From: Robert Hancock <robert.hancock@xxxxxxxxxx> commit 70f5817deddbc6ef3faa35841cab83c280cc653a upstream. The driver will not work properly if the TX ring size is set to below MAX_SKB_FRAGS + 1 since it needs to hold at least one full maximally fragmented packet in the TX ring. Limit setting the ring size to below this value. Fixes: 8b09ca823ffb4 ("net: axienet: Make RX/TX ring sizes configurable") Signed-off-by: Robert Hancock <robert.hancock@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c @@ -43,6 +43,7 @@ /* Descriptors defines for Tx and Rx DMA */ #define TX_BD_NUM_DEFAULT 64 #define RX_BD_NUM_DEFAULT 1024 +#define TX_BD_NUM_MIN (MAX_SKB_FRAGS + 1) #define TX_BD_NUM_MAX 4096 #define RX_BD_NUM_MAX 4096 @@ -1223,7 +1224,8 @@ static int axienet_ethtools_set_ringpara if (ering->rx_pending > RX_BD_NUM_MAX || ering->rx_mini_pending || ering->rx_jumbo_pending || - ering->rx_pending > TX_BD_NUM_MAX) + ering->tx_pending < TX_BD_NUM_MIN || + ering->tx_pending > TX_BD_NUM_MAX) return -EINVAL; if (netif_running(ndev))