net/mlx4_core: Fixed memory leak and incorrect refcount in mlx4_load_one

The current mlx4_load_one has a memory leak as it always allocates
dev_cap, but frees it only on error.

In addition, even if VFs exist when mlx4_load_one is called,
we still need to notify probed VFs that we're loading (by
incrementing pf_loading).

Fixes: a0eacca948d2 ('net/mlx4_core: Refactor mlx4_load_one')
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 33 insertions, 28 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index e25436b24ce7..c2ef266ad7c1 100644
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -2488,41 +2488,42 @@ static u64 mlx4_enable_sriov(struct mlx4_dev *dev, struct pci_dev *pdev,
                              u8 total_vfs, int existing_vfs)
 {
         u64 dev_flags = dev->flags;
+        int err = 0;
 
-        dev->dev_vfs = kzalloc(
-                        total_vfs * sizeof(*dev->dev_vfs),
-                        GFP_KERNEL);
+        atomic_inc(&pf_loading);
+        if (dev->flags &  MLX4_FLAG_SRIOV) {
+                if (existing_vfs != total_vfs) {
+                        mlx4_err(dev, "SR-IOV was already enabled, but with num_vfs (%d) different than requested (%d)\n",
+                                 existing_vfs, total_vfs);
+                        total_vfs = existing_vfs;
+                }
+        }
+
+        dev->dev_vfs = kzalloc(total_vfs * sizeof(*dev->dev_vfs), GFP_KERNEL);
         if (NULL == dev->dev_vfs) {
                 mlx4_err(dev, "Failed to allocate memory for VFs\n");
                 goto disable_sriov;
-        } else if (!(dev->flags &  MLX4_FLAG_SRIOV)) {
-                int err = 0;
-
-                atomic_inc(&pf_loading);
-                if (existing_vfs) {
-                        if (existing_vfs != total_vfs)
-                                mlx4_err(dev, "SR-IOV was already enabled, but with num_vfs (%d) different than requested (%d)\n",
-                                         existing_vfs, total_vfs);
-                } else {
-                        mlx4_warn(dev, "Enabling SR-IOV with %d VFs\n", total_vfs);
-                        err = pci_enable_sriov(pdev, total_vfs);
-                }
-                if (err) {
-                        mlx4_err(dev, "Failed to enable SR-IOV, continuing without SR-IOV (err = %d)\n",
-                                 err);
-                        atomic_dec(&pf_loading);
-                        goto disable_sriov;
-                } else {
-                        mlx4_warn(dev, "Running in master mode\n");
-                        dev_flags |= MLX4_FLAG_SRIOV |
-                                MLX4_FLAG_MASTER;
-                        dev_flags &= ~MLX4_FLAG_SLAVE;
-                        dev->num_vfs = total_vfs;
-                }
+        }
+
+        if (!(dev->flags &  MLX4_FLAG_SRIOV)) {
+                mlx4_warn(dev, "Enabling SR-IOV with %d VFs\n", total_vfs);
+                err = pci_enable_sriov(pdev, total_vfs);
+        }
+        if (err) {
+                mlx4_err(dev, "Failed to enable SR-IOV, continuing without SR-IOV (err = %d)\n",
+                         err);
+                goto disable_sriov;
+        } else {
+                mlx4_warn(dev, "Running in master mode\n");
+                dev_flags |= MLX4_FLAG_SRIOV |
+                        MLX4_FLAG_MASTER;
+                dev_flags &= ~MLX4_FLAG_SLAVE;
+                dev->num_vfs = total_vfs;
         }
         return dev_flags;
 
 disable_sriov:
+        atomic_dec(&pf_loading);
         dev->num_vfs = 0;
         kfree(dev->dev_vfs);
         return dev_flags & ~MLX4_FLAG_MASTER;
@@ -2606,8 +2607,10 @@ static int mlx4_load_one(struct pci_dev *pdev, int pci_dev_data,
                 }
 
                 if (total_vfs) {
-                        existing_vfs = pci_num_vf(pdev);
                         dev->flags = MLX4_FLAG_MASTER;
+                        existing_vfs = pci_num_vf(pdev);
+                        if (existing_vfs)
+                                dev->flags |= MLX4_FLAG_SRIOV;
                         dev->num_vfs = total_vfs;
                 }
         }
@@ -2643,6 +2646,7 @@ slave_start:
         }
 
         if (mlx4_is_master(dev)) {
+                /* when we hit the goto slave_start below, dev_cap already initialized */
                 if (!dev_cap) {
                         dev_cap = kzalloc(sizeof(*dev_cap), GFP_KERNEL);
 
@@ -2849,6 +2853,7 @@ slave_start:
         if (mlx4_is_master(dev) && dev->num_vfs)
                 atomic_dec(&pf_loading);
 
+        kfree(dev_cap);
         return 0;
 
 err_port: