CVE-2022-48908

In the Linux kernel, the following vulnerability has been resolved:

net: arcnet: com20020: Fix null-ptr-deref in com20020pci_probe()

During driver initialization, the pointer of card info, i.e. the variable 'ci' is required. However, the definition of 'com20020pci_id_table' reveals that this field is empty for some devices, which will cause null pointer dereference when initializing these devices.

The following log reveals it:

[ 3.973806] KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] [ 3.973819] RIP: 0010:com20020pci_probe+0x18d/0x13e0 [com20020_pci] [ 3.975181] Call Trace: [ 3.976208] local_pci_probe+0x13f/0x210 [ 3.977248] pci_device_probe+0x34c/0x6d0 [ 3.977255] ? pci_uevent+0x470/0x470 [ 3.978265] really_probe+0x24c/0x8d0 [ 3.978273] __driver_probe_device+0x1b3/0x280 [ 3.979288] driver_probe_device+0x50/0x370

Fix this by checking whether the 'ci' is a null pointer first.