[t-kristo-pm:usi-5.16-rfc-v3-bpf 17/24] drivers/hid/hid-bpf.c:376:6: warning: variable 'parser' is used uninitialized whenever 'if' condition is true

From: kernel test robot
Date: Thu Dec 02 2021 - 06:19:06 EST

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tree: https://github.com/t-kristo/linux-pm usi-5.16-rfc-v3-bpf
head: d0f251812c57f49830816624bec858500e4e14c2
commit: e4c4cfe6fd7edf4bdd3bbd2e408759db9b02290e [17/24] HID: bpf: compile fix for bpf_hid_foreach_rdesc_item
config: x86_64-randconfig-a001-20211202 (https://download.01.org/0day-ci/archive/20211202/202112021938.1gSUOhoI-lkp@xxxxxxxxx/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 4b553297ef3ee4dc2119d5429adf3072e90fac38)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/t-kristo/linux-pm/commit/e4c4cfe6fd7edf4bdd3bbd2e408759db9b02290e
git remote add t-kristo-pm https://github.com/t-kristo/linux-pm
git fetch --no-tags t-kristo-pm usi-5.16-rfc-v3-bpf
git checkout e4c4cfe6fd7edf4bdd3bbd2e408759db9b02290e
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/hid/

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

All warnings (new ones prefixed by >>):

drivers/hid/hid-bpf.c:141:5: warning: no previous prototype for function 'hid_bpf_prog_detach' [-Wmissing-prototypes]
int hid_bpf_prog_detach(struct hid_device *hdev, struct bpf_prog *prog)
^
drivers/hid/hid-bpf.c:141:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
int hid_bpf_prog_detach(struct hid_device *hdev, struct bpf_prog *prog)
^
static
drivers/hid/hid-bpf.c:229:24: warning: no previous prototype for function 'hid_bpf_add_report' [-Wmissing-prototypes]
struct hid_bpf_report *hid_bpf_add_report(struct hid_bpf_parser_and_data *data,
^
drivers/hid/hid-bpf.c:229:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
struct hid_bpf_report *hid_bpf_add_report(struct hid_bpf_parser_and_data *data,
^
static
drivers/hid/hid-bpf.c:257:6: warning: no previous prototype for function 'hid_bpf_free_reports' [-Wmissing-prototypes]
void hid_bpf_free_reports(struct hid_bpf_parser_and_data *data)
^
drivers/hid/hid-bpf.c:257:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
void hid_bpf_free_reports(struct hid_bpf_parser_and_data *data)
^
static
drivers/hid/hid-bpf.c:321:7: warning: variable 'ret' is used uninitialized whenever switch case is taken [-Wsometimes-uninitialized]
case HID_MAIN_ITEM_TAG_END_COLLECTION:
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/uapi/linux/hid.h:96:42: note: expanded from macro 'HID_MAIN_ITEM_TAG_END_COLLECTION'
#define HID_MAIN_ITEM_TAG_END_COLLECTION 12
^~
drivers/hid/hid-bpf.c:338:9: note: uninitialized use occurs here
return ret;
^~~
drivers/hid/hid-bpf.c:318:7: warning: variable 'ret' is used uninitialized whenever switch case is taken [-Wsometimes-uninitialized]
case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/uapi/linux/hid.h:95:44: note: expanded from macro 'HID_MAIN_ITEM_TAG_BEGIN_COLLECTION'
#define HID_MAIN_ITEM_TAG_BEGIN_COLLECTION 10
^~
drivers/hid/hid-bpf.c:338:9: note: uninitialized use occurs here
return ret;
^~~
drivers/hid/hid-bpf.c:311:9: note: initialize the variable 'ret' to silence this warning
int ret;
^
= 0
>> drivers/hid/hid-bpf.c:376:6: warning: variable 'parser' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
if (!parser_and_data) {
^~~~~~~~~~~~~~~~
drivers/hid/hid-bpf.c:427:8: note: uninitialized use occurs here
kfree(parser->collection_stack);
^~~~~~
drivers/hid/hid-bpf.c:376:2: note: remove the 'if' if its condition is always false
if (!parser_and_data) {
^~~~~~~~~~~~~~~~~~~~~~~
drivers/hid/hid-bpf.c:355:27: note: initialize the variable 'parser' to silence this warning
struct hid_parser *parser;
^
= NULL
6 warnings generated.

