Re: [RESEND PATCH v2] cxgbi: move cxgbi_ddp_set_one_ppod to cxgb_ppm and remove its duplicate

From: Dan Carpenter
Date: Thu Dec 29 2022 - 08:54:08 EST


Hi Daniil,

https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Daniil-Tatianin/cxgbi-move-cxgbi_ddp_set_one_ppod-to-cxgb_ppm-and-remove-its-duplicate/20221226-171028
base: https://git.kernel.org/pub/scm/linux/kernel/git/mkp/scsi.git for-next
patch link: https://lore.kernel.org/r/20221226090609.1917788-1-d-tatianin%40yandex-team.ru
patch subject: [RESEND PATCH v2] cxgbi: move cxgbi_ddp_set_one_ppod to cxgb_ppm and remove its duplicate
config: powerpc-randconfig-m031-20221226
compiler: powerpc-linux-gcc (GCC) 12.1.0

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Reported-by: Dan Carpenter <error27@xxxxxxxxx>

smatch warnings:
drivers/net/ethernet/chelsio/libcxgb/libcxgb_ppm.c:571 cxgbi_ppm_set_one_ppod() error: we previously assumed 'sg_off' could be null (see line 536)

vim +/sg_off +571 drivers/net/ethernet/chelsio/libcxgb/libcxgb_ppm.c

e775e542c914b4 Daniil Tatianin 2022-12-26 530 void
e775e542c914b4 Daniil Tatianin 2022-12-26 531 cxgbi_ppm_set_one_ppod(struct cxgbi_pagepod *ppod,
e775e542c914b4 Daniil Tatianin 2022-12-26 532 struct cxgbi_task_tag_info *ttinfo,
e775e542c914b4 Daniil Tatianin 2022-12-26 533 struct scatterlist **sg_pp, unsigned int *sg_off)
e775e542c914b4 Daniil Tatianin 2022-12-26 534 {
e775e542c914b4 Daniil Tatianin 2022-12-26 535 struct scatterlist *sg = sg_pp ? *sg_pp : NULL;
e775e542c914b4 Daniil Tatianin 2022-12-26 @536 unsigned int offset = sg_off ? *sg_off : 0;
^^^^^^
Check for NULL

e775e542c914b4 Daniil Tatianin 2022-12-26 537 dma_addr_t addr = 0UL;
e775e542c914b4 Daniil Tatianin 2022-12-26 538 unsigned int len = 0;
e775e542c914b4 Daniil Tatianin 2022-12-26 539 int i;
e775e542c914b4 Daniil Tatianin 2022-12-26 540
e775e542c914b4 Daniil Tatianin 2022-12-26 541 memcpy(ppod, &ttinfo->hdr, sizeof(struct cxgbi_pagepod_hdr));
e775e542c914b4 Daniil Tatianin 2022-12-26 542
e775e542c914b4 Daniil Tatianin 2022-12-26 543 if (sg) {
e775e542c914b4 Daniil Tatianin 2022-12-26 544 addr = sg_dma_address(sg);
e775e542c914b4 Daniil Tatianin 2022-12-26 545 len = sg_dma_len(sg);
e775e542c914b4 Daniil Tatianin 2022-12-26 546 }
e775e542c914b4 Daniil Tatianin 2022-12-26 547
e775e542c914b4 Daniil Tatianin 2022-12-26 548 for (i = 0; i < PPOD_PAGES_MAX; i++) {
e775e542c914b4 Daniil Tatianin 2022-12-26 549 if (sg) {
e775e542c914b4 Daniil Tatianin 2022-12-26 550 ppod->addr[i] = cpu_to_be64(addr + offset);
e775e542c914b4 Daniil Tatianin 2022-12-26 551 offset += PAGE_SIZE;
e775e542c914b4 Daniil Tatianin 2022-12-26 552 if (offset == (len + sg->offset)) {
e775e542c914b4 Daniil Tatianin 2022-12-26 553 offset = 0;
e775e542c914b4 Daniil Tatianin 2022-12-26 554 sg = sg_next(sg);
e775e542c914b4 Daniil Tatianin 2022-12-26 555 if (sg) {
e775e542c914b4 Daniil Tatianin 2022-12-26 556 addr = sg_dma_address(sg);
e775e542c914b4 Daniil Tatianin 2022-12-26 557 len = sg_dma_len(sg);
e775e542c914b4 Daniil Tatianin 2022-12-26 558 }
e775e542c914b4 Daniil Tatianin 2022-12-26 559 }
e775e542c914b4 Daniil Tatianin 2022-12-26 560 } else {
e775e542c914b4 Daniil Tatianin 2022-12-26 561 ppod->addr[i] = 0ULL;
e775e542c914b4 Daniil Tatianin 2022-12-26 562 }
e775e542c914b4 Daniil Tatianin 2022-12-26 563 }
e775e542c914b4 Daniil Tatianin 2022-12-26 564
e775e542c914b4 Daniil Tatianin 2022-12-26 565 /*
e775e542c914b4 Daniil Tatianin 2022-12-26 566 * the fifth address needs to be repeated in the next ppod, so do
e775e542c914b4 Daniil Tatianin 2022-12-26 567 * not move sg
e775e542c914b4 Daniil Tatianin 2022-12-26 568 */
e775e542c914b4 Daniil Tatianin 2022-12-26 569 if (sg_pp) {
e775e542c914b4 Daniil Tatianin 2022-12-26 570 *sg_pp = sg;
e775e542c914b4 Daniil Tatianin 2022-12-26 @571 *sg_off = offset;
^^^^^^^
Unchecked dereference.

e775e542c914b4 Daniil Tatianin 2022-12-26 572 }
e775e542c914b4 Daniil Tatianin 2022-12-26 573
e775e542c914b4 Daniil Tatianin 2022-12-26 574 if (offset == len) {
e775e542c914b4 Daniil Tatianin 2022-12-26 575 offset = 0;
e775e542c914b4 Daniil Tatianin 2022-12-26 576 if (sg) {
e775e542c914b4 Daniil Tatianin 2022-12-26 577 sg = sg_next(sg);
e775e542c914b4 Daniil Tatianin 2022-12-26 578 if (sg)
e775e542c914b4 Daniil Tatianin 2022-12-26 579 addr = sg_dma_address(sg);
e775e542c914b4 Daniil Tatianin 2022-12-26 580 }
e775e542c914b4 Daniil Tatianin 2022-12-26 581 }
e775e542c914b4 Daniil Tatianin 2022-12-26 582 ppod->addr[i] = sg ? cpu_to_be64(addr + offset) : 0ULL;
e775e542c914b4 Daniil Tatianin 2022-12-26 583 }

--
0-DAY CI Kernel Test Service
https://01.org/lkp