Re: [PATCH] spi: spi-topcliff-pch: Fixed the possible null pointer exception issue
From: Dan Carpenter
Date: Fri Jun 25 2021 - 08:46:40 EST
Hi,
url: https://github.com/0day-ci/linux/commits/lijian_8010a29-163-com/spi-spi-topcliff-pch-Fixed-the-possible-null-pointer-exception-issue/20210624-185333
base: https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next
config: i386-randconfig-m021-20210622 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
New smatch warnings:
drivers/spi/spi-topcliff-pch.c:632 pch_spi_set_tx() error: uninitialized symbol 'j'.
Old smatch warnings:
drivers/spi/spi-topcliff-pch.c:1253 pch_spi_process_messages() warn: variable dereferenced before check 'data->cur_trans' (see line 1201)
vim +/j +632 drivers/spi/spi-topcliff-pch.c
c37f3c2749b5322 drivers/spi/spi-topcliff-pch.c Tomoya MORINAGA 2011-06-07 544 static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw)
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 545 {
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 546 int size;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 547 u32 n_writes;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 548 int j;
cd8d984f0def2a8 drivers/spi/spi-topcliff-pch.c Wei Yongjun 2013-04-27 549 struct spi_message *pmsg, *tmp;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 550 const u8 *tx_buf;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 551 const u16 *tx_sbuf;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 552
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 553 /* set baud rate if needed */
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 554 if (data->cur_trans->speed_hz) {
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 555 dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 556 pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 557 }
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 558
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 559 /* set bits per word if needed */
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 560 if (data->cur_trans->bits_per_word &&
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 561 (data->current_msg->spi->bits_per_word != data->cur_trans->bits_per_word)) {
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 562 dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 563 pch_spi_set_bits_per_word(data->master,
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 564 data->cur_trans->bits_per_word);
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 565 *bpw = data->cur_trans->bits_per_word;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 566 } else {
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 567 *bpw = data->current_msg->spi->bits_per_word;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 568 }
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 569
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 570 /* reset Tx/Rx index */
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 571 data->tx_index = 0;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 572 data->rx_index = 0;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 573
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 574 data->bpw_len = data->cur_trans->len / (*bpw / 8);
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 575
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 576 /* find alloc size */
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 577 size = data->cur_trans->len * sizeof(*data->pkt_tx_buff);
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 578
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 579 /* allocate memory for pkt_tx_buff & pkt_rx_buffer */
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 580 data->pkt_tx_buff = kzalloc(size, GFP_KERNEL);
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 581 if (data->pkt_tx_buff != NULL) {
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 582 data->pkt_rx_buff = kzalloc(size, GFP_KERNEL);
026a1dc1af52742 drivers/spi/spi-topcliff-pch.c Jay Fang 2021-05-06 583 if (!data->pkt_rx_buff) {
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 584 kfree(data->pkt_tx_buff);
026a1dc1af52742 drivers/spi/spi-topcliff-pch.c Jay Fang 2021-05-06 585 data->pkt_tx_buff = NULL;
026a1dc1af52742 drivers/spi/spi-topcliff-pch.c Jay Fang 2021-05-06 586 }
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 587 }
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 588
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 589 if (!data->pkt_rx_buff) {
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 590 /* flush queue and set status of all transfers to -ENOMEM */
cd8d984f0def2a8 drivers/spi/spi-topcliff-pch.c Wei Yongjun 2013-04-27 591 list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 592 pmsg->status = -ENOMEM;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 593
f5d8ee3f15dd718 drivers/spi/spi-topcliff-pch.c Sachin Kamat 2013-05-31 594 if (pmsg->complete)
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 595 pmsg->complete(pmsg->context);
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 596
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 597 /* delete from queue */
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 598 list_del_init(&pmsg->queue);
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 599 }
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 600 return;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 601 }
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 602
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 603 /* copy Tx Data */
393b49835a2b7cf drivers/spi/spi-topcliff-pch.c lijian 2021-06-24 604 if ((data->cur_trans->tx_buf != NULL) && (data->pkt_tx_buff != NULL)) {
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 605 if (*bpw == 8) {
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 606 tx_buf = data->cur_trans->tx_buf;
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 607 for (j = 0; j < data->bpw_len; j++)
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 608 data->pkt_tx_buff[j] = *tx_buf++;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 609 } else {
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 610 tx_sbuf = data->cur_trans->tx_buf;
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 611 for (j = 0; j < data->bpw_len; j++)
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 612 data->pkt_tx_buff[j] = *tx_sbuf++;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 613 }
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 614 }
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 615
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 616 /* if len greater than PCH_MAX_FIFO_DEPTH, write 16,else len bytes */
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 617 n_writes = data->bpw_len;
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 618 if (n_writes > PCH_MAX_FIFO_DEPTH)
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 619 n_writes = PCH_MAX_FIFO_DEPTH;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 620
b996356d305fd31 drivers/spi/spi-topcliff-pch.c Markus Elfring 2017-01-13 621 dev_dbg(&data->master->dev,
b996356d305fd31 drivers/spi/spi-topcliff-pch.c Markus Elfring 2017-01-13 622 "\n%s:Pulling down SSN low - writing 0x2 to SSNXCR\n",
b996356d305fd31 drivers/spi/spi-topcliff-pch.c Markus Elfring 2017-01-13 623 __func__);
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 624 pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 625
393b49835a2b7cf drivers/spi/spi-topcliff-pch.c lijian 2021-06-24 626 if (data->pkt_tx_buff != NULL) {
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 627 for (j = 0; j < n_writes; j++)
65308c46b760bb2 drivers/spi/spi_topcliff_pch.c Grant Likely 2010-09-29 628 pch_spi_writereg(data->master, PCH_SPDWR, data->pkt_tx_buff[j]);
393b49835a2b7cf drivers/spi/spi-topcliff-pch.c lijian 2021-06-24 629 }
"j" not initialized on else path.
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 630
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 631 /* update tx_index */
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 @632 data->tx_index = j;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 633
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 634 /* reset transfer complete flag */
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 635 data->transfer_complete = false;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 636 data->transfer_active = true;
e8b17b5b3f30252 drivers/spi/spi_topcliff_pch.c Masayuki Ohtake 2010-10-08 637 }
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx