From: Vladimir Oltean <vladimir.olt...@nxp.com>

dev_get_stats can now return error codes. Convert all remaining call
sites to look at that error code and stop processing.

The effects of simulating a kernel error (returning -ENOMEM) upon
existing programs or kernel interfaces:

- ifconfig and "cat /proc/net/dev" print up until the interface that
  failed, and there they return:
cat: read error: Cannot allocate memory

- ifstat and "ip -s -s link show":
RTNETLINK answers: Cannot allocate memory
Dump terminated

Some call sites are coming from a context that returns void (ethtool
stats, workqueue context). So since we can't report to the upper layer,
do the next best thing: print an error to the console.

This patch wraps up the conversion of existing dev_get_stats callers, so
we can add the __must_check attribute now to ensure that future callers
keep doing this too.

Signed-off-by: Vladimir Oltean <vladimir.olt...@nxp.com>
---
Changes in v6:
- Fixed rtnetlink incorrectly returning 0 in rtnl_fill_ifinfo on
  nla_put_failure and causing "ip a" to not show any interfaces.
- Squashed the patch to propagate errors with the one to terminate them.

Changes in v5:
- Actually propagate errors from bonding and net_failover from within
  this patch.
- Properly propagating the dev_get_stats() error code from
  rtnl_fill_stats now, and not -EMSGSIZE.

Changes in v4:
Patch is new (Eric's suggestion).

 arch/s390/appldata/appldata_net_sum.c         | 10 ++++--
 drivers/leds/trigger/ledtrig-netdev.c         |  9 ++++-
 drivers/net/bonding/bond_main.c               | 29 ++++++++++++----
 .../ethernet/apm/xgene/xgene_enet_ethtool.c   |  9 +++--
 .../net/ethernet/hisilicon/hns/hns_ethtool.c  |  7 +++-
 drivers/net/ethernet/intel/e1000e/ethtool.c   |  9 +++--
 .../net/ethernet/intel/ixgbe/ixgbe_ethtool.c  |  9 +++--
 drivers/net/ethernet/intel/ixgbevf/ethtool.c  |  9 +++--
 drivers/net/net_failover.c                    | 33 ++++++++++++++-----
 drivers/parisc/led.c                          |  7 +++-
 drivers/usb/gadget/function/rndis.c           |  4 ++-
 include/linux/netdevice.h                     |  3 +-
 net/8021q/vlanproc.c                          |  7 ++--
 net/core/dev.c                                |  3 +-
 net/core/net-procfs.c                         | 16 ++++++---
 net/core/net-sysfs.c                          |  4 ++-
 net/core/rtnetlink.c                          | 23 +++++++++----
 17 files changed, 147 insertions(+), 44 deletions(-)

diff --git a/arch/s390/appldata/appldata_net_sum.c 
b/arch/s390/appldata/appldata_net_sum.c
index 6146606ac9a3..72cb5344e488 100644
--- a/arch/s390/appldata/appldata_net_sum.c
+++ b/arch/s390/appldata/appldata_net_sum.c
@@ -58,11 +58,11 @@ struct appldata_net_sum_data {
  */
 static void appldata_get_net_sum_data(void *data)
 {
-       int i;
        struct appldata_net_sum_data *net_data;
        struct net_device *dev;
        unsigned long rx_packets, tx_packets, rx_bytes, tx_bytes, rx_errors,
                        tx_errors, rx_dropped, tx_dropped, collisions;
+       int ret, i;
 
        net_data = data;
        net_data->sync_count_1++;
@@ -83,7 +83,13 @@ static void appldata_get_net_sum_data(void *data)
        for_each_netdev(&init_net, dev) {
                struct rtnl_link_stats64 stats;
 
