From d6ca199568c53ece99aeeae1022d04f2fd8cde7f Mon Sep 17 00:00:00 2001 From: Zeeshan Ahmad Date: Mon, 2 Mar 2026 11:43:17 +0500 Subject: [PATCH] net: core: failover: enforce mandatory ops and clean up redundant checks The failover framework requires 'ops' to be functional. Currently, failover_register() allows an instance to be registered with NULL ops, which leads to inconsistent NULL checks and potential NULL pointer dereferences in the slave registration paths. Harden the entry point by requiring non-NULL ops in failover_register(). This ensures the 'fops' pointer is guaranteed to be valid for any successfully registered failover instance. Consequently, remove the now redundant NULL checks for 'fops' throughout the module to simplify the logic. Signed-off-by: Zeeshan Ahmad Link: https://patch.msgid.link/20260302064317.9964-1-zeeshanahmad022019@gmail.com Signed-off-by: Jakub Kicinski --- net/core/failover.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/net/core/failover.c b/net/core/failover.c index 0eb2e0ec875b3..11bb183c7a1ba 100644 --- a/net/core/failover.c +++ b/net/core/failover.c @@ -59,7 +59,7 @@ static int failover_slave_register(struct net_device *slave_dev) if (!failover_dev) goto done; - if (fops && fops->slave_pre_register && + if (fops->slave_pre_register && fops->slave_pre_register(slave_dev, failover_dev)) goto done; @@ -82,7 +82,7 @@ static int failover_slave_register(struct net_device *slave_dev) slave_dev->priv_flags |= (IFF_FAILOVER_SLAVE | IFF_NO_ADDRCONF); - if (fops && fops->slave_register && + if (fops->slave_register && !fops->slave_register(slave_dev, failover_dev)) return NOTIFY_OK; @@ -115,7 +115,7 @@ int failover_slave_unregister(struct net_device *slave_dev) if (!failover_dev) goto done; - if (fops && fops->slave_pre_unregister && + if (fops->slave_pre_unregister && fops->slave_pre_unregister(slave_dev, failover_dev)) goto done; @@ -123,7 +123,7 @@ int failover_slave_unregister(struct net_device *slave_dev) netdev_upper_dev_unlink(slave_dev, failover_dev); slave_dev->priv_flags &= ~(IFF_FAILOVER_SLAVE | IFF_NO_ADDRCONF); - if (fops && fops->slave_unregister && + if (fops->slave_unregister && !fops->slave_unregister(slave_dev, failover_dev)) return NOTIFY_OK; @@ -149,7 +149,7 @@ static int failover_slave_link_change(struct net_device *slave_dev) if (!netif_running(failover_dev)) goto done; - if (fops && fops->slave_link_change && + if (fops->slave_link_change && !fops->slave_link_change(slave_dev, failover_dev)) return NOTIFY_OK; @@ -174,7 +174,7 @@ static int failover_slave_name_change(struct net_device *slave_dev) if (!netif_running(failover_dev)) goto done; - if (fops && fops->slave_name_change && + if (fops->slave_name_change && !fops->slave_name_change(slave_dev, failover_dev)) return NOTIFY_OK; @@ -244,7 +244,7 @@ struct failover *failover_register(struct net_device *dev, { struct failover *failover; - if (dev->type != ARPHRD_ETHER) + if (dev->type != ARPHRD_ETHER || !ops) return ERR_PTR(-EINVAL); failover = kzalloc_obj(*failover); -- 2.47.3