From: Alexander Sverdlin alexander.sverdlin@siemens.com

There are multiple races of zeroing dsa_ptr in struct net_device (on shutdown/remove) against asynchronous dereferences all over the net code. Widespread pattern is as follows:

CPU0 CPU1 if (netdev_uses_dsa()) dev->dsa_ptr = NULL; dev->dsa_ptr->...

One of the possible crashes:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010 CPU: 0 PID: 12 Comm: ksoftirqd/0 Tainted: G O 6.1.99+ #1 pc : lan9303_rcv lr : lan9303_rcv Call trace: lan9303_rcv dsa_switch_rcv __netif_receive_skb_list_core netif_receive_skb_list_internal napi_gro_receive fec_enet_rx_napi __napi_poll net_rx_action ...

RCU-protect dsa_ptr and use rcu_dereference() or rtnl_dereference() depending on the calling context.

Rename netdev_uses_dsa() into __netdev_uses_dsa_currently() (assumes ether RCU or RTNL lock held) and netdev_uses_dsa_currently() variants which better reflect the uselessness of the function's return value, which becomes outdated right after the call.

Fixes: ee534378f005 ("net: dsa: fix panic when DSA master device unbinds on shutdown") Cc: stable@vger.kernel.org Signed-off-by: Alexander Sverdlin alexander.sverdlin@siemens.com --- drivers/net/dsa/mt7530.c | 3 +- drivers/net/dsa/ocelot/felix.c | 3 +- drivers/net/dsa/qca/qca8k-8xxx.c | 3 +- drivers/net/ethernet/broadcom/bcmsysport.c | 8 +- drivers/net/ethernet/mediatek/airoha_eth.c | 2 +- drivers/net/ethernet/mediatek/mtk_eth_soc.c | 22 +++-- drivers/net/ethernet/mediatek/mtk_ppe.c | 15 ++- include/linux/netdevice.h | 2 +- include/net/dsa.h | 36 +++++-- include/net/dsa_stubs.h | 6 +- net/bridge/br_input.c | 2 +- net/core/dev.c | 3 +- net/core/flow_dissector.c | 19 ++-- net/dsa/conduit.c | 66 ++++++++----- net/dsa/dsa.c | 19 ++-- net/dsa/port.c | 3 +- net/dsa/tag.c | 3 +- net/dsa/tag.h | 19 ++-- net/dsa/tag_8021q.c | 10 +- net/dsa/tag_brcm.c | 2 +- net/dsa/tag_dsa.c | 8 +- net/dsa/tag_qca.c | 10 +- net/dsa/tag_sja1105.c | 22 +++-- net/dsa/user.c | 104 +++++++++++--------- net/ethernet/eth.c | 2 +- 25 files changed, 240 insertions(+), 152 deletions(-)

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c index ec18e68bf3a8..82d3f1786156 100644 --- a/drivers/net/dsa/mt7530.c +++ b/drivers/net/dsa/mt7530.c @@ -20,6 +20,7 @@ #include <linux/reset.h> #include <linux/gpio/consumer.h> #include <linux/gpio/driver.h> +#include <linux/rtnetlink.h> #include <net/dsa.h>

#include "mt7530.h" @@ -3092,7 +3093,7 @@ mt753x_conduit_state_change(struct dsa_switch *ds, const struct net_device *conduit, bool operational) { - struct dsa_port *cpu_dp = conduit->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(conduit->dsa_ptr); struct mt7530_priv *priv = ds->priv; int val = 0; u8 mask; diff --git a/drivers/net/dsa/ocelot/felix.c b/drivers/net/dsa/ocelot/felix.c index 4a705f7333f4..f6bc0ff0c116 100644 --- a/drivers/net/dsa/ocelot/felix.c +++ b/drivers/net/dsa/ocelot/felix.c @@ -21,6 +21,7 @@ #include <linux/of_net.h> #include <linux/pci.h> #include <linux/of.h> +#include <linux/rtnetlink.h> #include <net/pkt_sched.h> #include <net/dsa.h> #include "felix.h" @@ -57,7 +58,7 @@ static int felix_cpu_port_for_conduit(struct dsa_switch *ds, return lag; }

- cpu_dp = conduit->dsa_ptr; + cpu_dp = rtnl_dereference(conduit->dsa_ptr); return cpu_dp->index; }

diff --git a/drivers/net/dsa/qca/qca8k-8xxx.c b/drivers/net/dsa/qca/qca8k-8xxx.c index f8d8c70642c4..10b4d7e9be2f 100644 --- a/drivers/net/dsa/qca/qca8k-8xxx.c +++ b/drivers/net/dsa/qca/qca8k-8xxx.c @@ -20,6 +20,7 @@ #include <linux/gpio/consumer.h> #include <linux/etherdevice.h> #include <linux/dsa/tag_qca.h> +#include <linux/rtnetlink.h>

#include "qca8k.h" #include "qca8k_leds.h" @@ -1754,7 +1755,7 @@ static void qca8k_conduit_change(struct dsa_switch *ds, const struct net_device *conduit, bool operational) { - struct dsa_port *dp = conduit->dsa_ptr; + struct dsa_port *dp = rtnl_dereference(conduit->dsa_ptr); struct qca8k_priv *priv = ds->priv;

/* Ethernet MIB/MDIO is only supported for CPU port 0 */ diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c index c9faa8540859..bd9bc081346d 100644 --- a/drivers/net/ethernet/broadcom/bcmsysport.c +++ b/drivers/net/ethernet/broadcom/bcmsysport.c @@ -145,7 +145,7 @@ static void bcm_sysport_set_rx_csum(struct net_device *dev, * sure we tell the RXCHK hardware to expect a 4-bytes Broadcom * tag after the Ethernet MAC Source Address. */ - if (netdev_uses_dsa(dev)) + if (__netdev_uses_dsa_currently(dev)) reg |= RXCHK_BRCM_TAG_EN; else reg &= ~RXCHK_BRCM_TAG_EN; @@ -173,7 +173,7 @@ static void bcm_sysport_set_tx_csum(struct net_device *dev, * checksum to be computed correctly when using VLAN HW acceleration, * else it has no effect, so it can always be turned on. */ - if (netdev_uses_dsa(dev)) + if (__netdev_uses_dsa_currently(dev)) reg |= tdma_control_bit(priv, SW_BRCM_TAG); else reg &= ~tdma_control_bit(priv, SW_BRCM_TAG); @@ -1950,7 +1950,7 @@ static inline void gib_set_pad_extension(struct bcm_sysport_priv *priv)

reg = gib_readl(priv, GIB_CONTROL); /* Include Broadcom tag in pad extension and fix up IPG_LENGTH */ - if (netdev_uses_dsa(priv->netdev)) { + if (__netdev_uses_dsa_currently(priv->netdev)) { reg &= ~(GIB_PAD_EXTENSION_MASK << GIB_PAD_EXTENSION_SHIFT); reg |= ENET_BRCM_TAG_LEN << GIB_PAD_EXTENSION_SHIFT; } @@ -2299,7 +2299,7 @@ static u16 bcm_sysport_select_queue(struct net_device *dev, struct sk_buff *skb, struct bcm_sysport_tx_ring *tx_ring; unsigned int q, port;