-               dev_get_stats(dev, &stats);
+               ret = dev_get_stats(dev, &stats);
+               if (ret) {
+                       netif_lists_unlock(&init_net);
+                       netdev_err(dev, "dev_get_stats returned %d\n", ret);
+                       return;
+               }
+
                rx_packets += stats.rx_packets;
                tx_packets += stats.tx_packets;
                rx_bytes   += stats.rx_bytes;
diff --git a/drivers/leds/trigger/ledtrig-netdev.c 
b/drivers/leds/trigger/ledtrig-netdev.c
index 4382ee278309..c717b7e7dd81 100644
--- a/drivers/leds/trigger/ledtrig-netdev.c
+++ b/drivers/leds/trigger/ledtrig-netdev.c
@@ -351,6 +351,7 @@ static void netdev_trig_work(struct work_struct *work)
        unsigned int new_activity;
        unsigned long interval;
        int invert;
+       int err;
 
        /* If we dont have a device, insure we are off */
        if (!trigger_data->net_dev) {
@@ -363,7 +364,13 @@ static void netdev_trig_work(struct work_struct *work)
            !test_bit(NETDEV_LED_RX, &trigger_data->mode))
                return;
 
-       dev_get_stats(trigger_data->net_dev, &dev_stats);
+       err = dev_get_stats(trigger_data->net_dev, &dev_stats);
+       if (err) {
+               netdev_err(trigger_data->net_dev,
+                          "dev_get_stats returned %d\n", err);
+               return;
+       }
+
        new_activity =
            (test_bit(NETDEV_LED_TX, &trigger_data->mode) ?
                dev_stats.tx_packets : 0) +
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 17faf431d85b..b70ca0e41142 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1757,7 +1757,12 @@ int bond_enslave(struct net_device *bond_dev, struct 
net_device *slave_dev,
 
        slave_dev->priv_flags |= IFF_BONDING;
        /* initialize slave stats */
-       dev_get_stats(new_slave->dev, &new_slave->slave_stats);
+       res = dev_get_stats(new_slave->dev, &new_slave->slave_stats);
+       if (res) {
+               slave_err(bond_dev, slave_dev, "dev_get_stats returned %d\n",
+                         res);
+               goto err_close;
+       }
 
        if (bond_is_lb(bond)) {
                /* bond_alb_init_slave() must be called before all other stages 
since
@@ -2070,6 +2075,7 @@ static int __bond_release_one(struct net_device *bond_dev,
        struct sockaddr_storage ss;
        int old_flags = bond_dev->flags;
        netdev_features_t old_features = bond_dev->features;
+       int err;
 
        /* slave is not a slave or master is not master of this slave */
        if (!(slave_dev->flags & IFF_SLAVE) ||
@@ -2088,13 +2094,19 @@ static int __bond_release_one(struct net_device 
*bond_dev,
                return -EINVAL;
        }
 
+       /* recompute stats just before removing the slave */
+       err = bond_get_stats(bond->dev, &bond->bond_stats);
+       if (err) {
+               slave_info(bond_dev, slave_dev, "dev_get_stats returned %d\n",
+                          err);
+               unblock_netpoll_tx();
+               return err;
+       }
+
        bond_set_slave_inactive_flags(slave, BOND_SLAVE_NOTIFY_NOW);
 
        bond_sysfs_slave_del(slave);
 
-       /* recompute stats just before removing the slave */
-       bond_get_stats(bond->dev, &bond->bond_stats);
-
        bond_upper_dev_unlink(bond, slave);
        /* unregister rx_handler early so bond_handle_frame wouldn't be called
         * for this slave anymore.
@@ -3742,7 +3754,7 @@ static int bond_get_stats(struct net_device *bond_dev,
        struct list_head *iter;
        struct slave *slave;
        int nest_level = 0;
-
+       int res = 0;
 
        rcu_read_lock();
 #ifdef CONFIG_LOCKDEP
@@ -3753,7 +3765,9 @@ static int bond_get_stats(struct net_device *bond_dev,
        memcpy(stats, &bond->bond_stats, sizeof(*stats));
 
        bond_for_each_slave_rcu(bond, slave, iter) {
-               dev_get_stats(slave->dev, &temp);
+               res = dev_get_stats(slave->dev, &temp);
+               if (res)
+                       goto out;
 
                bond_fold_stats(stats, &temp, &slave->slave_stats);
 
