In the Linux kernel, the following vulnerability has been resolved: net: sparx5: switchdev: fix possible NULL pointer dereference As the possible failure of the allocation, devm_kzalloc() may return NULL pointer. Therefore, it should be better to check the 'db' in order to prevent the dereference of NULL pointer.
https://git.kernel.org/stable/c/e7e1fff76c4c57688dc7d53a3b6212182d5628d0
https://git.kernel.org/stable/c/c346791877e6ce923bb21e34b30c6f99326aa5a8
https://git.kernel.org/stable/c/b375ea083fa649092cd016ac1f89a2d1fd8f8e8b
https://git.kernel.org/stable/c/0906f3a3df07835e37077d8971aac65347f2ed57