----- On Jul 2, 2018, at 1:11 PM, Andy Lutomirski l...@amacapital.net wrote: > > But I think that the limited solution of changing > instruction_pointer_set() really is a sufficient > architecture-dependent change to fully solve your problem.
So let me recap with the changes I gather for 4.18 and 4.19: 4.18: * Change struct rseq_cs field types from LINUX_FIELD_u32_u64() to __u64 in uapi/linux/rseq.h, * Compare rseq->rseq_cs->abort_ip with TASK_SIZE before using it. Kill offending process if its value is over TASK_SIZE, * Explicitly check that padding of rseq->rseq_cs is zero on 32-bit kernels (#ifndef __LP64__). 4.19: * Introduce instruction_pointer_set() with input validation, use it when setting IP to abort_ip in rseq. This replaces the comparison of abort_ip with TASK_SIZE. Is that consistent with what you have in mind ? Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com