- if (!netdev_uses_dsa(dev)) + if (!__netdev_uses_dsa_currently(dev)) return netdev_pick_tx(dev, skb, NULL);

/* DSA tagging layer will have configured the correct queue */ diff --git a/drivers/net/ethernet/mediatek/airoha_eth.c b/drivers/net/ethernet/mediatek/airoha_eth.c index 1c5b85a86df1..f7425d393b22 100644 --- a/drivers/net/ethernet/mediatek/airoha_eth.c +++ b/drivers/net/ethernet/mediatek/airoha_eth.c @@ -2255,7 +2255,7 @@ static int airoha_dev_open(struct net_device *dev) if (err) return err;

- if (netdev_uses_dsa(dev)) + if (__netdev_uses_dsa_currently(dev)) airoha_fe_set(eth, REG_GDM_INGRESS_CFG(port->id), GDM_STAG_EN_MASK); else diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c index 16ca427cf4c3..82a828349323 100644 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c @@ -24,6 +24,7 @@ #include <linux/pcs/pcs-mtk-lynxi.h> #include <linux/jhash.h> #include <linux/bitfield.h> +#include <linux/rcupdate.h> #include <net/dsa.h> #include <net/dst_metadata.h> #include <net/page_pool/helpers.h> @@ -1375,7 +1376,8 @@ static void mtk_tx_set_dma_desc_v2(struct net_device *dev, void *txd, /* tx checksum offload */ if (info->csum) data |= TX_DMA_CHKSUM_V2; - if (mtk_is_netsys_v3_or_greater(eth) && netdev_uses_dsa(dev)) + if (mtk_is_netsys_v3_or_greater(eth) && + __netdev_uses_dsa_currently(dev)) data |= TX_DMA_SPTAG_V3; } WRITE_ONCE(desc->txd5, data); @@ -2183,7 +2185,7 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget, * hardware treats the MTK special tag as a VLAN and untags it. */ if (mtk_is_netsys_v1(eth) && (trxd.rxd2 & RX_DMA_VTAG) && - netdev_uses_dsa(netdev)) { + __netdev_uses_dsa_currently(netdev)) { unsigned int port = RX_DMA_VPID(trxd.rxd3) & GENMASK(2, 0);

if (port < ARRAY_SIZE(eth->dsa_meta) && @@ -3304,7 +3306,7 @@ static void mtk_gdm_config(struct mtk_eth *eth, u32 id, u32 config)

val |= config;

- if (eth->netdev[id] && netdev_uses_dsa(eth->netdev[id])) + if (eth->netdev[id] && __netdev_uses_dsa_currently(eth->netdev[id])) val |= MTK_GDMA_SPECIAL_TAG;

mtk_w32(eth, val, MTK_GDMA_FWD_CFG(id)); @@ -3313,12 +3315,16 @@ static void mtk_gdm_config(struct mtk_eth *eth, u32 id, u32 config)

static bool mtk_uses_dsa(struct net_device *dev) { + bool ret = false; #if IS_ENABLED(CONFIG_NET_DSA) - return netdev_uses_dsa(dev) && - dev->dsa_ptr->tag_ops->proto == DSA_TAG_PROTO_MTK; -#else - return false; + struct dsa_port *dp; + + rcu_read_lock(); + dp = rcu_dereference(dev->dsa_ptr); + ret = dp && dp->tag_ops->proto == DSA_TAG_PROTO_MTK; + rcu_read_unlock(); #endif + return ret; }

static int mtk_device_event(struct notifier_block *n, unsigned long event, void *ptr) @@ -4482,7 +4488,7 @@ static u16 mtk_select_queue(struct net_device *dev, struct sk_buff *skb, struct mtk_mac *mac = netdev_priv(dev); unsigned int queue = 0;

- if (netdev_uses_dsa(dev)) + if (__netdev_uses_dsa_currently(dev)) queue = skb_get_queue_mapping(skb) + 3; else queue = mac->id; diff --git a/drivers/net/ethernet/mediatek/mtk_ppe.c b/drivers/net/ethernet/mediatek/mtk_ppe.c index 0acee405a749..0c78ec90d855 100644 --- a/drivers/net/ethernet/mediatek/mtk_ppe.c +++ b/drivers/net/ethernet/mediatek/mtk_ppe.c @@ -8,6 +8,7 @@ #include <linux/platform_device.h> #include <linux/if_ether.h> #include <linux/if_vlan.h> +#include <linux/rcupdate.h> #include <net/dst_metadata.h> #include <net/dsa.h> #include "mtk_eth_soc.h" @@ -785,9 +786,17 @@ void __mtk_ppe_check_skb(struct mtk_ppe *ppe, struct sk_buff *skb, u16 hash) switch (skb->protocol) { #if IS_ENABLED(CONFIG_NET_DSA) case htons(ETH_P_XDSA): - if (!netdev_uses_dsa(skb->dev) || - skb->dev->dsa_ptr->tag_ops->proto != DSA_TAG_PROTO_MTK) - goto out; + { + struct dsa_port *dp; + bool proto_mtk; + + rcu_read_lock(); + dp = rcu_dereference(skb->dev->dsa_ptr); + proto_mtk = dp && dp->tag_ops->proto == DSA_TAG_PROTO_MTK; + rcu_read_unlock(); + if (!proto_mtk) + goto out; + }

if (!skb_metadata_dst(skb)) tag += 4; diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 607009150b5f..e645c7eabd42 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2229,7 +2229,7 @@ struct net_device { struct vlan_info __rcu *vlan_info; #endif #if IS_ENABLED(CONFIG_NET_DSA) - struct dsa_port *dsa_ptr; + struct dsa_port __rcu *dsa_ptr; #endif #if IS_ENABLED(CONFIG_TIPC) struct tipc_bearer __rcu *tipc_ptr; diff --git a/include/net/dsa.h b/include/net/dsa.h index d7a6c2930277..ab2777611e71 100644 --- a/include/net/dsa.h +++ b/include/net/dsa.h @@ -19,6 +19,7 @@ #include <linux/phy.h> #include <linux/platform_data/dsa.h> #include <linux/phylink.h> +#include <linux/rcupdate.h> #include <net/devlink.h> #include <net/switchdev.h>

