CVE-2021-47503 scsi: pm80xx: Do not call scsi_remove_host() in pm8001_alloc()

What is CVE-2021-47503?

CVE-2021-47503 is a medium-severity vulnerability in Linux kernel, published on 24 May 2024. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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

scsi: pm80xx: Do not call scsi_remove_host() in pm8001_alloc()

Calling scsi_remove_host() before scsi_add_host() results in a crash:

BUG: kernel NULL pointer dereference, address: 0000000000000108 RIP: 0010:device_del+0x63/0x440 Call Trace: device_unregister+0x17/0x60 scsi_remove_host+0xee/0x2a0 pm8001_pci_probe+0x6ef/0x1b90 [pm80xx] local_pci_probe+0x3f/0x90

We cannot call scsi_remove_host() in pm8001_alloc() because scsi_add_host() has not been called yet at that point in time.

Function call tree:

pm8001_pci_probe() | `- pm8001_pci_alloc() | | | `- pm8001_alloc() | | | `- scsi_remove_host() | `- scsi_add_host()

Weakness: CWE-476

Which versions are affected by CVE-2021-47503?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2021-47503?

Apply the vendor's patch.

Is CVE-2021-47503 being exploited?

There is no known exploitation of CVE-2021-47503 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• How this page is made

Also known as DEBIAN-CVE-2021-47503, UBUNTU-CVE-2021-47503.