4:56 a.m.
tree: https://git.kernel.org/pub/scm/linux/kernel/git/mhiramat/linux.git
kprobes/kretprobe-stackfix
head: 6e2b8966c87adc1be0fb4a386fb24ae438f4cb79
commit: 3f16730e94371a16e7c5490095b089cb198440e6 [9/10] x86/unwind/orc,kprobes: Fixup
kretprobe trampoline entry
config: x86_64-randconfig-m001-20210316 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
#
https://git.kernel.org/pub/scm/linux/kernel/git/mhiramat/linux.git/commit...
git remote add mhiramat
https://git.kernel.org/pub/scm/linux/kernel/git/mhiramat/linux.git
git fetch --no-tags mhiramat kprobes/kretprobe-stackfix
git checkout 3f16730e94371a16e7c5490095b089cb198440e6
# save the attached .config to linux build tree
make W=1 ARCH=x86_64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp(a)intel.com>
All errors (new ones prefixed by >>):
arch/x86/kernel/unwind_orc.c: In function 'unwind_next_frame':
> arch/x86/kernel/unwind_orc.c:547:18: error: 'struct
unwind_state' has no member named 'kr_iter'
547 |
&state->kr_iter);
| ^~
vim +547 arch/x86/kernel/unwind_orc.c
417
418 bool unwind_next_frame(struct unwind_state *state)
419 {
420 unsigned long ip_p, sp, tmp, orig_ip = state->ip, prev_sp = state->sp;
421 enum stack_type prev_type = state->stack_info.type;
422 struct orc_entry *orc;
423 bool indirect = false;
424
425 if (unwind_done(state))
426 return false;
427
428 /* Don't let modules unload while we're reading their ORC data. */
429 preempt_disable();
430
431 /* End-of-stack check for user tasks: */
432 if (state->regs && user_mode(state->regs))
433 goto the_end;
434
435 /*
436 * Find the orc_entry associated with the text address.
437 *
438 * For a call frame (as opposed to a signal frame), state->ip points to
439 * the instruction after the call. That instruction's stack layout
440 * could be different from the call instruction's layout, for example
441 * if the call was to a noreturn function. So get the ORC data for the
442 * call instruction itself.
443 */
444 orc = orc_find(state->signal ? state->ip : state->ip - 1);
445 if (!orc) {
446 /*
447 * As a fallback, try to assume this code uses a frame pointer.
448 * This is useful for generated code, like BPF, which ORC
449 * doesn't know about. This is just a guess, so the rest of
450 * the unwind is no longer considered reliable.
451 */
452 orc = &orc_fp_entry;
453 state->error = true;
454 }
455
456 /* End-of-stack check for kernel threads: */
457 if (orc->sp_reg == ORC_REG_UNDEFINED) {
458 if (!orc->end)
459 goto err;
460
461 goto the_end;
462 }
463
464 /* Find the previous frame's stack: */
465 switch (orc->sp_reg) {
466 case ORC_REG_SP:
467 sp = state->sp + orc->sp_offset;
468 break;
469
470 case ORC_REG_BP:
471 sp = state->bp + orc->sp_offset;
472 break;
473
474 case ORC_REG_SP_INDIRECT:
475 sp = state->sp;
476 indirect = true;
477 break;
478
479 case ORC_REG_BP_INDIRECT:
480 sp = state->bp + orc->sp_offset;
481 indirect = true;
482 break;
483
484 case ORC_REG_R10:
485 if (!get_reg(state, offsetof(struct pt_regs, r10), &sp)) {
486 orc_warn_current("missing R10 value at %pB\n",
487 (void *)state->ip);
488 goto err;
489 }
490 break;
491
492 case ORC_REG_R13:
493 if (!get_reg(state, offsetof(struct pt_regs, r13), &sp)) {
494 orc_warn_current("missing R13 value at %pB\n",
495 (void *)state->ip);
496 goto err;
497 }
498 break;
499
500 case ORC_REG_DI:
