On Wed, Jul 22, 2026 at 09:54:43AM +0200, Florian Weimer wrote: > * Dmitry V. Levin: > > > On Fri, Jan 23, 2026 at 01:09:13PM +0530, Mukesh Kumar Chaurasiya wrote: > >> From: Mukesh Kumar Chaurasiya <[email protected]> > >> > >> Add a new field `exit_flags` in the pt_regs structure. This field will hold > >> the flags set during interrupt or syscall execution that are required > >> during > >> exit to user mode. > > > > Apparently, this change breaks PTRACE_GETREGS as the latter has no means > > to communicate the size of struct pt_regs being written to userspace. > > > > As result, the kernel with this patch will write to userpsace 32 more > > bytes than before, and unless the userspace is re-compiled with the latest > > ptrace.h, 32 bytes of userspace memory after struct pt_regs will be > > overwritten. > > > > This issue was detected by strace test suite, specifically, the test that > > checks whether the actual number of bytes written by > > ptrace(PTRACE_GETREGS) matches sizeof(struct pt_regs), and that test failed > > with runtime version v7.1 and headers version v7.2-rc1. > > I think this needs to be reverted because it breaks existing ptrace > users. This isn't like iptables, where kernel updates did mandate > specific versions of the userspace tools. > > Thanks, > Florian > Hey,
Thanks for reporting this. I was unaware that this would break userspace. I am working on a fix for this, I am trying to maintain this state somewhere else than pt_regs. That would make the userspace work without recompilation. Regards, Mukesh
