[PATCH v2] drdb: fix debugfs_create_dir and debugfs_create_symlink error handling

[mirimmad]

From: Immad Mir <mirimmad17@xxxxxxxxx>

debugfs_create_dir and debugfs_create_symlink return ERR_PTR incase of
a failure which must be checked with the inline function IS_ERR. This
patch attempts to do the same.

Signed-off-by: Immad Mir <mirimmad17@xxxxxxxxx>
---
Changes in v2:
    - Fix indentation
    - Fix potential memory leak

 drivers/block/drbd/drbd_debugfs.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/block/drbd/drbd_debugfs.c b/drivers/block/drbd/drbd_debugfs.c
index 12460b584..ab431a3f2 100644
--- a/drivers/block/drbd/drbd_debugfs.c
+++ b/drivers/block/drbd/drbd_debugfs.c
@@ -781,6 +781,7 @@ void drbd_debugfs_device_add(struct drbd_device *device)

 	snprintf(vnr_buf, sizeof(vnr_buf), "%u", device->vnr);
 	dentry = debugfs_create_dir(vnr_buf, vols_dir);
+    if (IS_ERR(dentry)) goto fail;
 	device->debugfs_vol = dentry;

 	snprintf(minor_buf, sizeof(minor_buf), "%u", device->minor);
@@ -789,9 +790,15 @@ void drbd_debugfs_device_add(struct drbd_device *device)
 	if (!slink_name)
 		goto fail;
 	dentry = debugfs_create_symlink(minor_buf, drbd_debugfs_minors, slink_name);
-	device->debugfs_minor = dentry;
-	kfree(slink_name);
-	slink_name = NULL;
+    if (!IS_ERR(dentry)) {
+        device->debugfs_minor = dentry;
+        kfree(slink_name);
+        slink_name = NULL;
+    } else {
+        kfree(slink_name);
+        slink_name = NULL;
+        goto fail;
+    }

 #define DCF(name)	do {					\
 	dentry = debugfs_create_file(#name, 0440,	\
--
2.40.0