@@ -92,8 +93,9 @@ struct dsa_switch; struct dsa_device_ops { struct sk_buff *(*xmit)(struct sk_buff *skb, struct net_device *dev); struct sk_buff *(*rcv)(struct sk_buff *skb, struct net_device *dev); - void (*flow_dissect)(const struct sk_buff *skb, __be16 *proto, - int *offset); + void (*flow_dissect)(const struct sk_buff *skb, + const struct dsa_port *dp, + __be16 *proto, int *offset); int (*connect)(struct dsa_switch *ds); void (*disconnect)(struct dsa_switch *ds); unsigned int needed_headroom; @@ -1334,14 +1336,29 @@ bool dsa_mdb_present_in_other_db(struct dsa_switch *ds, int port, struct dsa_db db);

/* Keep inline for faster access in hot path */ -static inline bool netdev_uses_dsa(const struct net_device *dev) + +/* Must be called under RCU or RTNL lock */ +static inline bool __netdev_uses_dsa_currently(const struct net_device *dev) { #if IS_ENABLED(CONFIG_NET_DSA) - return dev->dsa_ptr && dev->dsa_ptr->rcv; + struct dsa_port *dp = rcu_dereference_rtnl(dev->dsa_ptr); + + return dp && dp->rcv; #endif return false; }

+static inline bool netdev_uses_dsa_currently(const struct net_device *dev) +{ + bool ret = false; +#if IS_ENABLED(CONFIG_NET_DSA) + rcu_read_lock(); + ret = __netdev_uses_dsa_currently(dev); + rcu_read_unlock(); +#endif + return ret; +} + /* All DSA tags that push the EtherType to the right (basically all except tail * tags, which don't break dissection) can be treated the same from the * perspective of the flow dissector. @@ -1355,17 +1372,20 @@ static inline bool netdev_uses_dsa(const struct net_device *dev) * that, in __be16 shorts). * * - proto: the value of the real EtherType. + * + * Must be called under RCU read lock (because of dp). */ static inline void dsa_tag_generic_flow_dissect(const struct sk_buff *skb, + const struct dsa_port *dp, __be16 *proto, int *offset) { -#if IS_ENABLED(CONFIG_NET_DSA) - const struct dsa_device_ops *ops = skb->dev->dsa_ptr->tag_ops; - int tag_len = ops->needed_headroom; + int tag_len;

+ RCU_LOCKDEP_WARN(!rcu_read_lock_any_held(), "no rcu lock held"); + + tag_len = dp->tag_ops->needed_headroom; *offset = tag_len; *proto = ((__be16 *)skb->data)[(tag_len / 2) - 1]; -#endif }

void dsa_unregister_switch(struct dsa_switch *ds); diff --git a/include/net/dsa_stubs.h b/include/net/dsa_stubs.h index 6f384897f287..ca899305ba36 100644 --- a/include/net/dsa_stubs.h +++ b/include/net/dsa_stubs.h @@ -22,9 +22,6 @@ static inline int dsa_conduit_hwtstamp_validate(struct net_device *dev, const struct kernel_hwtstamp_config *config, struct netlink_ext_ack *extack) { - if (!netdev_uses_dsa(dev)) - return 0; - /* rtnl_lock() is a sufficient guarantee, because as long as * netdev_uses_dsa() returns true, the dsa_core module is still * registered, and so, dsa_unregister_stubs() couldn't have run. @@ -33,6 +30,9 @@ static inline int dsa_conduit_hwtstamp_validate(struct net_device *dev, */ ASSERT_RTNL();

+ if (!__netdev_uses_dsa_currently(dev)) + return 0; + return dsa_stubs->conduit_hwtstamp_validate(dev, config, extack); }

diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c index ceaa5a89b947..542cfc5678df 100644 --- a/net/bridge/br_input.c +++ b/net/bridge/br_input.c @@ -443,7 +443,7 @@ static rx_handler_result_t br_handle_frame_dummy(struct sk_buff **pskb)

rx_handler_func_t *br_get_rx_handler(const struct net_device *dev) { - if (netdev_uses_dsa(dev)) + if (__netdev_uses_dsa_currently(dev)) return br_handle_frame_dummy;

return br_handle_frame; diff --git a/net/core/dev.c b/net/core/dev.c index f66e61407883..9ae1c097cbad 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -5568,7 +5568,8 @@ static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, } }

- if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(skb->dev)) { + if (unlikely(skb_vlan_tag_present(skb)) && + !__netdev_uses_dsa_currently(skb->dev)) { check_vlan_id: if (skb_vlan_tag_get_id(skb)) { /* Vlan id is non 0 and vlan_do_receive() above couldn't diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 0e638a37aa09..e1523c609bb7 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -1071,25 +1071,30 @@ bool __skb_flow_dissect(const struct net *net, nhoff = skb_network_offset(skb); hlen = skb_headlen(skb); #if IS_ENABLED(CONFIG_NET_DSA) - if (unlikely(skb->dev && netdev_uses_dsa(skb->dev) && - proto == htons(ETH_P_XDSA))) { + if (unlikely(skb->dev && proto == htons(ETH_P_XDSA))) { struct metadata_dst *md_dst = skb_metadata_dst(skb); - const struct dsa_device_ops *ops; + struct dsa_port *dp; int offset = 0;

- ops = skb->dev->dsa_ptr->tag_ops; + rcu_read_lock(); + + dp = rcu_dereference(skb->dev->dsa_ptr); /* Only DSA header taggers break flow dissection */ - if (ops->needed_headroom && + if (dp && dp->tag_ops->needed_headroom && (!md_dst || md_dst->type != METADATA_HW_PORT_MUX)) { - if (ops->flow_dissect) - ops->flow_dissect(skb, &proto, &offset); + if (dp->tag_ops->flow_dissect) + dp->tag_ops->flow_dissect(skb, dp, + &proto, &offset); else dsa_tag_generic_flow_dissect(skb, + dp, &proto, &offset); hlen -= offset; nhoff += offset; } + + rcu_read_unlock(); } #endif } diff --git a/net/dsa/conduit.c b/net/dsa/conduit.c index 3dfdb3cb47dc..967770cdf88f 100644 --- a/net/dsa/conduit.c +++ b/net/dsa/conduit.c @@ -9,6 +9,7 @@ #include <linux/ethtool.h> #include <linux/netdevice.h> #include <linux/netlink.h> +#include <linux/rcupdate.h> #include <net/dsa.h>

#include "conduit.h" @@ -18,7 +19,7 @@

static int dsa_conduit_get_regs_len(struct net_device *dev) { - struct dsa_port *cpu_dp = dev->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr); const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops; struct dsa_switch *ds = cpu_dp->ds; int port = cpu_dp->index; @@ -48,7 +49,7 @@ static int dsa_conduit_get_regs_len(struct net_device *dev) static void dsa_conduit_get_regs(struct net_device *dev, struct ethtool_regs *regs, void *data) { - struct dsa_port *cpu_dp = dev->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr); const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops; struct dsa_switch *ds = cpu_dp->ds; struct ethtool_drvinfo *cpu_info; @@ -84,7 +85,7 @@ static void dsa_conduit_get_ethtool_stats(struct net_device *dev, struct ethtool_stats *stats, uint64_t *data) { - struct dsa_port *cpu_dp = dev->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr); const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops; struct dsa_switch *ds = cpu_dp->ds; int port = cpu_dp->index; @@ -103,7 +104,7 @@ static void dsa_conduit_get_ethtool_phy_stats(struct net_device *dev, struct ethtool_stats *stats, uint64_t *data) { - struct dsa_port *cpu_dp = dev->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr); const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops; struct dsa_switch *ds = cpu_dp->ds; int port = cpu_dp->index; @@ -127,7 +128,7 @@ static void dsa_conduit_get_ethtool_phy_stats(struct net_device *dev,

static int dsa_conduit_get_sset_count(struct net_device *dev, int sset) { - struct dsa_port *cpu_dp = dev->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr); const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops; struct dsa_switch *ds = cpu_dp->ds; int count = 0; @@ -150,7 +151,7 @@ static int dsa_conduit_get_sset_count(struct net_device *dev, int sset) static void dsa_conduit_get_strings(struct net_device *dev, uint32_t stringset, uint8_t *data) { - struct dsa_port *cpu_dp = dev->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr); const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops; struct dsa_switch *ds = cpu_dp->ds; int port = cpu_dp->index; @@ -202,7 +203,7 @@ int __dsa_conduit_hwtstamp_validate(struct net_device *dev, const struct kernel_hwtstamp_config *config, struct netlink_ext_ack *extack) { - struct dsa_port *cpu_dp = dev->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr); struct dsa_switch *ds = cpu_dp->ds; struct dsa_switch_tree *dst; struct dsa_port *dp; @@ -222,7 +223,7 @@ int __dsa_conduit_hwtstamp_validate(struct net_device *dev,

static int dsa_conduit_ethtool_setup(struct net_device *dev) { - struct dsa_port *cpu_dp = dev->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr); struct dsa_switch *ds = cpu_dp->ds; struct ethtool_ops *ops;

@@ -251,7 +252,7 @@ static int dsa_conduit_ethtool_setup(struct net_device *dev)

static void dsa_conduit_ethtool_teardown(struct net_device *dev) { - struct dsa_port *cpu_dp = dev->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr);

if (netif_is_lag_master(dev)) return; @@ -267,13 +268,14 @@ static void dsa_conduit_ethtool_teardown(struct net_device *dev) */ static void dsa_conduit_set_promiscuity(struct net_device *dev, int inc) { - const struct dsa_device_ops *ops = dev->dsa_ptr->tag_ops; + const struct dsa_device_ops *ops; + + ASSERT_RTNL(); + ops = rtnl_dereference(dev->dsa_ptr)->tag_ops;

if ((dev->priv_flags & IFF_UNICAST_FLT) && !ops->promisc_on_conduit) return;

- ASSERT_RTNL(); - dev_set_promiscuity(dev, inc); }

@@ -281,10 +283,17 @@ static ssize_t tagging_show(struct device *d, struct device_attribute *attr, char *buf) { struct net_device *dev = to_net_dev(d); - struct dsa_port *cpu_dp = dev->dsa_ptr; + struct dsa_port *cpu_dp; + int ret = 0; + + rcu_read_lock(); + cpu_dp = rcu_dereference(dev->dsa_ptr); + if (cpu_dp) + ret = sysfs_emit(buf, "%s\n", + dsa_tag_protocol_to_str(cpu_dp->tag_ops)); + rcu_read_unlock();

- return sysfs_emit(buf, "%s\n", - dsa_tag_protocol_to_str(cpu_dp->tag_ops)); + return ret; }

static ssize_t tagging_store(struct device *d, struct device_attribute *attr, @@ -293,7 +302,7 @@ static ssize_t tagging_store(struct device *d, struct device_attribute *attr, const struct dsa_device_ops *new_tag_ops, *old_tag_ops; const char *end = strchrnul(buf, '\n'), *name; struct net_device *dev = to_net_dev(d); - struct dsa_port *cpu_dp = dev->dsa_ptr; + struct dsa_port *cpu_dp; size_t len = end - buf; int err;

@@ -305,13 +314,17 @@ static ssize_t tagging_store(struct device *d, struct device_attribute *attr, if (!name) return -ENOMEM;

- old_tag_ops = cpu_dp->tag_ops; new_tag_ops = dsa_tag_driver_get_by_name(name); kfree(name); /* Bad tagger name? */ if (IS_ERR(new_tag_ops)) return PTR_ERR(new_tag_ops);

+ if (!rtnl_trylock()) + return restart_syscall(); + + cpu_dp = rtnl_dereference(dev->dsa_ptr); + old_tag_ops = cpu_dp->tag_ops; if (new_tag_ops == old_tag_ops) /* Drop the temporarily held duplicate reference, since * the DSA switch tree uses this tagger. @@ -321,6 +334,7 @@ static ssize_t tagging_store(struct device *d, struct device_attribute *attr, err = dsa_tree_change_tag_proto(cpu_dp->ds->dst, new_tag_ops, old_tag_ops); if (err) { + rtnl_unlock(); /* On failure the old tagger is restored, so we don't need the * driver for the new one. */ @@ -331,6 +345,7 @@ static ssize_t tagging_store(struct device *d, struct device_attribute *attr, /* On success we no longer need the module for the old tagging protocol */ out: + rtnl_unlock(); dsa_tag_driver_put(old_tag_ops); return count; } @@ -384,13 +399,11 @@ int dsa_conduit_setup(struct net_device *dev, struct dsa_port *cpu_dp) netdev_warn(dev, "error %d setting MTU to %d to include DSA overhead\n", ret, mtu);

