target/linux/generic/backport-5.10/808-v5.18-0003-nvmem-core-Check-input-parameter-for-NULL-in-nvmem_u.patch

   1 From 8c751e0d9a5264376935a84429a2d468c8877d99 Mon Sep 17 00:00:00 2001
   2 From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
   3 Date: Sun, 20 Feb 2022 15:15:17 +0000
   4 Subject: [PATCH] nvmem: core: Check input parameter for NULL in
   5  nvmem_unregister()
   6
   7 nvmem_unregister() frees resources and standard pattern is to allow
   8 caller to not care if it's NULL or not. This will reduce burden on
   9 the callers to perform this check.
  10
  11 Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
  12 Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
  13 Link: https://lore.kernel.org/r/20220220151527.17216-4-srinivas.kandagatla@linaro.org
  14 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  15 ---
  16  drivers/nvmem/core.c | 3 ++-
  17  1 file changed, 2 insertions(+), 1 deletion(-)
  18
  19 --- a/drivers/nvmem/core.c
  20 +++ b/drivers/nvmem/core.c
  21 @@ -903,7 +903,8 @@ static void nvmem_device_release(struct
  22   */
  23  void nvmem_unregister(struct nvmem_device *nvmem)
  24  {
  25 -       kref_put(&nvmem->refcnt, nvmem_device_release);
  26 +       if (nvmem)
  27 +               kref_put(&nvmem->refcnt, nvmem_device_release);
  28  }
  29  EXPORT_SYMBOL_GPL(nvmem_unregister);
  30