@@ -3762,10 +3776,11 @@ static int bond_get_stats(struct net_device *bond_dev,
        }
 
        memcpy(&bond->bond_stats, stats, sizeof(*stats));
+out:
        spin_unlock(&bond->stats_lock);
        rcu_read_unlock();
 
-       return 0;
+       return res;
 }
 
 static int bond_do_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int 
cmd)
diff --git a/drivers/net/ethernet/apm/xgene/xgene_enet_ethtool.c 
b/drivers/net/ethernet/apm/xgene/xgene_enet_ethtool.c
index ada70425b48c..aab6a81f0438 100644
--- a/drivers/net/ethernet/apm/xgene/xgene_enet_ethtool.c
+++ b/drivers/net/ethernet/apm/xgene/xgene_enet_ethtool.c
@@ -266,9 +266,14 @@ static void xgene_get_ethtool_stats(struct net_device 
*ndev,
 {
        struct xgene_enet_pdata *pdata = netdev_priv(ndev);
        struct rtnl_link_stats64 stats;
-       int i;
+       int err, i;
+
+       err = dev_get_stats(ndev, &stats);
+       if (err) {
+               netdev_err(ndev, "dev_get_stats returned %d\n", err);
+               return;
+       }
 
-       dev_get_stats(ndev, &stats);
        for (i = 0; i < XGENE_STATS_LEN; i++)
                data[i] = *(u64 *)((char *)&stats + gstrings_stats[i].offset);
 
diff --git a/drivers/net/ethernet/hisilicon/hns/hns_ethtool.c 
b/drivers/net/ethernet/hisilicon/hns/hns_ethtool.c
index ee2172011051..d05fa7b3f6e0 100644
--- a/drivers/net/ethernet/hisilicon/hns/hns_ethtool.c
+++ b/drivers/net/ethernet/hisilicon/hns/hns_ethtool.c
@@ -840,6 +840,7 @@ static void hns_get_ethtool_stats(struct net_device *netdev,
        struct hns_nic_priv *priv = netdev_priv(netdev);
        struct hnae_handle *h = priv->ae_handle;
        struct rtnl_link_stats64 net_stats;
+       int err;
 
        if (!h->dev->ops->get_stats || !h->dev->ops->update_stats) {
                netdev_err(netdev, "get_stats or update_stats is null!\n");
@@ -848,7 +849,11 @@ static void hns_get_ethtool_stats(struct net_device 
*netdev,
 
        h->dev->ops->update_stats(h, &netdev->stats);
 
-       dev_get_stats(netdev, &net_stats);
+       err = dev_get_stats(netdev, &net_stats);
+       if (err) {
+               netdev_err(netdev, "dev_get_stats returned %d\n", err);
+               return;
+       }
 
        /* get netdev statistics */
        p[0] = net_stats.rx_packets;
diff --git a/drivers/net/ethernet/intel/e1000e/ethtool.c 
b/drivers/net/ethernet/intel/e1000e/ethtool.c
index 06442e6bef73..41bd3e0598ce 100644
--- a/drivers/net/ethernet/intel/e1000e/ethtool.c
+++ b/drivers/net/ethernet/intel/e1000e/ethtool.c
@@ -2060,15 +2060,20 @@ static void e1000_get_ethtool_stats(struct net_device 
*netdev,
 {
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct rtnl_link_stats64 net_stats;
-       int i;
        char *p = NULL;
+       int err, i;
 
        pm_runtime_get_sync(netdev->dev.parent);
 
-       dev_get_stats(netdev, &net_stats);
+       err = dev_get_stats(netdev, &net_stats);
 
        pm_runtime_put_sync(netdev->dev.parent);
 