- /* If we use a tagging format that doesn't have an ethertype - * field, make sure that all packets from this point on get - * sent to the tag format's receive function. + rcu_assign_pointer(dev->dsa_ptr, cpu_dp); + /* + * No need to synchronize_rcu() here because dsa_ptr in not going away + * before it will be zeroed */ - wmb(); - - dev->dsa_ptr = cpu_dp;

dsa_conduit_set_promiscuity(dev, 1);

@@ -418,13 +431,12 @@ void dsa_conduit_teardown(struct net_device *dev) dsa_conduit_reset_mtu(dev); dsa_conduit_set_promiscuity(dev, -1);

- dev->dsa_ptr = NULL; - /* If we used a tagging format that doesn't have an ethertype * field, make sure that all packets from this point get sent * without the tag and go through the regular receive path. */ - wmb(); + rcu_assign_pointer(dev->dsa_ptr, NULL); + synchronize_rcu(); }

int dsa_conduit_lag_setup(struct net_device *lag_dev, struct dsa_port *cpu_dp, @@ -434,7 +446,7 @@ int dsa_conduit_lag_setup(struct net_device *lag_dev, struct dsa_port *cpu_dp, bool conduit_setup = false; int err;

- if (!netdev_uses_dsa(lag_dev)) { + if (!__netdev_uses_dsa_currently(lag_dev)) { err = dsa_conduit_setup(lag_dev, cpu_dp); if (err) return err; diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c index 668c729946ea..36b9ebddc8b8 100644 --- a/net/dsa/dsa.c +++ b/net/dsa/dsa.c @@ -976,6 +976,8 @@ static int dsa_tree_bind_tag_proto(struct dsa_switch_tree *dst, /* Since the dsa/tagging sysfs device attribute is per conduit, the assumption * is that all DSA switches within a tree share the same tagger, otherwise * they would have formed disjoint trees (different "dsa,member" values). + * + * Must be called with RTNL lock held. */ int dsa_tree_change_tag_proto(struct dsa_switch_tree *dst, const struct dsa_device_ops *tag_ops, @@ -985,8 +987,7 @@ int dsa_tree_change_tag_proto(struct dsa_switch_tree *dst, struct dsa_port *dp; int err = -EBUSY;

- if (!rtnl_trylock()) - return restart_syscall(); + ASSERT_RTNL();

/* At the moment we don't allow changing the tag protocol under * traffic. The rtnl_mutex also happens to serialize concurrent @@ -1011,15 +1012,12 @@ int dsa_tree_change_tag_proto(struct dsa_switch_tree *dst, if (err) goto out_unwind_tagger;

- rtnl_unlock(); - return 0;

out_unwind_tagger: info.tag_ops = old_tag_ops; dsa_tree_notify(dst, DSA_NOTIFIER_TAG_PROTO, &info); out_unlock: - rtnl_unlock(); return err; }

@@ -1027,7 +1025,7 @@ static void dsa_tree_conduit_state_change(struct dsa_switch_tree *dst, struct net_device *conduit) { struct dsa_notifier_conduit_state_info info; - struct dsa_port *cpu_dp = conduit->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(conduit->dsa_ptr);

info.conduit = conduit; info.operational = dsa_port_conduit_is_operational(cpu_dp); @@ -1039,7 +1037,7 @@ void dsa_tree_conduit_admin_state_change(struct dsa_switch_tree *dst, struct net_device *conduit, bool up) { - struct dsa_port *cpu_dp = conduit->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(conduit->dsa_ptr); bool notify = false;

/* Don't keep track of admin state on LAG DSA conduits, @@ -1062,7 +1060,7 @@ void dsa_tree_conduit_oper_state_change(struct dsa_switch_tree *dst, struct net_device *conduit, bool up) { - struct dsa_port *cpu_dp = conduit->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(conduit->dsa_ptr); bool notify = false;

/* Don't keep track of oper state on LAG DSA conduits, @@ -1594,10 +1592,11 @@ void dsa_switch_shutdown(struct dsa_switch *ds) }

/* Disconnect from further netdevice notifiers on the conduit, - * since netdev_uses_dsa() will now return false. + * from now on, netdev_uses_dsa_currently() will return false. */ dsa_switch_for_each_cpu_port(dp, ds) - dp->conduit->dsa_ptr = NULL; + rcu_assign_pointer(dp->conduit->dsa_ptr, NULL); + synchronize_rcu();

rtnl_unlock(); out: diff --git a/net/dsa/port.c b/net/dsa/port.c index 25258b33e59e..6220c520d776 100644 --- a/net/dsa/port.c +++ b/net/dsa/port.c @@ -11,6 +11,7 @@ #include <linux/notifier.h> #include <linux/of_mdio.h> #include <linux/of_net.h> +#include <linux/rtnetlink.h>

#include "dsa.h" #include "port.h" @@ -1414,7 +1415,7 @@ static int dsa_port_assign_conduit(struct dsa_port *dp, if (err && fail_on_err) return err;

- dp->cpu_dp = conduit->dsa_ptr; + dp->cpu_dp = rtnl_dereference(conduit->dsa_ptr); dp->cpu_port_in_lag = netif_is_lag_master(conduit);

return 0; diff --git a/net/dsa/tag.c b/net/dsa/tag.c index 79ad105902d9..ba662adecc14 100644 --- a/net/dsa/tag.c +++ b/net/dsa/tag.c @@ -10,6 +10,7 @@ #include <linux/netdevice.h> #include <linux/ptp_classify.h> #include <linux/skbuff.h> +#include <linux/rcupdate.h> #include <net/dsa.h> #include <net/dst_metadata.h>

@@ -55,7 +56,7 @@ static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *unused) { struct metadata_dst *md_dst = skb_metadata_dst(skb); - struct dsa_port *cpu_dp = dev->dsa_ptr; + struct dsa_port *cpu_dp = rcu_dereference(dev->dsa_ptr); struct sk_buff *nskb = NULL; struct dsa_user_priv *p;

diff --git a/net/dsa/tag.h b/net/dsa/tag.h index d5707870906b..dbb2217d4344 100644 --- a/net/dsa/tag.h +++ b/net/dsa/tag.h @@ -5,6 +5,7 @@

