[ammarfaizi2-block:rostedt/linux-trace/for-next 25/32] kernel/trace/trace_events_user.c:593:31: sparse: sparse: incorrect type in assignment (different address spaces)

From: kernel test robot
Date: Mon Feb 21 2022 - 07:47:23 EST

tree: https://github.com/ammarfaizi2/linux-block rostedt/linux-trace/for-next
head: 864ea0e10cc90416a01b46f0d47a6f26dc020820
commit: 0279400ad38d858ed68f5d787385f6122d4170b2 [25/32] user_events: Optimize writing events by only copying data once
config: x86_64-randconfig-s032-20220221 (https://download.01.org/0day-ci/archive/20220221/202202212008.H48tBYrJ-lkp@xxxxxxxxx/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce:
# apt-get install sparse
# sparse version: v0.6.4-dirty
# https://github.com/ammarfaizi2/linux-block/commit/0279400ad38d858ed68f5d787385f6122d4170b2
git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block
git fetch --no-tags ammarfaizi2-block rostedt/linux-trace/for-next
git checkout 0279400ad38d858ed68f5d787385f6122d4170b2
# save the config file to linux build tree
mkdir build_dir
make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=x86_64 SHELL=/bin/bash kernel/trace/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>


sparse warnings: (new ones prefixed by >>)
kernel/trace/trace_events_user.c:409:38: sparse: sparse: Using plain integer as NULL pointer
kernel/trace/trace_events_user.c:430:40: sparse: sparse: Using plain integer as NULL pointer
>> kernel/trace/trace_events_user.c:593:31: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected void *[assigned] udata @@ got void [noderef] __user * @@
kernel/trace/trace_events_user.c:593:31: sparse: expected void *[assigned] udata
kernel/trace/trace_events_user.c:593:31: sparse: got void [noderef] __user *
kernel/trace/trace_events_user.c:1064:16: sparse: sparse: incompatible types in comparison expression (different address spaces):
kernel/trace/trace_events_user.c:1064:16: sparse: void [noderef] __rcu *
kernel/trace/trace_events_user.c:1064:16: sparse: void *
kernel/trace/trace_events_user.c:1122:13: sparse: sparse: cast removes address space '__user' of expression
kernel/trace/trace_events_user.c:1122:13: sparse: sparse: incorrect type in argument 2 (different address spaces) @@ expected void [noderef] __user *buf @@ got char * @@
kernel/trace/trace_events_user.c:1122:13: sparse: expected void [noderef] __user *buf
kernel/trace/trace_events_user.c:1122:13: sparse: got char *
kernel/trace/trace_events_user.c:1138:16: sparse: sparse: incompatible types in comparison expression (different address spaces):
kernel/trace/trace_events_user.c:1138:16: sparse: void [noderef] __rcu *
kernel/trace/trace_events_user.c:1138:16: sparse: void *
kernel/trace/trace_events_user.c:1165:9: sparse: sparse: incompatible types in comparison expression (different address spaces):
kernel/trace/trace_events_user.c:1165:9: sparse: void [noderef] __rcu *
kernel/trace/trace_events_user.c:1165:9: sparse: void *

