Re: [PATCH -next] usb: gadget: dereference before null check

From: kernel test robot
Date: Wed Jun 29 2022 - 13:57:32 EST


Hi SebinSebastian,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on next-20220628]

url: https://github.com/intel-lab-lkp/linux/commits/SebinSebastian/usb-gadget-dereference-before-null-check/20220629-161008
base: cb71b93c2dc36d18a8b05245973328d018272cdf
config: mips-allyesconfig (https://download.01.org/0day-ci/archive/20220630/202206300156.qNpjgo9z-lkp@xxxxxxxxx/config)
compiler: mips-linux-gcc (GCC) 11.3.0
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/intel-lab-lkp/linux/commit/97ebbd93f269a58b3b5a003898d6e09c29a73ab0
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review SebinSebastian/usb-gadget-dereference-before-null-check/20220629-161008
git checkout 97ebbd93f269a58b3b5a003898d6e09c29a73ab0
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash

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

All errors (new ones prefixed by >>):

drivers/usb/gadget/udc/aspeed_udc.c: In function 'ast_udc_ep_enable':
>> drivers/usb/gadget/udc/aspeed_udc.c:349:22: error: 'ep' undeclared (first use in this function); did you mean '_ep'?
349 | if (!_ep || !ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT ||
| ^~
| _ep
drivers/usb/gadget/udc/aspeed_udc.c:349:22: note: each undeclared identifier is reported only once for each function it appears in
>> drivers/usb/gadget/udc/aspeed_udc.c:350:13: error: 'maxpacket' undeclared (first use in this function)
350 | maxpacket == 0 || maxpacket > ep->ep.maxpacket) {
| ^~~~~~~~~
drivers/usb/gadget/udc/aspeed_udc.c:355:9: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
355 | u16 maxpacket = usb_endpoint_maxp(desc);
| ^~~