#include <linux/if_vlan.h> #include <linux/list.h> +#include <linux/rcupdate.h> #include <linux/types.h> #include <net/dsa.h>

@@ -32,11 +33,14 @@ static inline int dsa_tag_protocol_overhead(const struct dsa_device_ops *ops) static inline struct net_device *dsa_conduit_find_user(struct net_device *dev, int device, int port) { - struct dsa_port *cpu_dp = dev->dsa_ptr; - struct dsa_switch_tree *dst = cpu_dp->dst; + struct dsa_port *cpu_dp; struct dsa_port *dp;

- list_for_each_entry(dp, &dst->ports, list) + cpu_dp = rcu_dereference(dev->dsa_ptr); + if (!cpu_dp) + return NULL; + + list_for_each_entry(dp, &cpu_dp->dst->ports, list) if (dp->ds->index == device && dp->index == port && dp->type == DSA_PORT_TYPE_USER) return dp->user; @@ -184,14 +188,17 @@ static inline struct sk_buff *dsa_software_vlan_untag(struct sk_buff *skb) static inline struct net_device * dsa_find_designated_bridge_port_by_vid(struct net_device *conduit, u16 vid) { - struct dsa_port *cpu_dp = conduit->dsa_ptr; - struct dsa_switch_tree *dst = cpu_dp->dst; + struct dsa_port *cpu_dp; struct bridge_vlan_info vinfo; struct net_device *user; struct dsa_port *dp; int err;

- list_for_each_entry(dp, &dst->ports, list) { + cpu_dp = rcu_dereference(conduit->dsa_ptr); + if (!cpu_dp) + return NULL; + + list_for_each_entry(dp, &cpu_dp->dst->ports, list) { if (dp->type != DSA_PORT_TYPE_USER) continue;

diff --git a/net/dsa/tag_8021q.c b/net/dsa/tag_8021q.c index 3ee53e28ec2e..c9fb4fd2a4cf 100644 --- a/net/dsa/tag_8021q.c +++ b/net/dsa/tag_8021q.c @@ -5,6 +5,7 @@ * primitives for taggers that rely on 802.1Q VLAN tags to use. */ #include <linux/if_vlan.h> +#include <linux/rcupdate.h> #include <linux/dsa/8021q.h>

#include "port.h" @@ -474,14 +475,17 @@ EXPORT_SYMBOL_GPL(dsa_8021q_xmit); static struct net_device * dsa_tag_8021q_find_port_by_vbid(struct net_device *conduit, int vbid) { - struct dsa_port *cpu_dp = conduit->dsa_ptr; - struct dsa_switch_tree *dst = cpu_dp->dst; + struct dsa_port *cpu_dp; struct dsa_port *dp;

if (WARN_ON(!vbid)) return NULL;

- dsa_tree_for_each_user_port(dp, dst) { + cpu_dp = rcu_dereference(conduit->dsa_ptr); + if (!cpu_dp) + return NULL; + + dsa_tree_for_each_user_port(dp, cpu_dp->dst) { if (!dp->bridge) continue;

diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c index 8c3c068728e5..c87f16cd959f 100644 --- a/net/dsa/tag_brcm.c +++ b/net/dsa/tag_brcm.c @@ -269,7 +269,7 @@ static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb, return NULL;

/* VLAN tag is added by BCM63xx internal switch */ - if (netdev_uses_dsa(skb->dev)) + if (__netdev_uses_dsa_currently(skb->dev)) len += VLAN_HLEN;

/* Remove Broadcom tag and update checksum */ diff --git a/net/dsa/tag_dsa.c b/net/dsa/tag_dsa.c index 2a2c4fb61a65..7f5dc8d384c9 100644 --- a/net/dsa/tag_dsa.c +++ b/net/dsa/tag_dsa.c @@ -48,6 +48,7 @@ #include <linux/dsa/mv88e6xxx.h> #include <linux/etherdevice.h> #include <linux/list.h> +#include <linux/rcupdate.h> #include <linux/slab.h>

#include "tag.h" @@ -257,14 +258,15 @@ static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev, source_port = (dsa_header[1] >> 3) & 0x1f;

if (trunk) { - struct dsa_port *cpu_dp = dev->dsa_ptr; - struct dsa_lag *lag; + struct dsa_port *cpu_dp = rcu_dereference(dev->dsa_ptr); + struct dsa_lag *lag = NULL;

/* The exact source port is not available in the tag, * so we inject the frame directly on the upper * team/bond. */ - lag = dsa_lag_by_id(cpu_dp->dst, source_port + 1); + if (cpu_dp) + lag = dsa_lag_by_id(cpu_dp->dst, source_port + 1); skb->dev = lag ? lag->dev : NULL; } else { skb->dev = dsa_conduit_find_user(dev, source_device, diff --git a/net/dsa/tag_qca.c b/net/dsa/tag_qca.c index 0cf61286b426..dbc1f659ed07 100644 --- a/net/dsa/tag_qca.c +++ b/net/dsa/tag_qca.c @@ -5,6 +5,7 @@

#include <linux/etherdevice.h> #include <linux/bitfield.h> +#include <linux/rcupdate.h> #include <net/dsa.h> #include <linux/dsa/tag_qca.h>

@@ -36,8 +37,8 @@ static struct sk_buff *qca_tag_xmit(struct sk_buff *skb, struct net_device *dev) static struct sk_buff *qca_tag_rcv(struct sk_buff *skb, struct net_device *dev) { struct qca_tagger_data *tagger_data; - struct dsa_port *dp = dev->dsa_ptr; - struct dsa_switch *ds = dp->ds; + struct dsa_port *dp; + struct dsa_switch *ds; u8 ver, pk_type; __be16 *phdr; int port; @@ -45,6 +46,11 @@ static struct sk_buff *qca_tag_rcv(struct sk_buff *skb, struct net_device *dev)

BUILD_BUG_ON(sizeof(struct qca_mgmt_ethhdr) != QCA_HDR_MGMT_HEADER_LEN + QCA_HDR_LEN);

+ dp = rcu_dereference(dev->dsa_ptr); + if (!dp) + return NULL; + ds = dp->ds; + tagger_data = ds->tagger_data;

if (unlikely(!pskb_may_pull(skb, QCA_HDR_LEN))) diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c index 3e902af7eea6..0746a7d34178 100644 --- a/net/dsa/tag_sja1105.c +++ b/net/dsa/tag_sja1105.c @@ -5,6 +5,7 @@ #include <linux/dsa/sja1105.h> #include <linux/dsa/8021q.h> #include <linux/packing.h> +#include <linux/rcupdate.h>

