CVE-2026-46151

Description

In the Linux kernel, the following vulnerability has been resolved: usb: usblp: fix heap leak in IEEE 1284 device ID via short response usblp_ctrl_msg() collapses the usb_control_msg() return value to 0/-errno, discarding the actual number of bytes transferred. A broken printer can complete the GET_DEVICE_ID control transfer short and the driver has no way to know. usblp_cache_device_id_string() reads the 2-byte big-endian length prefix from the response and trusts it (clamped only to the buffer bounds). The buffer is kmalloc(1024) at probe time. A device that sends exactly two bytes (e.g. 0x03 0xFF, claiming a 1023-byte ID) leaves device_id_string[2..1022] holding stale kmalloc heap. That stale data is then exposed: - via the ieee1284_id sysfs attribute (sprintf(-%s-, buf+2), truncated at the first NUL in the stale heap), and - via the IOCNR_GET_DEVICE_ID ioctl, which copy_to_user()s the full claimed length regardless of NULs, up to 1021 bytes of uninitialized heap, with the leak size...