CVE-2021-47503

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> scsi: pm80xx: Do not call scsi_remove_host() in pm8001_alloc()<br /> <br /> Calling scsi_remove_host() before scsi_add_host() results in a crash:<br /> <br /> BUG: kernel NULL pointer dereference, address: 0000000000000108<br /> RIP: 0010:device_del+0x63/0x440<br /> Call Trace:<br /> device_unregister+0x17/0x60<br /> scsi_remove_host+0xee/0x2a0<br /> pm8001_pci_probe+0x6ef/0x1b90 [pm80xx]<br /> local_pci_probe+0x3f/0x90<br /> <br /> We cannot call scsi_remove_host() in pm8001_alloc() because scsi_add_host()<br /> has not been called yet at that point in time.<br /> <br /> Function call tree:<br /> <br /> pm8001_pci_probe()<br /> |<br /> `- pm8001_pci_alloc()<br /> | |<br /> | `- pm8001_alloc()<br /> | |<br /> | `- scsi_remove_host()<br /> |<br /> `- scsi_add_host()