501 if (!get_reg(state, offsetof(struct pt_regs, di), &sp)) {
502 orc_warn_current("missing RDI value at %pB\n",
503 (void *)state->ip);
504 goto err;
505 }
506 break;
507
508 case ORC_REG_DX:
509 if (!get_reg(state, offsetof(struct pt_regs, dx), &sp)) {
510 orc_warn_current("missing DX value at %pB\n",
511 (void *)state->ip);
512 goto err;
513 }
514 break;
515
516 default:
517 orc_warn("unknown SP base reg %d at %pB\n",
518 orc->sp_reg, (void *)state->ip);
519 goto err;
520 }
521
522 if (indirect) {
523 if (!deref_stack_reg(state, sp, &sp))
524 goto err;
525
526 if (orc->sp_reg == ORC_REG_SP_INDIRECT)
527 sp += orc->sp_offset;
528 }
529
530 /* Find IP, SP and possibly regs: */
531 switch (orc->type) {
532 case UNWIND_HINT_TYPE_CALL:
533 ip_p = sp - sizeof(long);
534
535 if (!deref_stack_reg(state, ip_p, &state->ip))
536 goto err;
537
538 state->ip = ftrace_graph_ret_addr(state->task, &state->graph_idx,
539 state->ip, (void *)ip_p);
540 /*
541 * When the unwinder finds the kretprobe_trampoline instead of
542 * the real return address on stack, find the correct return
543 * address from task->kretprobe_instances list.
544 */
545 if (is_kretprobe_trampoline(state->ip))
546 state->ip = kretprobe_find_ret_addr(state->task,
547 &state->kr_iter);
548
549 state->sp = sp;
550 state->regs = NULL;
551 state->prev_regs = NULL;
552 state->signal = false;
553 break;
554
555 case UNWIND_HINT_TYPE_REGS:
556 if (!deref_stack_regs(state, sp, &state->ip, &state->sp)) {
557 orc_warn_current("can't access registers at %pB\n",
558 (void *)orig_ip);
559 goto err;
560 }
561
562 state->regs = (struct pt_regs *)sp;
563 state->prev_regs = NULL;
564 state->full_regs = true;
565 state->signal = true;
566 break;
567
568 case UNWIND_HINT_TYPE_REGS_PARTIAL:
569 if (!deref_stack_iret_regs(state, sp, &state->ip, &state->sp)) {
570 orc_warn_current("can't access iret registers at %pB\n",
571 (void *)orig_ip);
572 goto err;
573 }
574
575 if (state->full_regs)
576 state->prev_regs = state->regs;
577 state->regs = (void *)sp - IRET_FRAME_OFFSET;
578 state->full_regs = false;
579 state->signal = true;
580 break;
581
582 default:
583 orc_warn("unknown .orc_unwind entry type %d at %pB\n",
584 orc->type, (void *)orig_ip);
585 goto err;
586 }
587
588 /* Find BP: */
589 switch (orc->bp_reg) {
590 case ORC_REG_UNDEFINED:
591 if (get_reg(state, offsetof(struct pt_regs, bp), &tmp))
592 state->bp = tmp;
593 break;
594
595 case ORC_REG_PREV_SP:
596 if (!deref_stack_reg(state, sp + orc->bp_offset, &state->bp))
597 goto err;
598 break;
599
600 case ORC_REG_BP:
601 if (!deref_stack_reg(state, state->bp + orc->bp_offset,
&state->bp))
602 goto err;
603 break;
604
605 default:
606 orc_warn("unknown BP base reg %d for ip %pB\n",
607 orc->bp_reg, (void *)orig_ip);
608 goto err;
609 }
610
611 /* Prevent a recursive loop due to bad ORC data: */
612 if (state->stack_info.type == prev_type &&
613 on_stack(&state->stack_info, (void *)state->sp, sizeof(long))
&&
614 state->sp <= prev_sp) {
615 orc_warn_current("stack going in the wrong direction? at %pB\n",
616 (void *)orig_ip);
617 goto err;
618 }
619
620 preempt_enable();
621 return true;
622
623 err:
624 state->error = true;
625
626 the_end:
627 preempt_enable();
628 state->stack_info.type = STACK_TYPE_UNKNOWN;
629 return false;
630 }
631 EXPORT_SYMBOL_GPL(unwind_next_frame);
632
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org