Buffer underflow in the ibwdt_ioctl function in drivers/watchdog/ib700wdt.c in the Linux kernel before 2.6.28-rc1 might allow local users to have an unknown impact via a certain /dev/watchdog WDIOC_SETTIMEOUT IOCTL call.
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.