+       if (err) {
+               netdev_err(netdev, "dev_get_stats returned %d\n", err);
+               return;
+       }
+
        for (i = 0; i < E1000_GLOBAL_STATS_LEN; i++) {
                switch (e1000_gstrings_stats[i].type) {
                case NETDEV_STATS:
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c 
b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
index 2b8084664403..a647e2774f76 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
@@ -1298,11 +1298,16 @@ static void ixgbe_get_ethtool_stats(struct net_device 
*netdev,
        struct rtnl_link_stats64 net_stats;
        unsigned int start;
        struct ixgbe_ring *ring;
-       int i, j;
        char *p = NULL;
+       int err, i, j;
 
        ixgbe_update_stats(adapter);
-       dev_get_stats(netdev, &net_stats);
+       err = dev_get_stats(netdev, &net_stats);
+       if (err) {
+               netdev_err(netdev, "dev_get_stats returned %d\n", err);
+               return;
+       }
+
        for (i = 0; i < IXGBE_GLOBAL_STATS_LEN; i++) {
                switch (ixgbe_gstrings_stats[i].type) {
                case NETDEV_STATS:
diff --git a/drivers/net/ethernet/intel/ixgbevf/ethtool.c 
b/drivers/net/ethernet/intel/ixgbevf/ethtool.c
index 3b9b7e5c2998..665e39301092 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ethtool.c
+++ b/drivers/net/ethernet/intel/ixgbevf/ethtool.c
@@ -423,11 +423,16 @@ static void ixgbevf_get_ethtool_stats(struct net_device 
*netdev,
        struct rtnl_link_stats64 net_stats;
        unsigned int start;
        struct ixgbevf_ring *ring;
-       int i, j;
+       int err, i, j;
        char *p;
 
        ixgbevf_update_stats(adapter);
-       dev_get_stats(netdev, &net_stats);
+       err = dev_get_stats(netdev, &net_stats);
+       if (err) {
+               netdev_err(netdev, "dev_get_stats returned %d\n", err);
+               return;
+       }
+
        for (i = 0; i < IXGBEVF_GLOBAL_STATS_LEN; i++) {
                switch (ixgbevf_gstrings_stats[i].type) {
                case NETDEV_STATS:
diff --git a/drivers/net/net_failover.c b/drivers/net/net_failover.c
index e032ad1c5e22..2815228a34d5 100644
--- a/drivers/net/net_failover.c
+++ b/drivers/net/net_failover.c
@@ -185,6 +185,7 @@ static int net_failover_get_stats(struct net_device *dev,
        struct net_failover_info *nfo_info = netdev_priv(dev);
        struct rtnl_link_stats64 temp;
        struct net_device *slave_dev;
+       int err = 0;
 
        spin_lock(&nfo_info->stats_lock);
        memcpy(stats, &nfo_info->failover_stats, sizeof(*stats));
@@ -193,24 +194,29 @@ static int net_failover_get_stats(struct net_device *dev,
 
        slave_dev = rcu_dereference(nfo_info->primary_dev);
        if (slave_dev) {
-               dev_get_stats(slave_dev, &temp);
+               err = dev_get_stats(slave_dev, &temp);
+               if (err)
+                       goto out;
                net_failover_fold_stats(stats, &temp, &nfo_info->primary_stats);
                memcpy(&nfo_info->primary_stats, &temp, sizeof(temp));
        }
 
        slave_dev = rcu_dereference(nfo_info->standby_dev);
        if (slave_dev) {
-               dev_get_stats(slave_dev, &temp);
+               err = dev_get_stats(slave_dev, &temp);
+               if (err)
+                       goto out;
                net_failover_fold_stats(stats, &temp, &nfo_info->standby_stats);
                memcpy(&nfo_info->standby_stats, &temp, sizeof(temp));
        }
 
+out:
        rcu_read_unlock();
 
        memcpy(&nfo_info->failover_stats, stats, sizeof(*stats));
        spin_unlock(&nfo_info->stats_lock);
 
-       return 0;
+       return err;
 }
 
 static int net_failover_change_mtu(struct net_device *dev, int new_mtu)
@@ -545,11 +551,15 @@ static int net_failover_slave_register(struct net_device 
*slave_dev,
        if (slave_is_standby) {
                rcu_assign_pointer(nfo_info->standby_dev, slave_dev);
                standby_dev = slave_dev;
-               dev_get_stats(standby_dev, &nfo_info->standby_stats);
+               err = dev_get_stats(standby_dev, &nfo_info->standby_stats);
+               if (err)
+                       goto err_stats_get;
        } else {
                rcu_assign_pointer(nfo_info->primary_dev, slave_dev);
                primary_dev = slave_dev;
-               dev_get_stats(primary_dev, &nfo_info->primary_stats);
+               err = dev_get_stats(primary_dev, &nfo_info->primary_stats);
+               if (err)
+                       goto err_stats_get;
                failover_dev->min_mtu = slave_dev->min_mtu;
                failover_dev->max_mtu = slave_dev->max_mtu;
        }
@@ -564,6 +574,8 @@ static int net_failover_slave_register(struct net_device 
*slave_dev,
 
        return 0;
 
+err_stats_get:
+       vlan_vids_del_by_dev(slave_dev, failover_dev);
 err_vlan_add:
        dev_uc_unsync(slave_dev, failover_dev);
        dev_mc_unsync(slave_dev, failover_dev);
@@ -597,6 +609,7 @@ static int net_failover_slave_unregister(struct net_device 
*slave_dev,
        struct net_device *standby_dev, *primary_dev;
        struct net_failover_info *nfo_info;
        bool slave_is_standby;
+       int err;
 
        nfo_info = netdev_priv(failover_dev);
        primary_dev = rtnl_dereference(nfo_info->primary_dev);
@@ -611,7 +624,8 @@ static int net_failover_slave_unregister(struct net_device 
*slave_dev,
        dev_close(slave_dev);
 
        nfo_info = netdev_priv(failover_dev);
-       dev_get_stats(failover_dev, &nfo_info->failover_stats);
+       /* Proceed with the deregistration anyway */
+       err = dev_get_stats(failover_dev, &nfo_info->failover_stats);
 
        slave_is_standby = slave_dev->dev.parent == failover_dev->dev.parent;
        if (slave_is_standby) {
@@ -631,7 +645,7 @@ static int net_failover_slave_unregister(struct net_device 
*slave_dev,
        netdev_info(failover_dev, "failover %s slave:%s unregistered\n",
                    slave_is_standby ? "standby" : "primary", slave_dev->name);
 
-       return 0;
+       return err;
 }
 
 static int net_failover_slave_link_change(struct net_device *slave_dev,
@@ -639,6 +653,7 @@ static int net_failover_slave_link_change(struct net_device 
*slave_dev,
 {
        struct net_device *primary_dev, *standby_dev;
        struct net_failover_info *nfo_info;
+       int err;
 
        nfo_info = netdev_priv(failover_dev);
 
@@ -653,7 +668,9 @@ static int net_failover_slave_link_change(struct net_device 
*slave_dev,
                netif_carrier_on(failover_dev);
                netif_tx_wake_all_queues(failover_dev);
        } else {
-               dev_get_stats(failover_dev, &nfo_info->failover_stats);
+               err = dev_get_stats(failover_dev, &nfo_info->failover_stats);
+               if (err)
+                       return err;
                netif_carrier_off(failover_dev);
                netif_tx_stop_all_queues(failover_dev);
        }
diff --git a/drivers/parisc/led.c b/drivers/parisc/led.c
index cc6108785323..d17d0fbf878d 100644
--- a/drivers/parisc/led.c
+++ b/drivers/parisc/led.c
@@ -370,7 +370,12 @@ static __inline__ int led_get_net_activity(void)
 
                in_dev_put(in_dev);
 
