CyberRota Analysis
AI-GeneratedThe vulnerability in the Linux kernel affects the ACPI subsystem, specifically in the `query_capability()` function, which improperly handles buffer lengths when copying firmware data into fixed-size structures. This flaw can lead to stack buffer overflows, potentially allowing an attacker to overwrite adjacent memory, which may result in system crashes or arbitrary code execution. Organizations using affected Linux kernel versions, especially those relying on ACPI for hardware management, should prioritize patching this vulnerability to mitigate potential exploitation risks.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: ACPI: pfr_update: fix stack buffer overflow in query_capability() query_capability() copies four ACPI buffer objects returned by the firmware _DSM into fixed-size u8[16] fields in struct pfru_update_cap_info using memcpy with the firmware-supplied length: memcpy(&cap_hdr->code_type, elements[CAP_CODE_TYPE_IDX].buffer.pointer, elements[CAP_CODE_TYPE_IDX].buffer.length); The same pattern repeats for drv_type, platform_id, and oem_id. If the firmware returns buffer.length > 16 for any of these fields, memcpy writes past the destination array. struct pfru_update_cap_info is stack-allocated in pfru_ioctl(). Confirmed with KASAN on 7.2-rc6: three stack-out-of-bounds reports are generated when a DSM returns 64-byte buffers, with writes reaching 44 bytes past the end of cap_hdr's [64, 156) frame window into adjacent stack redzones. Introduce a helper pointer to out_obj->package.elements and use it to validate each buffer length against its destination field size before copying, returning -EINVAL if the firmware supplies an oversized buffer.