CVE-2025-38284

/// Technical description

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

wifi: rtw89: pci: configure manual DAC mode via PCI config API only

To support 36-bit DMA, configure chip proprietary bit via PCI config API

or chip DBI interface. However, the PCI device mmap isn't set yet and

the DBI is also inaccessible via mmap, so only if the bit can be accessible

via PCI config API, chip can support 36-bit DMA. Otherwise, fallback to

32-bit DMA.

With NULL mmap address, kernel throws trace:

BUG: unable to handle page fault for address: 0000000000001090

#PF: supervisor write access in kernel mode

#PF: error_code(0x0002) - not-present page

PGD 0 P4D 0

Oops: Oops: 0002 [#1] PREEMPT SMP PTI

CPU: 1 UID: 0 PID: 71 Comm: irq/26-pciehp Tainted: G OE 6.14.2-061402-generic #202504101348

Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE

RIP: 0010:rtw89_pci_ops_write16+0x12/0x30 [rtw89_pci]

RSP: 0018:ffffb0ffc0acf9d8 EFLAGS: 00010206

RAX: ffffffffc158f9c0 RBX: ffff94865e70202

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References