-               dev_get_stats(dev, &stats);
+               retval = dev_get_stats(dev, &stats);
+               if (retval) {
+                       netif_lists_unlock(&init_net);
+                       return retval;
+               }
+
                rx_total += stats.rx_packets;
                tx_total += stats.tx_packets;
        }
diff --git a/drivers/usb/gadget/function/rndis.c 
b/drivers/usb/gadget/function/rndis.c
index 7ec29e007ae9..bec474819c3d 100644
--- a/drivers/usb/gadget/function/rndis.c
+++ b/drivers/usb/gadget/function/rndis.c
@@ -198,7 +198,9 @@ static int gen_ndis_query_resp(struct rndis_params *params, 
u32 OID, u8 *buf,
        resp->InformationBufferOffset = cpu_to_le32(16);
 
        net = params->dev;
-       dev_get_stats(net, &stats);
+       retval = dev_get_stats(net, &stats);
+       if (retval)
+               return retval;
 
        switch (OID) {
 
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index bd471f1e1fa3..b1aebab916a8 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -4545,7 +4545,8 @@ void netdev_notify_peers(struct net_device *dev);
 void netdev_features_change(struct net_device *dev);
 /* Load a device via the kmod */
 void dev_load(struct net *net, const char *name);
-int dev_get_stats(struct net_device *dev, struct rtnl_link_stats64 *storage);
+int __must_check dev_get_stats(struct net_device *dev,
+                              struct rtnl_link_stats64 *storage);
 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
                             const struct net_device_stats *netdev_stats);
 void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s,
diff --git a/net/8021q/vlanproc.c b/net/8021q/vlanproc.c
index 3a6682d79630..d89b75804834 100644
--- a/net/8021q/vlanproc.c
+++ b/net/8021q/vlanproc.c
@@ -244,12 +244,15 @@ static int vlandev_seq_show(struct seq_file *seq, void 
*offset)
        const struct vlan_dev_priv *vlan = vlan_dev_priv(vlandev);
        static const char fmt64[] = "%30s %12llu\n";
        struct rtnl_link_stats64 stats;
-       int i;
+       int err, i;
 
        if (!is_vlan_dev(vlandev))
                return 0;
 
-       dev_get_stats(vlandev, &stats);
+       err = dev_get_stats(vlandev, &stats);
+       if (err)
+               return err;
+
        seq_printf(seq,
                   "%s  VID: %d  REORDER_HDR: %i  dev->priv_flags: %hx\n",
                   vlandev->name, vlan->vlan_id,
diff --git a/net/core/dev.c b/net/core/dev.c
index dfbd66ba3cad..30facac95d5e 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -10403,7 +10403,8 @@ EXPORT_SYMBOL(netdev_stats_to_stats64);
  *     dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
  *     otherwise the internal statistics structure is used.
  */
-int dev_get_stats(struct net_device *dev, struct rtnl_link_stats64 *storage)
+int __must_check dev_get_stats(struct net_device *dev,
+                              struct rtnl_link_stats64 *storage)
 {
        const struct net_device_ops *ops = dev->netdev_ops;
        int err = 0;
diff --git a/net/core/net-procfs.c b/net/core/net-procfs.c
index 64666ba7ccab..ee19c35f6e00 100644
--- a/net/core/net-procfs.c
+++ b/net/core/net-procfs.c
@@ -78,11 +78,14 @@ static void dev_seq_stop(struct seq_file *seq, void *v)
        netif_lists_unlock(net);
 }
 
-static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev)
+static int dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev)
 {
        struct rtnl_link_stats64 stats;
+       int err;
 
-       dev_get_stats(dev, &stats);
+       err = dev_get_stats(dev, &stats);
+       if (err)
+               return err;
 
        seq_printf(seq, "%6s: %7llu %7llu %4llu %4llu %4llu %5llu %10llu %9llu "
                   "%8llu %7llu %4llu %4llu %4llu %5llu %7llu %10llu\n",
@@ -101,6 +104,8 @@ static void dev_seq_printf_stats(struct seq_file *seq, 
struct net_device *dev)
                    stats.tx_window_errors +
                    stats.tx_heartbeat_errors,
                   stats.tx_compressed);
+
+       return 0;
 }
 
