In the Linux kernel, the following vulnerability has been resolved: scsi: qla1280: Fix kernel oops when debug level > 2 A null dereference or oops exception will eventually occur when qla1280.c driver is compiled with DEBUG_QLA1280 enabled and ql_debug_level > 2. I think its clear from the code that the intention here is sg_dma_len(s) not length of sg_next(s) when printing the debug info.