vim +376 drivers/hid/hid-bpf.c

db3fbbad76f8105 Benjamin Tissoires 2021-10-13 350
e4c4cfe6fd7edf4 Tero Kristo 2021-11-25 351 BPF_CALL_4(bpf_hid_foreach_rdesc_item, void*, ctx, bpf_callback_t, callback_fn, void *, callback_ctx, u64, flags)
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 352 {
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 353 struct hid_bpf_ctx *bpf_ctx = ctx;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 354 struct hid_bpf_parser_and_data *parser_and_data;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 355 struct hid_parser *parser;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 356 struct hid_bpf_parser *callback_data;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 357 struct hid_item item;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 358 u8 *data_copy, *start, *end, *next;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 359 u64 cur_index;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 360 u64 ret = 0;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 361 u32 num_elems = 0;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 362
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 363 static int (*dispatch_type[])(struct hid_parser *parser,
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 364 struct hid_item *item) = {
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 365 hid_bpf_parser_main,
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 366 hid_parser_global,
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 367 hid_parser_local,
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 368 hid_parser_reserved
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 369 };
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 370
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 371
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 372 if (flags != 0)
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 373 return -EINVAL;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 374
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 375 parser_and_data = vzalloc(sizeof(*parser_and_data));
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 @376 if (!parser_and_data) {
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 377 ret = -ENOMEM;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 378 goto exit;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 379 }
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 380
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 381 parser = &parser_and_data->parser;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 382 callback_data = &parser_and_data->callback_data;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 383
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 384 parser->device = bpf_ctx->hdev;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 385
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 386 data_copy = kmemdup(bpf_ctx->event.data, HID_BPF_MAX_BUFFER_SIZE, GFP_KERNEL);
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 387 if (!data_copy) {
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 388 ret = -ENOMEM;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 389 goto exit;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 390 }
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 391
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 392 start = data_copy;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 393 end = start + bpf_ctx->event.size;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 394
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 395 while((next = hid_rdesc_fetch_item(start, end, &item)) != NULL) {
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 396 cur_index = start - data_copy;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 397 num_elems++;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 398
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 399 dispatch_type[item.type](parser, &item);
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 400
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 401 hid_bpf_store_bpf_parser(callback_data, &item, parser);
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 402
e4c4cfe6fd7edf4 Tero Kristo 2021-11-25 403 ret = callback_fn((u64)(long)ctx, (u64)(long)callback_data,
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 404 (u64)(long)&cur_index,
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 405 (u64)(long)callback_ctx, 0);
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 406 /* return value: 0 - continue, 1 - stop and return */
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 407 if (ret)
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 408 break;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 409
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 410 /* Reset the local parser environment on main items */
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 411 if (item.type == HID_ITEM_TYPE_MAIN)
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 412 memset(&parser->local, 0, sizeof(parser->local));
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 413
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 414 /* clear item content */
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 415 memset(&item, 0, sizeof(item));
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 416
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 417 start = next;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 418 }
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 419
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 420 hid_bpf_free_reports(parser_and_data);
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 421
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 422 kfree(data_copy);
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 423
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 424 ret = num_elems;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 425
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 426 exit:
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 427 kfree(parser->collection_stack);
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 428 vfree(parser_and_data);
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 429 return ret;
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 430 }
db3fbbad76f8105 Benjamin Tissoires 2021-10-13 431

:::::: The code at line 376 was first introduced by commit
:::::: db3fbbad76f810554bcb2c098f8c9beb02724702 HID: bpf: add a helper to parse a given report descriptor

:::::: TO: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
:::::: CC: Tero Kristo <tero.kristo@xxxxxxxxxxxxxxx>

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

Next message: Qais Yousef: "[PATCH v2] sched/uclamp: Fix rq->uclamp_max not set on first enqueue"
Previous message: DTB Bank of Tanzania: "DTB Bank of Tanzania,"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]