vim +349 drivers/usb/gadget/udc/aspeed_udc.c

055276c1320564b Neal Liu 2022-05-23 340
055276c1320564b Neal Liu 2022-05-23 341 static int ast_udc_ep_enable(struct usb_ep *_ep,
055276c1320564b Neal Liu 2022-05-23 342 const struct usb_endpoint_descriptor *desc)
055276c1320564b Neal Liu 2022-05-23 343 {
055276c1320564b Neal Liu 2022-05-23 344 unsigned long flags;
055276c1320564b Neal Liu 2022-05-23 345 u32 ep_conf = 0;
055276c1320564b Neal Liu 2022-05-23 346 u8 dir_in;
055276c1320564b Neal Liu 2022-05-23 347 u8 type;
055276c1320564b Neal Liu 2022-05-23 348
055276c1320564b Neal Liu 2022-05-23 @349 if (!_ep || !ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT ||
055276c1320564b Neal Liu 2022-05-23 @350 maxpacket == 0 || maxpacket > ep->ep.maxpacket) {
055276c1320564b Neal Liu 2022-05-23 351 EP_DBG(ep, "Failed, invalid EP enable param\n");
055276c1320564b Neal Liu 2022-05-23 352 return -EINVAL;
055276c1320564b Neal Liu 2022-05-23 353 }
055276c1320564b Neal Liu 2022-05-23 354
97ebbd93f269a58 SebinSebastian 2022-06-29 355 u16 maxpacket = usb_endpoint_maxp(desc);
97ebbd93f269a58 SebinSebastian 2022-06-29 356 struct ast_udc_ep *ep = to_ast_ep(_ep);
97ebbd93f269a58 SebinSebastian 2022-06-29 357 struct ast_udc_dev *udc = ep->udc;
97ebbd93f269a58 SebinSebastian 2022-06-29 358 u8 epnum = usb_endpoint_num(desc);
97ebbd93f269a58 SebinSebastian 2022-06-29 359
055276c1320564b Neal Liu 2022-05-23 360 if (!udc->driver) {
055276c1320564b Neal Liu 2022-05-23 361 EP_DBG(ep, "bogus device state\n");
055276c1320564b Neal Liu 2022-05-23 362 return -ESHUTDOWN;
055276c1320564b Neal Liu 2022-05-23 363 }
055276c1320564b Neal Liu 2022-05-23 364
055276c1320564b Neal Liu 2022-05-23 365 EP_DBG(ep, "maxpacket:0x%x\n", maxpacket);
055276c1320564b Neal Liu 2022-05-23 366
055276c1320564b Neal Liu 2022-05-23 367 spin_lock_irqsave(&udc->lock, flags);
055276c1320564b Neal Liu 2022-05-23 368
055276c1320564b Neal Liu 2022-05-23 369 ep->desc = desc;
055276c1320564b Neal Liu 2022-05-23 370 ep->stopped = 0;
055276c1320564b Neal Liu 2022-05-23 371 ep->ep.maxpacket = maxpacket;
055276c1320564b Neal Liu 2022-05-23 372 ep->chunk_max = AST_EP_DMA_DESC_MAX_LEN;
055276c1320564b Neal Liu 2022-05-23 373
055276c1320564b Neal Liu 2022-05-23 374 if (maxpacket < AST_UDC_EPn_MAX_PACKET)
055276c1320564b Neal Liu 2022-05-23 375 ep_conf = EP_SET_MAX_PKT(maxpacket);
055276c1320564b Neal Liu 2022-05-23 376
055276c1320564b Neal Liu 2022-05-23 377 ep_conf |= EP_SET_EP_NUM(epnum);
055276c1320564b Neal Liu 2022-05-23 378
055276c1320564b Neal Liu 2022-05-23 379 type = usb_endpoint_type(desc);
055276c1320564b Neal Liu 2022-05-23 380 dir_in = usb_endpoint_dir_in(desc);
055276c1320564b Neal Liu 2022-05-23 381 ep->dir_in = dir_in;
055276c1320564b Neal Liu 2022-05-23 382 if (!ep->dir_in)
055276c1320564b Neal Liu 2022-05-23 383 ep_conf |= EP_DIR_OUT;
055276c1320564b Neal Liu 2022-05-23 384
055276c1320564b Neal Liu 2022-05-23 385 EP_DBG(ep, "type %d, dir_in %d\n", type, dir_in);
055276c1320564b Neal Liu 2022-05-23 386 switch (type) {
055276c1320564b Neal Liu 2022-05-23 387 case USB_ENDPOINT_XFER_ISOC:
055276c1320564b Neal Liu 2022-05-23 388 ep_conf |= EP_SET_TYPE_MASK(EP_TYPE_ISO);
055276c1320564b Neal Liu 2022-05-23 389 break;
055276c1320564b Neal Liu 2022-05-23 390
055276c1320564b Neal Liu 2022-05-23 391 case USB_ENDPOINT_XFER_BULK:
055276c1320564b Neal Liu 2022-05-23 392 ep_conf |= EP_SET_TYPE_MASK(EP_TYPE_BULK);
055276c1320564b Neal Liu 2022-05-23 393 break;
055276c1320564b Neal Liu 2022-05-23 394
055276c1320564b Neal Liu 2022-05-23 395 case USB_ENDPOINT_XFER_INT:
055276c1320564b Neal Liu 2022-05-23 396 ep_conf |= EP_SET_TYPE_MASK(EP_TYPE_INT);
055276c1320564b Neal Liu 2022-05-23 397 break;
055276c1320564b Neal Liu 2022-05-23 398 }
055276c1320564b Neal Liu 2022-05-23 399
055276c1320564b Neal Liu 2022-05-23 400 ep->desc_mode = udc->desc_mode && ep->descs_dma && ep->dir_in;
055276c1320564b Neal Liu 2022-05-23 401 if (ep->desc_mode) {
055276c1320564b Neal Liu 2022-05-23 402 ast_ep_write(ep, EP_DMA_CTRL_RESET, AST_UDC_EP_DMA_CTRL);
055276c1320564b Neal Liu 2022-05-23 403 ast_ep_write(ep, 0, AST_UDC_EP_DMA_STS);
055276c1320564b Neal Liu 2022-05-23 404 ast_ep_write(ep, ep->descs_dma, AST_UDC_EP_DMA_BUFF);
055276c1320564b Neal Liu 2022-05-23 405
055276c1320564b Neal Liu 2022-05-23 406 /* Enable Long Descriptor Mode */
055276c1320564b Neal Liu 2022-05-23 407 ast_ep_write(ep, EP_DMA_CTRL_IN_LONG_MODE | EP_DMA_DESC_MODE,
055276c1320564b Neal Liu 2022-05-23 408 AST_UDC_EP_DMA_CTRL);
055276c1320564b Neal Liu 2022-05-23 409
055276c1320564b Neal Liu 2022-05-23 410 ep->descs_wptr = 0;
055276c1320564b Neal Liu 2022-05-23 411
055276c1320564b Neal Liu 2022-05-23 412 } else {
055276c1320564b Neal Liu 2022-05-23 413 ast_ep_write(ep, EP_DMA_CTRL_RESET, AST_UDC_EP_DMA_CTRL);
055276c1320564b Neal Liu 2022-05-23 414 ast_ep_write(ep, EP_DMA_SINGLE_STAGE, AST_UDC_EP_DMA_CTRL);
055276c1320564b Neal Liu 2022-05-23 415 ast_ep_write(ep, 0, AST_UDC_EP_DMA_STS);
055276c1320564b Neal Liu 2022-05-23 416 }
055276c1320564b Neal Liu 2022-05-23 417
055276c1320564b Neal Liu 2022-05-23 418 /* Cleanup data toggle just in case */
055276c1320564b Neal Liu 2022-05-23 419 ast_udc_write(udc, EP_TOGGLE_SET_EPNUM(epnum), AST_VHUB_EP_DATA);
055276c1320564b Neal Liu 2022-05-23 420
055276c1320564b Neal Liu 2022-05-23 421 /* Enable EP */
055276c1320564b Neal Liu 2022-05-23 422 ast_ep_write(ep, ep_conf | EP_ENABLE, AST_UDC_EP_CONFIG);
055276c1320564b Neal Liu 2022-05-23 423
055276c1320564b Neal Liu 2022-05-23 424 EP_DBG(ep, "ep_config: 0x%x\n", ast_ep_read(ep, AST_UDC_EP_CONFIG));
055276c1320564b Neal Liu 2022-05-23 425
055276c1320564b Neal Liu 2022-05-23 426 spin_unlock_irqrestore(&udc->lock, flags);
055276c1320564b Neal Liu 2022-05-23 427
055276c1320564b Neal Liu 2022-05-23 428 return 0;
055276c1320564b Neal Liu 2022-05-23 429 }
055276c1320564b Neal Liu 2022-05-23 430

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