vim +593 kernel/trace/trace_events_user.c

378
379 static const char *user_field_format(const char *type)
380 {
381 if (strcmp(type, "s64") == 0)
382 return "%lld";
383 if (strcmp(type, "u64") == 0)
384 return "%llu";
385 if (strcmp(type, "s32") == 0)
386 return "%d";
387 if (strcmp(type, "u32") == 0)
388 return "%u";
389 if (strcmp(type, "int") == 0)
390 return "%d";
391 if (strcmp(type, "unsigned int") == 0)
392 return "%u";
393 if (strcmp(type, "s16") == 0)
394 return "%d";
395 if (strcmp(type, "u16") == 0)
396 return "%u";
397 if (strcmp(type, "short") == 0)
398 return "%d";
399 if (strcmp(type, "unsigned short") == 0)
400 return "%u";
401 if (strcmp(type, "s8") == 0)
402 return "%d";
403 if (strcmp(type, "u8") == 0)
404 return "%u";
405 if (strcmp(type, "char") == 0)
406 return "%d";
407 if (strcmp(type, "unsigned char") == 0)
408 return "%u";
> 409 if (strstr(type, "char[") != 0)
410 return "%s";
411
412 /* Unknown, likely struct, allowed treat as 64-bit */
413 return "%llu";
414 }
415
416 static bool user_field_is_dyn_string(const char *type, const char **str_func)
417 {
418 if (str_has_prefix(type, "__data_loc ")) {
419 *str_func = "__get_str";
420 goto check;
421 }
422
423 if (str_has_prefix(type, "__rel_loc ")) {
424 *str_func = "__get_rel_str";
425 goto check;
426 }
427
428 return false;
429 check:
430 return strstr(type, "char") != 0;
431 }
432
433 #define LEN_OR_ZERO (len ? len - pos : 0)
434 static int user_event_set_print_fmt(struct user_event *user, char *buf, int len)
435 {
436 struct ftrace_event_field *field, *next;
437 struct list_head *head = &user->fields;
438 int pos = 0, depth = 0;
439 const char *str_func;
440
441 pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
442
443 list_for_each_entry_safe_reverse(field, next, head, link) {
444 if (depth != 0)
445 pos += snprintf(buf + pos, LEN_OR_ZERO, " ");
446
447 pos += snprintf(buf + pos, LEN_OR_ZERO, "%s=%s",
448 field->name, user_field_format(field->type));
449
450 depth++;
451 }
452
453 pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
454
455 list_for_each_entry_safe_reverse(field, next, head, link) {
456 if (user_field_is_dyn_string(field->type, &str_func))
457 pos += snprintf(buf + pos, LEN_OR_ZERO,
458 ", %s(%s)", str_func, field->name);
459 else
460 pos += snprintf(buf + pos, LEN_OR_ZERO,
461 ", REC->%s", field->name);
462 }
463
464 return pos + 1;
465 }
466 #undef LEN_OR_ZERO
467
468 static int user_event_create_print_fmt(struct user_event *user)
469 {
470 char *print_fmt;
471 int len;
472
473 len = user_event_set_print_fmt(user, NULL, 0);
474
475 print_fmt = kmalloc(len, GFP_KERNEL);
476
477 if (!print_fmt)
478 return -ENOMEM;
479
480 user_event_set_print_fmt(user, print_fmt, len);
481
482 user->call.print_fmt = print_fmt;
483
484 return 0;
485 }
486
487 static enum print_line_t user_event_print_trace(struct trace_iterator *iter,
488 int flags,
489 struct trace_event *event)
490 {
491 /* Unsafe to try to decode user provided print_fmt, use hex */
492 trace_print_hex_dump_seq(&iter->seq, "", DUMP_PREFIX_OFFSET, 16,
493 1, iter->ent, iter->ent_size, true);
494
495 return trace_handle_return(&iter->seq);
496 }
497
498 static struct trace_event_functions user_event_funcs = {
499 .trace = user_event_print_trace,
500 };
501
502 static int destroy_user_event(struct user_event *user)
503 {
504 int ret = 0;
505
506 /* Must destroy fields before call removal */
507 user_event_destroy_fields(user);
508
509 ret = trace_remove_event_call(&user->call);
510
511 if (ret)
512 return ret;
513
514 dyn_event_remove(&user->devent);
515
516 register_page_data[user->index] = 0;
517 clear_bit(user->index, page_bitmap);
518 hash_del(&user->node);
519
520 kfree(user->call.print_fmt);
521 kfree(EVENT_NAME(user));
522 kfree(user);
523
524 return ret;
525 }
526
527 static struct user_event *find_user_event(char *name, u32 *outkey)
528 {
529 struct user_event *user;
530 u32 key = user_event_key(name);
531
532 *outkey = key;
533
534 hash_for_each_possible(register_table, user, node, key)
535 if (!strcmp(EVENT_NAME(user), name))
536 return user;
537
538 return NULL;
539 }
540
541 /*
542 * Writes the user supplied payload out to a trace file.
543 */
544 static void user_event_ftrace(struct user_event *user, struct iov_iter *i,
545 void *tpdata)
546 {
547 struct trace_event_file *file;
548 struct trace_entry *entry;
549 struct trace_event_buffer event_buffer;
550
551 file = (struct trace_event_file *)tpdata;
552
553 if (!file ||
554 !(file->flags & EVENT_FILE_FL_ENABLED) ||
555 trace_trigger_soft_disabled(file))
556 return;
557
558 /* Allocates and fills trace_entry, + 1 of this is data payload */
559 entry = trace_event_buffer_reserve(&event_buffer, file,
560 sizeof(*entry) + i->count);
561
562 if (unlikely(!entry))
563 return;
564
565 if (unlikely(!copy_nofault(entry + 1, i->count, i)))
566 __trace_event_discard_commit(event_buffer.buffer,
567 event_buffer.event);
568 else
569 trace_event_buffer_commit(&event_buffer);
570 }
571
572 #ifdef CONFIG_PERF_EVENTS
573 static void user_event_bpf(struct user_event *user, struct iov_iter *i)
574 {
575 struct user_bpf_context context;
576 struct user_bpf_iter bpf_i;
577 char fast_data[MAX_STACK_BPF_DATA];
578 void *temp = NULL;
579
580 if ((user->flags & FLAG_BPF_ITER) && iter_is_iovec(i)) {
581 /* Raw iterator */
582 context.data_type = USER_BPF_DATA_ITER;
583 context.data_len = i->count;
584 context.iter = &bpf_i;
585
586 bpf_i.iov_offset = i->iov_offset;
587 bpf_i.iov = i->iov;
588 bpf_i.nr_segs = i->nr_segs;
589 } else if (i->nr_segs == 1 && iter_is_iovec(i)) {
590 /* Single buffer from user */
591 context.data_type = USER_BPF_DATA_USER;
592 context.data_len = i->count;
> 593 context.udata = i->iov->iov_base + i->iov_offset;
594 } else {
595 /* Multi buffer from user */
596 struct iov_iter copy = *i;
597 size_t copy_size = min_t(size_t, i->count, MAX_BPF_COPY_SIZE);
598
599 context.data_type = USER_BPF_DATA_KERNEL;
600 context.kdata = fast_data;
601
602 if (unlikely(copy_size > sizeof(fast_data))) {
603 temp = kmalloc(copy_size, GFP_NOWAIT);
604
605 if (temp)
606 context.kdata = temp;
607 else
608 copy_size = sizeof(fast_data);
609 }
610
611 context.data_len = copy_nofault(context.kdata,
612 copy_size, &copy);
613 }
614
615 trace_call_bpf(&user->call, &context);
616
617 kfree(temp);
618 }
619

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx