bpf: do not WARN in bpf_warn_invalid_xdp_action()

PATCH Superseded Paolo Abeni 2 participants 5 messages Nov 19, 2021 – Nov 24, 2021

Subsystems (30)

Networking Network drivers BPF Arm STM32 +26 more subsystems

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Paolo Abeni

author maintainer

2021-11-19 16:40 UTC #0 lore raw

cover bpf: do not WARN in bpf_warn_invalid_xdp_action()

The mentioned WARN is quite noisy, especially vs fuzzers and apparently used only to track the relevant BPF program and/or involved driver.

The first patch replace it with a pr_warn_once(), and the 2nd patch allow dumps relevant info to track the reported issue.

This is quite invasive, but the mentioned WARN makes the hunt for some bugs reported by syzkaller quite difficult.

Paolo Abeni (2):
bpf: do not WARN in bpf_warn_invalid_xdp_action()
bpf: let bpf_warn_invalid_xdp_action() report more info

 drivers/net/ethernet/amazon/ena/ena_netdev.c           | 2 +-
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c          | 2 +-
 drivers/net/ethernet/cavium/thunder/nicvf_main.c       | 2 +-
 drivers/net/ethernet/freescale/dpaa/dpaa_eth.c         | 2 +-
 drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c       | 2 +-
 drivers/net/ethernet/freescale/enetc/enetc.c           | 2 +-
 drivers/net/ethernet/intel/i40e/i40e_txrx.c            | 2 +-
 drivers/net/ethernet/intel/i40e/i40e_xsk.c             | 2 +-
 drivers/net/ethernet/intel/ice/ice_txrx.c              | 2 +-
 drivers/net/ethernet/intel/ice/ice_xsk.c               | 2 +-
 drivers/net/ethernet/intel/igb/igb_main.c              | 2 +-
 drivers/net/ethernet/intel/igc/igc_main.c              | 2 +-
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c          | 2 +-
 drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c           | 2 +-
 drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c      | 2 +-
 drivers/net/ethernet/marvell/mvneta.c                  | 2 +-
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c        | 2 +-
 drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.c | 2 +-
 drivers/net/ethernet/mellanox/mlx4/en_rx.c             | 2 +-
 drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c       | 2 +-
 drivers/net/ethernet/netronome/nfp/nfp_net_common.c    | 2 +-
 drivers/net/ethernet/qlogic/qede/qede_fp.c             | 2 +-
 drivers/net/ethernet/sfc/rx.c                          | 2 +-
 drivers/net/ethernet/socionext/netsec.c                | 2 +-
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c      | 2 +-
 drivers/net/ethernet/ti/cpsw_priv.c                    | 2 +-
 drivers/net/hyperv/netvsc_bpf.c                        | 2 +-
 drivers/net/tun.c                                      | 2 +-
 drivers/net/veth.c                                     | 4 ++--
 drivers/net/virtio_net.c                               | 4 ++--
 drivers/net/xen-netfront.c                             | 2 +-
 include/linux/filter.h                                 | 2 +-
 kernel/bpf/cpumap.c                                    | 4 ++--
 kernel/bpf/devmap.c                                    | 4 ++--
 net/core/dev.c                                         | 2 +-
 net/core/filter.c                                      | 8 ++++----
 36 files changed, 43 insertions(+), 43 deletions(-)

Signature · 1 line

2.33.1

Paolo Abeni

author maintainer

2021-11-19 16:40 UTC #1 lore raw

PATCH 1/2 bpf: do not WARN in bpf_warn_invalid_xdp_action()

The WARN_ONCE() in bpf_warn_invalid_xdp_action() can be triggered by any bugged program, and even attaching a correct program to a NIC not supporting the given action.

The resulting splat, beyond polluting the logs, fouls automated tools:
e.g. a syzkaller reproducers using an XDP program returning an unsupported action will never pass validation.

Replace the WARN_ONCE with a less intrusive pr_warn_once().

