xdp.data)) { + if (ice_ring_uses_build_skb(rx_ring)) + skb = ice_build_skb(rx_ring, rx_buf, &xdp); + else + skb = ice_construct_skb(rx_ring, rx_buf, &xdp); + } else { skb = ice_construct_skb(rx_ring, rx_buf, &xdp); - + } /* exit if we failed to retrieve a buffer */ if (!skb) { rx_ring->rx_stats.alloc_buf_failed++;