 /*
@@ -109,6 +114,8 @@ static void dev_seq_printf_stats(struct seq_file *seq, 
struct net_device *dev)
  */
 static int dev_seq_show(struct seq_file *seq, void *v)
 {
+       int err = 0;
+
        if (v == SEQ_START_TOKEN)
                seq_puts(seq, "Inter-|   Receive                            "
                              "                    |  Transmit\n"
@@ -116,8 +123,9 @@ static int dev_seq_show(struct seq_file *seq, void *v)
                              "compressed multicast|bytes    packets errs "
                              "drop fifo colls carrier compressed\n");
        else
-               dev_seq_printf_stats(seq, v);
-       return 0;
+               err = dev_seq_printf_stats(seq, v);
+
+       return err;
 }
 
 static u32 softnet_backlog_len(struct softnet_data *sd)
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 5d89c85b42d4..6f789e178e92 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -588,7 +588,9 @@ static ssize_t netstat_show(const struct device *d,
        if (dev_isalive(dev)) {
                struct rtnl_link_stats64 stats;
 
-               dev_get_stats(dev, &stats);
+               ret = dev_get_stats(dev, &stats);
+               if (ret)
+                       return ret;
 
                ret = sprintf(buf, fmt_u64, *(u64 *)(((u8 *)&stats) + offset));
        }
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index bb0596c41b3e..6cc87094924d 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1201,6 +1201,7 @@ static noinline_for_stack int rtnl_fill_stats(struct 
sk_buff *skb,
 {
        struct rtnl_link_stats64 *sp;
        struct nlattr *attr;
+       int err;
 
        attr = nla_reserve_64bit(skb, IFLA_STATS64,
                                 sizeof(struct rtnl_link_stats64), IFLA_PAD);
@@ -1208,7 +1209,9 @@ static noinline_for_stack int rtnl_fill_stats(struct 
sk_buff *skb,
                return -EMSGSIZE;
 
        sp = nla_data(attr);
-       dev_get_stats(dev, sp);
+       err = dev_get_stats(dev, sp);
+       if (err)
+               return err;
 
        attr = nla_reserve(skb, IFLA_STATS,
                           sizeof(struct rtnl_link_stats));
@@ -1707,6 +1710,7 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb,
 {
        struct ifinfomsg *ifm;
        struct nlmsghdr *nlh;
+       int err;
 
        ASSERT_RTNL();
        nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags);
@@ -1780,8 +1784,9 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb,
        if (rtnl_phys_switch_id_fill(skb, dev))
                goto nla_put_failure;
 
-       if (rtnl_fill_stats(skb, dev))
-               goto nla_put_failure;
+       err = rtnl_fill_stats(skb, dev);
+       if (err)
+               goto get_stats_failure;
 
        if (rtnl_fill_vf(skb, dev, ext_filter_mask))
                goto nla_put_failure;
@@ -1825,8 +1830,10 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb,
 nla_put_failure_rcu:
        rcu_read_unlock();
 nla_put_failure:
+       err = -EMSGSIZE;
+get_stats_failure:
        nlmsg_cancel(skb, nlh);
-       return -EMSGSIZE;
+       return err;
 }
 
 static const struct nla_policy ifla_policy[IFLA_MAX+1] = {
@@ -5135,7 +5142,9 @@ static int rtnl_fill_statsinfo(struct sk_buff *skb, 
struct net_device *dev,
                        goto nla_put_failure;
 
                sp = nla_data(attr);
-               dev_get_stats(dev, sp);
+               err = dev_get_stats(dev, sp);
+               if (err)
+                       goto get_stats_failure;
        }
 
        if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_XSTATS, *idxattr)) {
@@ -5242,13 +5251,15 @@ static int rtnl_fill_statsinfo(struct sk_buff *skb, 
struct net_device *dev,
        return 0;
 
 nla_put_failure:
+       err = -EMSGSIZE;
+get_stats_failure:
        /* not a multi message or no progress mean a real error */
        if (!(flags & NLM_F_MULTI) || s_prividx == *prividx)
                nlmsg_cancel(skb, nlh);
        else
                nlmsg_end(skb, nlh);
 
-       return -EMSGSIZE;
+       return err;
 }
 
 static size_t if_nlmsg_stats_size(const struct net_device *dev,
-- 
2.25.1

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