#include "tag.h" #include "tag_8021q.h" @@ -530,12 +531,13 @@ static struct sk_buff *sja1110_rcv_meta(struct sk_buff *skb, u16 rx_header) int n_ts = SJA1110_RX_HEADER_N_TS(rx_header); struct sja1105_tagger_data *tagger_data; struct net_device *conduit = skb->dev; + struct dsa_switch *ds = NULL; struct dsa_port *cpu_dp; - struct dsa_switch *ds; int i;

- cpu_dp = conduit->dsa_ptr; - ds = dsa_switch_find(cpu_dp->dst->index, switch_id); + cpu_dp = rcu_dereference(conduit->dsa_ptr); + if (cpu_dp) + ds = dsa_switch_find(cpu_dp->dst->index, switch_id); if (!ds) { net_err_ratelimited("%s: cannot find switch id %d\n", conduit->name, switch_id); @@ -662,24 +664,26 @@ static struct sk_buff *sja1110_rcv(struct sk_buff *skb, return skb; }

-static void sja1105_flow_dissect(const struct sk_buff *skb, __be16 *proto, - int *offset) +static void sja1105_flow_dissect(const struct sk_buff *skb, + const struct dsa_port *dp, + __be16 *proto, int *offset) { /* No tag added for management frames, all ok */ if (unlikely(sja1105_is_link_local(skb))) return;

- dsa_tag_generic_flow_dissect(skb, proto, offset); + dsa_tag_generic_flow_dissect(skb, dp, proto, offset); }

-static void sja1110_flow_dissect(const struct sk_buff *skb, __be16 *proto, - int *offset) +static void sja1110_flow_dissect(const struct sk_buff *skb, + const struct dsa_port *dp, + __be16 *proto, int *offset) { /* Management frames have 2 DSA tags on RX, so the needed_headroom we * declared is fine for the generic dissector adjustment procedure. */ if (unlikely(sja1105_is_link_local(skb))) - return dsa_tag_generic_flow_dissect(skb, proto, offset); + return dsa_tag_generic_flow_dissect(skb, dp, proto, offset);

/* For the rest, there is a single DSA tag, the tag_8021q one */ *offset = VLAN_HLEN; diff --git a/net/dsa/user.c b/net/dsa/user.c index f5adfa1d978a..2afd21e34772 100644 --- a/net/dsa/user.c +++ b/net/dsa/user.c @@ -21,6 +21,7 @@ #include <linux/if_hsr.h> #include <net/dcbnl.h> #include <linux/netpoll.h> +#include <linux/rcupdate.h> #include <linux/string.h>

#include "conduit.h" @@ -2839,7 +2840,7 @@ int dsa_user_change_conduit(struct net_device *dev, struct net_device *conduit, return -EOPNOTSUPP; }

- if (!netdev_uses_dsa(conduit)) { + if (!__netdev_uses_dsa_currently(conduit)) { NL_SET_ERR_MSG_MOD(extack, "Interface not eligible as DSA conduit"); return -EOPNOTSUPP; @@ -3141,8 +3142,8 @@ static int dsa_lag_conduit_validate(struct net_device *lag_dev,

netdev_for_each_lower_dev(lag_dev, lower1, iter1) { netdev_for_each_lower_dev(lag_dev, lower2, iter2) { - if (!netdev_uses_dsa(lower1) || - !netdev_uses_dsa(lower2)) { + if (!__netdev_uses_dsa_currently(lower1) || + !__netdev_uses_dsa_currently(lower2)) { NL_SET_ERR_MSG_MOD(extack, "All LAG ports must be eligible as DSA conduits"); return notifier_from_errno(-EINVAL); @@ -3151,8 +3152,8 @@ static int dsa_lag_conduit_validate(struct net_device *lag_dev, if (lower1 == lower2) continue;

- if (!dsa_port_tree_same(lower1->dsa_ptr, - lower2->dsa_ptr)) { + if (!dsa_port_tree_same(rtnl_dereference(lower1->dsa_ptr), + rtnl_dereference(lower2->dsa_ptr))) { NL_SET_ERR_MSG_MOD(extack, "LAG contains DSA conduits of disjoint switch trees"); return notifier_from_errno(-EINVAL); @@ -3169,7 +3170,7 @@ dsa_conduit_prechangeupper_sanity_check(struct net_device *conduit, { struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(&info->info);

- if (!netdev_uses_dsa(conduit)) + if (!__netdev_uses_dsa_currently(conduit)) return NOTIFY_DONE;

if (!info->linking) @@ -3205,20 +3206,22 @@ dsa_lag_conduit_prechangelower_sanity_check(struct net_device *dev, struct net_device *lower; struct list_head *iter;

- if (!netdev_uses_dsa(lag_dev) || !netif_is_lag_master(lag_dev)) + if (!__netdev_uses_dsa_currently(lag_dev) || + !netif_is_lag_master(lag_dev)) return NOTIFY_DONE;

if (!info->linking) return NOTIFY_DONE;

- if (!netdev_uses_dsa(dev)) { + if (!__netdev_uses_dsa_currently(dev)) { NL_SET_ERR_MSG(extack, "Only DSA conduits can join a LAG DSA conduit"); return notifier_from_errno(-EINVAL); }

netdev_for_each_lower_dev(lag_dev, lower, iter) { - if (!dsa_port_tree_same(dev->dsa_ptr, lower->dsa_ptr)) { + if (!dsa_port_tree_same(rtnl_dereference(dev->dsa_ptr), + rtnl_dereference(lower->dsa_ptr))) { NL_SET_ERR_MSG(extack, "Interface is DSA conduit for a different switch tree than this LAG"); return notifier_from_errno(-EINVAL); @@ -3257,7 +3260,8 @@ dsa_bridge_prechangelower_sanity_check(struct net_device *new_lower, extack = netdev_notifier_info_to_extack(&info->info);

netdev_for_each_lower_dev(br, lower, iter) { - if (!netdev_uses_dsa(new_lower) && !netdev_uses_dsa(lower)) + if (!__netdev_uses_dsa_currently(new_lower) && + !__netdev_uses_dsa_currently(lower)) continue;

if (!netdev_port_same_parent_id(lower, new_lower)) { @@ -3295,7 +3299,7 @@ static int dsa_conduit_lag_join(struct net_device *conduit, struct netdev_lag_upper_info *uinfo, struct netlink_ext_ack *extack) { - struct dsa_port *cpu_dp = conduit->dsa_ptr; + struct dsa_port *cpu_dp = rtnl_dereference(conduit->dsa_ptr); struct dsa_switch_tree *dst = cpu_dp->dst; struct dsa_port *dp; int err; @@ -3328,7 +3332,7 @@ static int dsa_conduit_lag_join(struct net_device *conduit, } }

