6.16-stable review patch. If anyone has any objections, please let me know.
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From: Hangbin Liu liuhangbin@gmail.com
[ Upstream commit 847748fc66d08a89135a74e29362a66ba4e3ab15 ]
hsr_get_port_ndev calls hsr_for_each_port, which need to hold rcu lock. On the other hand, before return the port device, we need to hold the device reference to avoid UaF in the caller function.
Suggested-by: Paolo Abeni pabeni@redhat.com Fixes: 9c10dd8eed74 ("net: hsr: Create and export hsr_get_port_ndev()") Signed-off-by: Hangbin Liu liuhangbin@gmail.com Reviewed-by: Simon Horman horms@kernel.org Link: https://patch.msgid.link/20250905091533.377443-4-liuhangbin@gmail.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/ti/icssg/icssg_prueth.c | 20 ++++++++++++++------ net/hsr/hsr_device.c | 7 ++++++- 2 files changed, 20 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/ti/icssg/icssg_prueth.c b/drivers/net/ethernet/ti/icssg/icssg_prueth.c index f436d7cf565a1..1a9cc8206430b 100644 --- a/drivers/net/ethernet/ti/icssg/icssg_prueth.c +++ b/drivers/net/ethernet/ti/icssg/icssg_prueth.c @@ -691,7 +691,7 @@ static void icssg_prueth_hsr_fdb_add_del(struct prueth_emac *emac,
static int icssg_prueth_hsr_add_mcast(struct net_device *ndev, const u8 *addr) { - struct net_device *real_dev; + struct net_device *real_dev, *port_dev; struct prueth_emac *emac; u8 vlan_id, i;
@@ -700,11 +700,15 @@ static int icssg_prueth_hsr_add_mcast(struct net_device *ndev, const u8 *addr)
if (is_hsr_master(real_dev)) { for (i = HSR_PT_SLAVE_A; i < HSR_PT_INTERLINK; i++) { - emac = netdev_priv(hsr_get_port_ndev(real_dev, i)); - if (!emac) + port_dev = hsr_get_port_ndev(real_dev, i); + emac = netdev_priv(port_dev); + if (!emac) { + dev_put(port_dev); return -EINVAL; + } icssg_prueth_hsr_fdb_add_del(emac, addr, vlan_id, true); + dev_put(port_dev); } } else { emac = netdev_priv(real_dev); @@ -716,7 +720,7 @@ static int icssg_prueth_hsr_add_mcast(struct net_device *ndev, const u8 *addr)
static int icssg_prueth_hsr_del_mcast(struct net_device *ndev, const u8 *addr) { - struct net_device *real_dev; + struct net_device *real_dev, *port_dev; struct prueth_emac *emac; u8 vlan_id, i;
@@ -725,11 +729,15 @@ static int icssg_prueth_hsr_del_mcast(struct net_device *ndev, const u8 *addr)
if (is_hsr_master(real_dev)) { for (i = HSR_PT_SLAVE_A; i < HSR_PT_INTERLINK; i++) { - emac = netdev_priv(hsr_get_port_ndev(real_dev, i)); - if (!emac) + port_dev = hsr_get_port_ndev(real_dev, i); + emac = netdev_priv(port_dev); + if (!emac) { + dev_put(port_dev); return -EINVAL; + } icssg_prueth_hsr_fdb_add_del(emac, addr, vlan_id, false); + dev_put(port_dev); } } else { emac = netdev_priv(real_dev); diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c index 702da1f9aaa90..fbbc3ccf9df64 100644 --- a/net/hsr/hsr_device.c +++ b/net/hsr/hsr_device.c @@ -675,9 +675,14 @@ struct net_device *hsr_get_port_ndev(struct net_device *ndev, struct hsr_priv *hsr = netdev_priv(ndev); struct hsr_port *port;
+ rcu_read_lock(); hsr_for_each_port(hsr, port) - if (port->type == pt) + if (port->type == pt) { + dev_hold(port->dev); + rcu_read_unlock(); return port->dev; + } + rcu_read_unlock(); return NULL; } EXPORT_SYMBOL(hsr_get_port_ndev);