In the Linux kernel, the following vulnerability has been resolved: PCI/AER: Avoid NULL pointer dereference in aer_ratelimit() When platform firmware supplies error information to the OS, e.g., via the ACPI APEI GHES mechanism, it may identify an error source device that doesn't advertise an AER Capability and therefore dev->aer_info, which contains AER stats and ratelimiting data, is NULL. pci_dev_aer_stats_incr() already checks dev->aer_info for NULL, but aer_ratelimit() did not, leading to NULL pointer dereferences like this one from the URL below: {1}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 0 {1}[Hardware Error]: event severity: corrected {1}[Hardware Error]: device_id: 0000:00:00.0 {1}[Hardware Error]: vendor_id: 0x8086, device_id: 0x20