- dsa_conduit_lag_teardown(lag_dev, conduit->dsa_ptr); + dsa_conduit_lag_teardown(lag_dev, rtnl_dereference(conduit->dsa_ptr));

return err; } @@ -3336,17 +3340,16 @@ static int dsa_conduit_lag_join(struct net_device *conduit, static void dsa_conduit_lag_leave(struct net_device *conduit, struct net_device *lag_dev) { - struct dsa_port *dp, *cpu_dp = lag_dev->dsa_ptr; + struct dsa_port *dp, *cpu_dp = rtnl_dereference(lag_dev->dsa_ptr); struct dsa_switch_tree *dst = cpu_dp->dst; struct dsa_port *new_cpu_dp = NULL; struct net_device *lower; struct list_head *iter;

netdev_for_each_lower_dev(lag_dev, lower, iter) { - if (netdev_uses_dsa(lower)) { - new_cpu_dp = lower->dsa_ptr; + new_cpu_dp = rtnl_dereference(lower->dsa_ptr); + if (new_cpu_dp) break; - } }

if (new_cpu_dp) { @@ -3360,8 +3363,11 @@ static void dsa_conduit_lag_leave(struct net_device *conduit, /* Update the index of the virtual CPU port to match the lowest * physical CPU port */ - lag_dev->dsa_ptr = new_cpu_dp; - wmb(); + rcu_assign_pointer(lag_dev->dsa_ptr, new_cpu_dp); + /* + * No need to synchronize_rcu() here because dsa_ptr in not + * going away before it will be zeroed + */ } else { /* If the LAG DSA conduit has no ports left, migrate back all * user ports to the first physical CPU port @@ -3372,7 +3378,7 @@ static void dsa_conduit_lag_leave(struct net_device *conduit, /* This DSA conduit has left its LAG in any case, so let * the CPU port leave the hardware LAG as well */ - dsa_conduit_lag_teardown(lag_dev, conduit->dsa_ptr); + dsa_conduit_lag_teardown(lag_dev, rtnl_dereference(conduit->dsa_ptr)); }

static int dsa_conduit_changeupper(struct net_device *dev, @@ -3381,7 +3387,7 @@ static int dsa_conduit_changeupper(struct net_device *dev, struct netlink_ext_ack *extack; int err = NOTIFY_DONE;

- if (!netdev_uses_dsa(dev)) + if (!__netdev_uses_dsa_currently(dev)) return err;

extack = netdev_notifier_info_to_extack(&info->info); @@ -3464,14 +3470,14 @@ static int dsa_user_netdevice_event(struct notifier_block *nb, err = dsa_port_lag_change(dp, info->lower_state_info); }

+ dp = rtnl_dereference(dev->dsa_ptr); + if (!dp) + return NOTIFY_OK; + /* Mirror LAG port events on DSA conduits that are in * a LAG towards their respective switch CPU ports */ - if (netdev_uses_dsa(dev)) { - dp = dev->dsa_ptr; - - err = dsa_port_lag_change(dp, info->lower_state_info); - } + err = dsa_port_lag_change(dp, info->lower_state_info);

return notifier_from_errno(err); } @@ -3481,39 +3487,41 @@ static int dsa_user_netdevice_event(struct notifier_block *nb, * DSA driver may require the conduit port (and indirectly * the tagger) to be available for some special operation. */ - if (netdev_uses_dsa(dev)) { - struct dsa_port *cpu_dp = dev->dsa_ptr; - struct dsa_switch_tree *dst = cpu_dp->ds->dst; - - /* Track when the conduit port is UP */ - dsa_tree_conduit_oper_state_change(dst, dev, - netif_oper_up(dev)); - - /* Track when the conduit port is ready and can accept - * packet. - * NETDEV_UP event is not enough to flag a port as ready. - * We also have to wait for linkwatch_do_dev to dev_activate - * and emit a NETDEV_CHANGE event. - * We check if a conduit port is ready by checking if the dev - * have a qdisc assigned and is not noop. - */ - dsa_tree_conduit_admin_state_change(dst, dev, - !qdisc_tx_is_noop(dev)); + struct dsa_port *cpu_dp = rtnl_dereference(dev->dsa_ptr); + struct dsa_switch_tree *dst;

- return NOTIFY_OK; - } + if (!cpu_dp) + return NOTIFY_DONE; + + dst = cpu_dp->ds->dst; + + /* Track when the conduit port is UP */ + dsa_tree_conduit_oper_state_change(dst, dev, + netif_oper_up(dev)); + + /* Track when the conduit port is ready and can accept + * packet. + * NETDEV_UP event is not enough to flag a port as ready. + * We also have to wait for linkwatch_do_dev to dev_activate + * and emit a NETDEV_CHANGE event. + * We check if a conduit port is ready by checking if the dev + * have a qdisc assigned and is not noop. + */ + dsa_tree_conduit_admin_state_change(dst, dev, + !qdisc_tx_is_noop(dev)); + + return NOTIFY_OK;

- return NOTIFY_DONE; } case NETDEV_GOING_DOWN: { struct dsa_port *dp, *cpu_dp; struct dsa_switch_tree *dst; LIST_HEAD(close_list);

- if (!netdev_uses_dsa(dev)) + cpu_dp = rtnl_dereference(dev->dsa_ptr); + if (!cpu_dp) return NOTIFY_DONE;

- cpu_dp = dev->dsa_ptr; dst = cpu_dp->ds->dst;

dsa_tree_conduit_admin_state_change(dst, dev, false); diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c index 4e3651101b86..a05ff82551c3 100644 --- a/net/ethernet/eth.c +++ b/net/ethernet/eth.c @@ -170,7 +170,7 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev) * variants has been configured on the receiving interface, * and if so, set skb->protocol without looking at the packet. */ - if (unlikely(netdev_uses_dsa(dev))) + if (unlikely(netdev_uses_dsa_currently(dev))) return htons(ETH_P_XDSA);

if (likely(eth_proto_is_802_3(eth->h_proto)))