[PATCH net-next v2] netdevsim: correctly check return value of debugfs_create_dir

[Prashant Bhole]

- Checking return value with IS_ERROR_OR_NULL
- Added error handling where it was not handled

Signed-off-by: Prashant Bhole <bhole_prashant...@lab.ntt.co.jp>
---
 drivers/net/netdevsim/bpf.c    |  8 ++++----
 drivers/net/netdevsim/netdev.c | 12 ++++++++----
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/drivers/net/netdevsim/bpf.c b/drivers/net/netdevsim/bpf.c
index 078d2c37a6c1..aeb429428cc5 100644
--- a/drivers/net/netdevsim/bpf.c
+++ b/drivers/net/netdevsim/bpf.c
@@ -201,7 +201,6 @@ static int nsim_bpf_create_prog(struct netdevsim *ns, 
struct bpf_prog *prog)
 {
        struct nsim_bpf_bound_prog *state;
        char name[16];
-       int err;
 
        state = kzalloc(sizeof(*state), GFP_KERNEL);
        if (!state)
@@ -214,10 +213,9 @@ static int nsim_bpf_create_prog(struct netdevsim *ns, 
struct bpf_prog *prog)
        /* Program id is not populated yet when we create the state. */
        sprintf(name, "%u", ns->prog_id_gen++);
        state->ddir = debugfs_create_dir(name, ns->ddir_bpf_bound_progs);
-       if (IS_ERR(state->ddir)) {
-               err = PTR_ERR(state->ddir);
+       if (IS_ERR_OR_NULL(state->ddir)) {
                kfree(state);
-               return err;
+               return -ENOMEM;
        }
 
        debugfs_create_u32("id", 0400, state->ddir, &prog->aux->id);
@@ -349,6 +347,8 @@ int nsim_bpf_init(struct netdevsim *ns)
                           &ns->bpf_bind_verifier_delay);
        ns->ddir_bpf_bound_progs =
                debugfs_create_dir("bpf_bound_progs", ns->ddir);
+       if (IS_ERR_OR_NULL(ns->ddir_bpf_bound_progs))
+               return -ENOMEM;
 
        ns->bpf_tc_accept = true;
        debugfs_create_bool("bpf_tc_accept", 0600, ns->ddir,
diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c
index eb8c679fca9f..c2a02d1944b8 100644
--- a/drivers/net/netdevsim/netdev.c
+++ b/drivers/net/netdevsim/netdev.c
@@ -147,10 +147,12 @@ struct device_type nsim_dev_type = {
 static int nsim_init(struct net_device *dev)
 {
        struct netdevsim *ns = netdev_priv(dev);
-       int err;
+       int err = -ENOMEM;
 
        ns->netdev = dev;
        ns->ddir = debugfs_create_dir(netdev_name(dev), nsim_ddir);
+       if (IS_ERR_OR_NULL(ns->ddir))
+               goto err;
 
        err = nsim_bpf_init(ns);
        if (err)
@@ -171,6 +173,7 @@ static int nsim_init(struct net_device *dev)
        nsim_bpf_uninit(ns);
 err_debugfs_destroy:
        debugfs_remove_recursive(ns->ddir);
+err:
        return err;
 }
 
@@ -466,11 +469,11 @@ struct dentry *nsim_ddir;
 
 static int __init nsim_module_init(void)
 {
-       int err;
+       int err = -ENOMEM;
 
        nsim_ddir = debugfs_create_dir(DRV_NAME, NULL);
-       if (IS_ERR(nsim_ddir))
-               return PTR_ERR(nsim_ddir);
+       if (IS_ERR_OR_NULL(nsim_ddir))
+               goto err;
 
        err = bus_register(&nsim_bus);
        if (err)
@@ -486,6 +489,7 @@ static int __init nsim_module_init(void)
        bus_unregister(&nsim_bus);
 err_debugfs_destroy:
        debugfs_remove_recursive(nsim_ddir);
+err:
        return err;
 }
 
-- 
2.13.6