debugfs: debugfs_create_file_size(): use IS_ERR to check for error

stable inclusion
from stable-5.10.71
commit 3bef1b7242e0a344177ba95ddafb3d2c67693ab2
bugzilla: 182981 https://gitee.com/openeuler/kernel/issues/I4I3KD

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3bef1b7242e0a344177ba95ddafb3d2c67693ab2

--------------------------------

commit af505cad upstream.

debugfs_create_file() returns encoded error so use IS_ERR for checking
return value.
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NNirmoy Das <nirmoy.das@amd.com>
Fixes: ff9fb72b ("debugfs: return error values, not NULL")
Cc: stable <stable@vger.kernel.org>
References: https://gitlab.freedesktop.org/drm/amd/-/issues/1686
Link: https://lore.kernel.org/r/20210902102917.2233-1-nirmoy.das@amd.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

fs/debugfs/inode.c

@@ -527,7 +527,7 @@ void debugfs_create_file_size(const char *name, umode_t mode,
 {
 	struct dentry *de = debugfs_create_file(name, mode, parent, data, fops);
 
-	if (de)
+	if (!IS_ERR(de))
 		d_inode(de)->i_size = file_size;
 }
 EXPORT_SYMBOL_GPL(debugfs_create_file_size);