Acked-by Toke Høiland-Jørgensen <[email protected]>

Signed-off-by Paolo Abeni <[email protected]>

---
 net/core/filter.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

net/core/filter.c +3 -3

index e471c9b09670..3ba584bb23f8 100644
@@ -8183,9 +8183,9 @@ void bpf_warn_invalid_xdp_action(u32 act)
 {
 	const u32 act_max = XDP_REDIRECT;
 
-	WARN_ONCE(1, "%s XDP return value %u, expect packet loss!\n",
-		  act > act_max ? "Illegal" : "Driver unsupported",
-		  act);
+	pr_warn_once("%s XDP return value %u, expect packet loss!\n",
+		     act > act_max ? "Illegal" : "Driver unsupported",
+		     act);
 }
 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);

Signature · 1 line

2.33.1

Paolo Abeni

author maintainer

2021-11-19 16:40 UTC #2 lore raw

PATCH 2/2 bpf: let bpf_warn_invalid_xdp_action() report more info

In reply to Paolo Abeni

In non trivial scenarios, the action id alone is not sufficient to identify the program causing the warning. Before the previous patch, the generated stack-trace pointed out at least the involved device driver.

Let's additionally include the program name and id, and the relevant device name.

If the user needs additional infos, he can fetch them via a kernel probe, leveraging the arguments added here.

rfc -> v1:
- do not print the attach type, print the program name

Signed-off-by Paolo Abeni <[email protected]>

---
 drivers/net/ethernet/amazon/ena/ena_netdev.c           | 2 +-
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c          | 2 +-
 drivers/net/ethernet/cavium/thunder/nicvf_main.c       | 2 +-
 drivers/net/ethernet/freescale/dpaa/dpaa_eth.c         | 2 +-
 drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c       | 2 +-
 drivers/net/ethernet/freescale/enetc/enetc.c           | 2 +-
 drivers/net/ethernet/intel/i40e/i40e_txrx.c            | 2 +-
 drivers/net/ethernet/intel/i40e/i40e_xsk.c             | 2 +-
 drivers/net/ethernet/intel/ice/ice_txrx.c              | 2 +-
 drivers/net/ethernet/intel/ice/ice_xsk.c               | 2 +-
 drivers/net/ethernet/intel/igb/igb_main.c              | 2 +-
 drivers/net/ethernet/intel/igc/igc_main.c              | 2 +-
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c          | 2 +-
 drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c           | 2 +-
 drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c      | 2 +-
 drivers/net/ethernet/marvell/mvneta.c                  | 2 +-
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c        | 2 +-
 drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.c | 2 +-
 drivers/net/ethernet/mellanox/mlx4/en_rx.c             | 2 +-
 drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c       | 2 +-
 drivers/net/ethernet/netronome/nfp/nfp_net_common.c    | 2 +-
 drivers/net/ethernet/qlogic/qede/qede_fp.c             | 2 +-
 drivers/net/ethernet/sfc/rx.c                          | 2 +-
 drivers/net/ethernet/socionext/netsec.c                | 2 +-
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c      | 2 +-
 drivers/net/ethernet/ti/cpsw_priv.c                    | 2 +-
 drivers/net/hyperv/netvsc_bpf.c                        | 2 +-
 drivers/net/tun.c                                      | 2 +-
 drivers/net/veth.c                                     | 4 ++--
 drivers/net/virtio_net.c                               | 4 ++--
 drivers/net/xen-netfront.c                             | 2 +-
 include/linux/filter.h                                 | 2 +-
 kernel/bpf/cpumap.c                                    | 4 ++--
 kernel/bpf/devmap.c                                    | 4 ++--
 net/core/dev.c                                         | 2 +-
 net/core/filter.c                                      | 6 +++---
 36 files changed, 42 insertions(+), 42 deletions(-)

drivers/net/ethernet/amazon/ena/ena_netdev.c +1 -1

index 7d5d885d85d5..3b46f1df5609 100644
@@ -434,7 +434,7 @@ static int ena_xdp_execute(struct ena_ring *rx_ring, struct xdp_buff *xdp)
 		xdp_stat = &rx_ring->rx_stats.xdp_pass;
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(verdict);
+		bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, verdict);
 		xdp_stat = &rx_ring->rx_stats.xdp_invalid;
 	}

drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c +1 -1

index c8083df5e0ab..52fad0fdeacf 100644
@@ -195,7 +195,7 @@ bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons,
 		*event |= BNXT_REDIRECT_EVENT;
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(bp->dev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(bp->dev, xdp_prog, act);

drivers/net/ethernet/cavium/thunder/nicvf_main.c +1 -1

index bb45d5df2856..30450efccad7 100644
@@ -590,7 +590,7 @@ static inline bool nicvf_xdp_rx(struct nicvf *nic, struct bpf_prog *prog,
 		nicvf_xdp_sq_append_pkt(nic, sq, (u64)xdp.data, dma_addr, len);
 		return true;
 	default:
-		bpf_warn_invalid_xdp_action(action);
+		bpf_warn_invalid_xdp_action(nic->netdev, prog, action);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(nic->netdev, prog, action);

drivers/net/ethernet/freescale/dpaa/dpaa_eth.c +1 -1

index 6b2927d863e2..39fafb7d43b2 100644
@@ -2623,7 +2623,7 @@ static u32 dpaa_run_xdp(struct dpaa_priv *priv, struct qm_fd *fd, void *vaddr,
 		}
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(xdp_act);
+		bpf_warn_invalid_xdp_action(priv->net_dev, xdp_prog, xdp_act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(priv->net_dev, xdp_prog, xdp_act);

drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c +1 -1

index 714e961e7a77..f113469bd479 100644
@@ -374,7 +374,7 @@ static u32 dpaa2_eth_run_xdp(struct dpaa2_eth_priv *priv,
 		dpaa2_eth_xdp_enqueue(priv, ch, fd, vaddr, rx_fq->flowid);
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(xdp_act);
+		bpf_warn_invalid_xdp_action(priv->net_dev, xdp_prog, xdp_act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(priv->net_dev, xdp_prog, xdp_act);

drivers/net/ethernet/freescale/enetc/enetc.c +1 -1

index 504e12554079..eacb41f86bdb 100644
@@ -1547,7 +1547,7 @@ static int enetc_clean_rx_ring_xdp(struct enetc_bdr *rx_ring,
 
 		switch (xdp_act) {
 		default:
-			bpf_warn_invalid_xdp_action(xdp_act);
+			bpf_warn_invalid_xdp_action(rx_ring->ndev, prog, xdp_act);
 			fallthrough;
 		case XDP_ABORTED:
 			trace_xdp_exception(rx_ring->ndev, prog, xdp_act);

drivers/net/ethernet/intel/i40e/i40e_txrx.c +1 -1

index 10a83e5385c7..b399ca649f09 100644
@@ -2322,7 +2322,7 @@ static int i40e_run_xdp(struct i40e_ring *rx_ring, struct xdp_buff *xdp)
 		result = I40E_XDP_REDIR;
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 out_failure:

drivers/net/ethernet/intel/i40e/i40e_xsk.c +1 -1

index ea06e957393e..945b1bb9c6f4 100644
@@ -176,7 +176,7 @@ static int i40e_run_xdp_zc(struct i40e_ring *rx_ring, struct xdp_buff *xdp)
 			goto out_failure;
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 out_failure:

drivers/net/ethernet/intel/ice/ice_txrx.c +1 -1

index bc3ba19dc88f..56940bb908bc 100644
@@ -561,7 +561,7 @@ ice_run_xdp(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp,
 			goto out_failure;
 		return ICE_XDP_REDIR;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 out_failure:

drivers/net/ethernet/intel/ice/ice_xsk.c +1 -1

index ff55cb415b11..eb68a5824e9a 100644
@@ -482,7 +482,7 @@ ice_run_xdp_zc(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp,
 			goto out_failure;
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 out_failure:

drivers/net/ethernet/intel/igb/igb_main.c +1 -1

index 836be0d3b291..bdce483d4c0e 100644
@@ -8422,7 +8422,7 @@ static struct sk_buff *igb_run_xdp(struct igb_adapter *adapter,
 		result = IGB_XDP_REDIR;
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(adapter->netdev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 out_failure:

drivers/net/ethernet/intel/igc/igc_main.c +1 -1

index 8e448288ee26..4ea212ddcc9b 100644
@@ -2231,7 +2231,7 @@ static int __igc_xdp_run_prog(struct igc_adapter *adapter,
 		return IGC_XDP_REDIRECT;
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(adapter->netdev, prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 out_failure:

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +1 -1

index 0f9f022260d7..265bc52aacf8 100644
@@ -2235,7 +2235,7 @@ static struct sk_buff *ixgbe_run_xdp(struct ixgbe_adapter *adapter,
 		result = IXGBE_XDP_REDIR;
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 out_failure:

drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c +1 -1

index db2bc58dfcfd..b3fd8e5cd85b 100644
@@ -131,7 +131,7 @@ static int ixgbe_run_xdp_zc(struct ixgbe_adapter *adapter,
 			goto out_failure;
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 out_failure:

drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c +1 -1

index d81811ab4ec4..757fe0dace88 100644
@@ -1070,7 +1070,7 @@ static struct sk_buff *ixgbevf_run_xdp(struct ixgbevf_adapter *adapter,
 			goto out_failure;
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 out_failure:

drivers/net/ethernet/marvell/mvneta.c +1 -1

index 5a7bdca22a63..c457a765a828 100644
@@ -2212,7 +2212,7 @@ mvneta_run_xdp(struct mvneta_port *pp, struct mvneta_rx_queue *rxq,
 			mvneta_xdp_put_buff(pp, rxq, xdp, sinfo, sync);
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(pp->dev, prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(pp->dev, prog, act);

drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c +1 -1

index 2b18d89d9756..e7b7200af5c3 100644
@@ -3820,7 +3820,7 @@ mvpp2_run_xdp(struct mvpp2_port *port, struct bpf_prog *prog,
 		}
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(port->dev, prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(port->dev, prog, act);

drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.c +1 -1

index 0cc6353254bf..7c4068c5d1ac 100644
@@ -1198,7 +1198,7 @@ static bool otx2_xdp_rcv_pkt_handler(struct otx2_nic *pfvf,
 		put_page(page);
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(pfvf->netdev, prog, act);
 		break;
 	case XDP_ABORTED:
 		trace_xdp_exception(pfvf->netdev, prog, act);

drivers/net/ethernet/mellanox/mlx4/en_rx.c +1 -1

index 650e6a1844ae..8cfc649f226b 100644
@@ -812,7 +812,7 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
 				trace_xdp_exception(dev, xdp_prog, act);
 				goto xdp_drop_no_cnt; /* Drop on xmit failure */
 			default:
-				bpf_warn_invalid_xdp_action(act);
+				bpf_warn_invalid_xdp_action(dev, xdp_prog, act);
 				fallthrough;
 			case XDP_ABORTED:
 				trace_xdp_exception(dev, xdp_prog, act);

drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c +1 -1

index 2f0df5cc1a2d..338d65e2c9ce 100644
@@ -151,7 +151,7 @@ bool mlx5e_xdp_handle(struct mlx5e_rq *rq, struct mlx5e_dma_info *di,
 		rq->stats->xdp_redirect++;
 		return true;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(rq->netdev, prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 xdp_abort:

drivers/net/ethernet/netronome/nfp/nfp_net_common.c +1 -1

index 850bfdf83d0a..56ef3d64e30d 100644
@@ -1944,7 +1944,7 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget)
 							    xdp_prog, act);
 				continue;
 			default:
-				bpf_warn_invalid_xdp_action(act);
+				bpf_warn_invalid_xdp_action(dp->netdev, xdp_prog, act);
 				fallthrough;
 			case XDP_ABORTED:
 				trace_xdp_exception(dp->netdev, xdp_prog, act);

drivers/net/ethernet/qlogic/qede/qede_fp.c +1 -1

index 065e9004598e..32c6e14814bb 100644
@@ -1152,7 +1152,7 @@ static bool qede_rx_xdp(struct qede_dev *edev,
 		qede_rx_bd_ring_consume(rxq);
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(edev->ndev, prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(edev->ndev, prog, act);

drivers/net/ethernet/sfc/rx.c +1 -1

index 606750938b89..2375cef577e4 100644
@@ -338,7 +338,7 @@ static bool efx_do_xdp(struct efx_nic *efx, struct efx_channel *channel,
 		break;
 
 	default:
-		bpf_warn_invalid_xdp_action(xdp_act);
+		bpf_warn_invalid_xdp_action(efx->net_dev, xdp_prog, xdp_act);
 		efx_free_rx_buffers(rx_queue, rx_buf, 1);
 		channel->n_rx_xdp_bad_drops++;
 		trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act);

drivers/net/ethernet/socionext/netsec.c +1 -1

index de7d8bf2c226..25dcd8eda5fc 100644
@@ -933,7 +933,7 @@ static u32 netsec_run_xdp(struct netsec_priv *priv, struct bpf_prog *prog,
 		}
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(priv->ndev, prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(priv->ndev, prog, act);

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +1 -1

index d3f350c25b9b..4cb34001c9ac 100644
@@ -4690,7 +4690,7 @@ static int __stmmac_xdp_run_prog(struct stmmac_priv *priv,
 			res = STMMAC_XDP_REDIRECT;
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(priv->dev, prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(priv->dev, prog, act);

drivers/net/ethernet/ti/cpsw_priv.c +1 -1

index ecc2a6b7e28f..e9fdf60ba1a8 100644
@@ -1360,7 +1360,7 @@ int cpsw_run_xdp(struct cpsw_priv *priv, int ch, struct xdp_buff *xdp,
 		xdp_do_flush_map();
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(ndev, prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(ndev, prog, act);

drivers/net/hyperv/netvsc_bpf.c +1 -1

index aa877da113f8..7856905414eb 100644
@@ -68,7 +68,7 @@ u32 netvsc_run_xdp(struct net_device *ndev, struct netvsc_channel *nvchan,
 		break;
 
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(ndev, prog, act);
 	}
 
 out:

drivers/net/tun.c +1 -1

index fecc9a1d293a..0d47d34ba4e7 100644
@@ -1546,7 +1546,7 @@ static int tun_xdp_act(struct tun_struct *tun, struct bpf_prog *xdp_prog,
 	case XDP_PASS:
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(tun->dev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(tun->dev, xdp_prog, act);

drivers/net/veth.c +2 -2

index 50eb43e5bf45..f64dbd8b6403 100644
@@ -651,7 +651,7 @@ static struct xdp_frame *veth_xdp_rcv_one(struct veth_rq *rq,
 			rcu_read_unlock();
 			goto xdp_xmit;
 		default:
-			bpf_warn_invalid_xdp_action(act);
+			bpf_warn_invalid_xdp_action(rq->dev, xdp_prog, act);
 			fallthrough;
 		case XDP_ABORTED:
 			trace_xdp_exception(rq->dev, xdp_prog, act);

@@ -801,7 +801,7 @@ static struct sk_buff *veth_xdp_rcv_skb(struct veth_rq *rq,
 		rcu_read_unlock();
 		goto xdp_xmit;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(rq->dev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(rq->dev, xdp_prog, act);

drivers/net/virtio_net.c +2 -2

index 1771d6e5224f..105cd413df52 100644
@@ -812,7 +812,7 @@ static struct sk_buff *receive_small(struct net_device *dev,
 			rcu_read_unlock();
 			goto xdp_xmit;
 		default:
-			bpf_warn_invalid_xdp_action(act);
+			bpf_warn_invalid_xdp_action(vi->dev, xdp_prog, act);
 			fallthrough;
 		case XDP_ABORTED:
 			trace_xdp_exception(vi->dev, xdp_prog, act);

@@ -1025,7 +1025,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
 			rcu_read_unlock();
 			goto xdp_xmit;
 		default:
-			bpf_warn_invalid_xdp_action(act);
+			bpf_warn_invalid_xdp_action(vi->dev, xdp_prog, act);
 			fallthrough;
 		case XDP_ABORTED:
 			trace_xdp_exception(vi->dev, xdp_prog, act);

drivers/net/xen-netfront.c +1 -1

index 911f43986a8c..7b7eb617051a 100644
@@ -930,7 +930,7 @@ static u32 xennet_run_xdp(struct netfront_queue *queue, struct page *pdata,
 		break;
 
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(queue->info->netdev, prog, act);
 	}
 
 	return act;

include/linux/filter.h +1 -1

index 24b7ed2677af..c21d14fe0156 100644
@@ -1030,7 +1030,7 @@ void xdp_do_flush(void);
  */
 #define xdp_do_flush_map xdp_do_flush
 
-void bpf_warn_invalid_xdp_action(u32 act);
+void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act);
 
 #ifdef CONFIG_INET
 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,

kernel/bpf/cpumap.c +2 -2

index 585b2b77ccc4..f7359bcb8fa3 100644
@@ -195,7 +195,7 @@ static void cpu_map_bpf_prog_run_skb(struct bpf_cpu_map_entry *rcpu,
 			}
 			return;
 		default:
-			bpf_warn_invalid_xdp_action(act);
+			bpf_warn_invalid_xdp_action(skb->dev, rcpu->prog, act);
 			fallthrough;
 		case XDP_ABORTED:
 			trace_xdp_exception(skb->dev, rcpu->prog, act);

@@ -254,7 +254,7 @@ static int cpu_map_bpf_prog_run_xdp(struct bpf_cpu_map_entry *rcpu,
 			}
 			break;
 		default:
-			bpf_warn_invalid_xdp_action(act);
+			bpf_warn_invalid_xdp_action(xdpf->dev_rx, rcpu->prog, act);
 			fallthrough;
 		case XDP_DROP:
 			xdp_return_frame(xdpf);

kernel/bpf/devmap.c +2 -2

index f02d04540c0c..79bcf2169881 100644
@@ -348,7 +348,7 @@ static int dev_map_bpf_prog_run(struct bpf_prog *xdp_prog,
 				frames[nframes++] = xdpf;
 			break;
 		default:
-			bpf_warn_invalid_xdp_action(act);
+			bpf_warn_invalid_xdp_action(dev, xdp_prog, act);
 			fallthrough;
 		case XDP_ABORTED:
 			trace_xdp_exception(dev, xdp_prog, act);

@@ -507,7 +507,7 @@ static u32 dev_map_bpf_prog_run_skb(struct sk_buff *skb, struct bpf_dtab_netdev
 		__skb_push(skb, skb->mac_len);
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(dst->dev, dst->xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(dst->dev, dst->xdp_prog, act);

net/core/dev.c +1 -1

index 15ac064b5562..cf2691d17dd2 100644
@@ -4824,7 +4824,7 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
 	case XDP_PASS:
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(skb->dev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(skb->dev, xdp_prog, act);

net/core/filter.c +3 -3

index 3ba584bb23f8..658f7a84d9bc 100644
@@ -8179,13 +8179,13 @@ static bool xdp_is_valid_access(int off, int size,
 	return __is_valid_xdp_access(off, size);
 }
 
-void bpf_warn_invalid_xdp_action(u32 act)
+void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act)
 {
 	const u32 act_max = XDP_REDIRECT;
 
-	pr_warn_once("%s XDP return value %u, expect packet loss!\n",
+	pr_warn_once("%s XDP return value %u on prog %s (id %d) dev %s, expect packet loss!\n",
 		     act > act_max ? "Illegal" : "Driver unsupported",
-		     act);
+		     act, prog->aux->name, prog->aux->id, dev->name);
 }
 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);

Signature · 1 line

2.33.1

Toke Høiland-Jørgensen

2021-11-22 11:32 UTC #3 lore raw

Re: [PATCH net-next 2/2] bpf: let bpf_warn_invalid_xdp_action() report more info

You still have:

Quoted 36 lines

kernel/bpf/cpumap.c +2 -2

index 585b2b77ccc4..f7359bcb8fa3 100644
@@ -195,7 +195,7 @@ static void cpu_map_bpf_prog_run_skb(struct bpf_cpu_map_entry *rcpu,
 			}
 			return;
 		default:
-			bpf_warn_invalid_xdp_action(act);
+			bpf_warn_invalid_xdp_action(skb->dev, rcpu->prog, act);
 			fallthrough;
 		case XDP_ABORTED:
 			trace_xdp_exception(skb->dev, rcpu->prog, act);

@@ -254,7 +254,7 @@ static int cpu_map_bpf_prog_run_xdp(struct bpf_cpu_map_entry *rcpu,
 			}
 			break;
 		default:
-			bpf_warn_invalid_xdp_action(act);
+			bpf_warn_invalid_xdp_action(xdpf->dev_rx, rcpu->prog, act);
 			fallthrough;
 		case XDP_DROP:
 			xdp_return_frame(xdpf);

kernel/bpf/devmap.c +1 -1

index f02d04540c0c..79bcf2169881 100644
@@ -348,7 +348,7 @@ static int dev_map_bpf_prog_run(struct bpf_prog *xdp_prog,
 				frames[nframes++] = xdpf;
 			break;
 		default:
-			bpf_warn_invalid_xdp_action(act);
+			bpf_warn_invalid_xdp_action(dev, xdp_prog, act);
 			fallthrough;
 		case XDP_ABORTED:
 			trace_xdp_exception(dev, xdp_prog, act);

kernel/bpf/devmap.c static u32 dev_map_bpf_prog_run_skb(struct sk_buff *skb, struct bpf_dtab_netdev · line 513

Quoted 8 lines

kernel/bpf/devmap.c +1 -1

@@ -507,7 +507,7 @@ static u32 dev_map_bpf_prog_run_skb(struct sk_buff *skb, struct bpf_dtab_netdev
 		__skb_push(skb, skb->mac_len);
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(dst->dev, dst->xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(dst->dev, dst->xdp_prog, act);

... and ...

Quoted 10 lines

net/core/filter.c +1 -1

index 3ba584bb23f8..658f7a84d9bc 100644
@@ -8179,13 +8179,13 @@ static bool xdp_is_valid_access(int off, int size,
 	return __is_valid_xdp_access(off, size);
 }
 
-void bpf_warn_invalid_xdp_action(u32 act)
+void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act)

net/core/filter.c static bool xdp_is_valid_access(int off, int size, · line 8190

Quoted 10 lines

net/core/filter.c +2 -2

 {
 	const u32 act_max = XDP_REDIRECT;
 
-	pr_warn_once("%s XDP return value %u, expect packet loss!\n",
+	pr_warn_once("%s XDP return value %u on prog %s (id %d) dev %s, expect packet loss!\n",
 		     act > act_max ? "Illegal" : "Driver unsupported",
-		     act);
+		     act, prog->aux->name, prog->aux->id, dev->name);
 }
 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);

This will still print the dev name for cpumap and devmap programs, which is misleading - it will have people looking at the drivers when the problem is somewhere else.

I pointed this out multiple times in comments on your last revision so I'm a bit puzzled as to why you're still doing this? :/

Just pass NULL as the dev from cpumap/devmap and don't print the dev name in this case...

