CyberRota Analysis
AI-GeneratedThe vulnerability affects the Linux kernel's handling of USB Type-C Power Delivery (PD) capabilities, specifically in the `cros_typec_register_partner_pdos()` function, which improperly copies data into a fixed-size array without adequate bounds checking. This oversight could lead to stack overflow if the source or sink capability counts exceed the maximum allowed, potentially allowing an attacker to execute arbitrary code or crash the system. Organizations using Linux or ChromeOS should prioritize addressing this issue to prevent exploitation, especially in environments where USB Type-C devices are frequently connected.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: platform/chrome: cros_ec_typec: Reject out-of-bounds PD cap count cros_typec_register_partner_pdos() copies the partner PDOs from the EC TYPEC_STATUS response into the fixed caps_desc.pdo[PDO_MAX_OBJECTS] array. memcpy(caps_desc.pdo, resp->source_cap_pdos, sizeof(u32) * resp->source_cap_count); ... memcpy(caps_desc.pdo, resp->sink_cap_pdos, sizeof(u32) * resp->sink_cap_count); PDO_MAX_OBJECTS is 7. source_cap_count and sink_cap_count are u8 fields from the EC. The only check is that they are not both zero. If either is larger than 7, the memcpy writes past the end of the array on the stack. A count of 255 overflows it by about 1 KB. The EC source arrays are only seven entries wide. A larger count reads past them too. The ChromeOS EC firmware caps these counts today, so a compliant setup does not hit this. The kernel should still validate these values rather than trust them. Validate the counts in cros_typec_register_partner_pdos() next to the memcpy. Skip the PDO registration if either count is above PDO_MAX_OBJECTS. The rest of cros_typec_handle_status() still runs so events are handled and cleared.