From: Karsten Graul <kgraul@xxxxxxxxxxxxx>
[ Upstream commit 587acad41f1bc48e16f42bb2aca63bf323380be8 ]
Coverity reports a possible NULL dereferencing problem:
in smc_vlan_by_tcpsk():
6. returned_null: netdev_lower_get_next returns NULL (checked 29 out of 30 times).
7. var_assigned: Assigning: ndev = NULL return value from netdev_lower_get_next.
1623 ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower);
CID 1468509 (#1 of 1): Dereference null return value (NULL_RETURNS)
8. dereference: Dereferencing a pointer that might be NULL ndev when calling is_vlan_dev.
1624 if (is_vlan_dev(ndev)) {
Remove the manual implementation and use netdev_walk_all_lower_dev() to
iterate over the lower devices. While on it remove an obsolete function
parameter comment.
Fixes: cb9d43f67754 ("net/smc: determine vlan_id of stacked net_device")
Suggested-by: Julian Wiedmann <jwi@xxxxxxxxxxxxx>
Signed-off-by: Karsten Graul <kgraul@xxxxxxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/smc/smc_core.c | 35 ++++++++++++++++++-----------------
1 file changed, 18 insertions(+), 17 deletions(-)
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index d672c0f0e247f..508a14fc4f587 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -1596,14 +1596,26 @@ static void smc_link_down_work(struct work_struct *work)
mutex_unlock(&lgr->llc_conf_mutex);
}
-/* Determine vlan of internal TCP socket.
- * @vlan_id: address to store the determined vlan id into
- */
+static int smc_vlan_by_tcpsk_walk(struct net_device *lower_dev,
+ struct netdev_nested_priv *priv)
+{
+ unsigned short *vlan_id = (unsigned short *)priv->data;
+
+ if (is_vlan_dev(lower_dev)) {
+ *vlan_id = vlan_dev_vlan_id(lower_dev);
+ return 1;
+ }
+
+ return 0;
+}
+
+/* Determine vlan of internal TCP socket. */
int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
{
struct dst_entry *dst = sk_dst_get(clcsock->sk);
+ struct netdev_nested_priv priv;
struct net_device *ndev;
- int i, nest_lvl, rc = 0;
+ int rc = 0;
ini->vlan_id = 0;
if (!dst) {
@@ -1621,20 +1633,9 @@ int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
goto out_rel;
}
+ priv.data = (void *)&ini->vlan_id;
rtnl_lock();
- nest_lvl = ndev->lower_level;
- for (i = 0; i < nest_lvl; i++) {
- struct list_head *lower = &ndev->adj_list.lower;
-
- if (list_empty(lower))
- break;
- lower = lower->next;
- ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower);
- if (is_vlan_dev(ndev)) {
- ini->vlan_id = vlan_dev_vlan_id(ndev);
- break;
- }
- }
+ netdev_walk_all_lower_dev(ndev, smc_vlan_by_tcpsk_walk, &priv);
rtnl_unlock();
out_rel:
--
2.33.0