-Toke

Paolo Abeni

author maintainer

2021-11-24 09:14 UTC #4 lore raw

Re: [PATCH net-next 2/2] bpf: let bpf_warn_invalid_xdp_action() report more info

Quoted 74 lines · Toke Høiland-Jørgensen

You still have:

Quoted 36 lines

kernel/bpf/cpumap.c +2 -2

index 585b2b77ccc4..f7359bcb8fa3 100644
@@ -195,7 +195,7 @@ static void cpu_map_bpf_prog_run_skb(struct bpf_cpu_map_entry *rcpu,
 			}
 			return;
 		default:
-			bpf_warn_invalid_xdp_action(act);
+			bpf_warn_invalid_xdp_action(skb->dev, rcpu->prog, act);
 			fallthrough;
 		case XDP_ABORTED:
 			trace_xdp_exception(skb->dev, rcpu->prog, act);

@@ -254,7 +254,7 @@ static int cpu_map_bpf_prog_run_xdp(struct bpf_cpu_map_entry *rcpu,
 			}
 			break;
 		default:
-			bpf_warn_invalid_xdp_action(act);
+			bpf_warn_invalid_xdp_action(xdpf->dev_rx, rcpu->prog, act);
 			fallthrough;
 		case XDP_DROP:
 			xdp_return_frame(xdpf);

kernel/bpf/devmap.c +1 -1

index f02d04540c0c..79bcf2169881 100644
@@ -348,7 +348,7 @@ static int dev_map_bpf_prog_run(struct bpf_prog *xdp_prog,
 				frames[nframes++] = xdpf;
 			break;
 		default:
-			bpf_warn_invalid_xdp_action(act);
+			bpf_warn_invalid_xdp_action(dev, xdp_prog, act);
 			fallthrough;
 		case XDP_ABORTED:
 			trace_xdp_exception(dev, xdp_prog, act);

kernel/bpf/devmap.c static u32 dev_map_bpf_prog_run_skb(struct sk_buff *skb, struct bpf_dtab_netdev · line 513

Quoted 8 lines

kernel/bpf/devmap.c +1 -1

@@ -507,7 +507,7 @@ static u32 dev_map_bpf_prog_run_skb(struct sk_buff *skb, struct bpf_dtab_netdev
 		__skb_push(skb, skb->mac_len);
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(act);
+		bpf_warn_invalid_xdp_action(dst->dev, dst->xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
 		trace_xdp_exception(dst->dev, dst->xdp_prog, act);

... and ...

Quoted 10 lines

net/core/filter.c +1 -1

index 3ba584bb23f8..658f7a84d9bc 100644
@@ -8179,13 +8179,13 @@ static bool xdp_is_valid_access(int off, int size,
 	return __is_valid_xdp_access(off, size);
 }
 
-void bpf_warn_invalid_xdp_action(u32 act)
+void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act)

net/core/filter.c static bool xdp_is_valid_access(int off, int size, · line 8190

Quoted 10 lines

net/core/filter.c +2 -2

 {
 	const u32 act_max = XDP_REDIRECT;
 
-	pr_warn_once("%s XDP return value %u, expect packet loss!\n",
+	pr_warn_once("%s XDP return value %u on prog %s (id %d) dev %s, expect packet loss!\n",
 		     act > act_max ? "Illegal" : "Driver unsupported",
-		     act);
+		     act, prog->aux->name, prog->aux->id, dev->name);
 }
 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);

This will still print the dev name for cpumap and devmap programs, which is misleading - it will have people looking at the drivers when the problem is somewhere else.

Quoted 2 lines

I pointed this out multiple times in comments on your last revision so I'm a bit puzzled as to why you're still doing this? :/

I'm sorry, quite a bit of relevant incoming messages keep landing in the spam folder due to corporate/gmail filters.

Quoted 2 lines

Just pass NULL as the dev from cpumap/devmap and don't print the dev name in this case...

No opposition on my side, but I think that is a bit conflicting with Alexei suggestion of keeping the message handling as simple as possible?!?

@Alexei, would something like the following:

pr_warn_once("%s XDP return value %u on prog %s (id %d) dev %s, expect packet loss!\n",
act > act_max ? "Illegal" : "Driver unsupported",

		     act, prog->aux->name, prog->aux->id, dev ? dev->name, "");

fit you?

Thanks!

Paolo