LinuxLists.cc - drivers/net/can/usb/peak_usb/pcan_usb.c:523 pcan_usb_decode_error() error: we previously assumed 'cf' could be null (see line 503)

2021-12-03 14:10:44

Subject: drivers/net/can/usb/peak_usb/pcan_usb.c:523 pcan_usb_decode_error() error: we previously assumed 'cf' could be null (see line 503)

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 58e1100fdc5990b0cc0d4beaf2562a92e621ac7d
commit: c11dcee758302702a83c6e85e4c4c3d9af42d2b3 can: peak_usb: pcan_usb_decode_error(): upgrade handling of bus state changes
config: x86_64-randconfig-m001-20211202 (https://download.01.org/0day-ci/archive/20211202/[email protected]/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 <[email protected]>
Reported-by: Dan Carpenter <[email protected]>

smatch warnings:
drivers/net/can/usb/peak_usb/pcan_usb.c:523 pcan_usb_decode_error() error: we previously assumed 'cf' could be null (see line 503)

vim +/cf +523 drivers/net/can/usb/peak_usb/pcan_usb.c

46be265d338833 Stephane Grosjean 2012-03-02 450 static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n,
46be265d338833 Stephane Grosjean 2012-03-02 451 u8 status_len)
46be265d338833 Stephane Grosjean 2012-03-02 452 {
46be265d338833 Stephane Grosjean 2012-03-02 453 struct sk_buff *skb;
46be265d338833 Stephane Grosjean 2012-03-02 454 struct can_frame *cf;
c11dcee7583027 Stephane Grosjean 2021-07-15 455 enum can_state new_state = CAN_STATE_ERROR_ACTIVE;
46be265d338833 Stephane Grosjean 2012-03-02 456
46be265d338833 Stephane Grosjean 2012-03-02 457 /* ignore this error until 1st ts received */
46be265d338833 Stephane Grosjean 2012-03-02 458 if (n == PCAN_USB_ERROR_QOVR)
46be265d338833 Stephane Grosjean 2012-03-02 459 if (!mc->pdev->time_ref.tick_count)
46be265d338833 Stephane Grosjean 2012-03-02 460 return 0;
46be265d338833 Stephane Grosjean 2012-03-02 461
c11dcee7583027 Stephane Grosjean 2021-07-15 462 /* allocate an skb to store the error frame */
c11dcee7583027 Stephane Grosjean 2021-07-15 463 skb = alloc_can_err_skb(mc->netdev, &cf);
46be265d338833 Stephane Grosjean 2012-03-02 464
c11dcee7583027 Stephane Grosjean 2021-07-15 465 if (n & PCAN_USB_ERROR_RXQOVR) {
c11dcee7583027 Stephane Grosjean 2021-07-15 466 /* data overrun interrupt */
c11dcee7583027 Stephane Grosjean 2021-07-15 467 netdev_dbg(mc->netdev, "data overrun interrupt\n");
c11dcee7583027 Stephane Grosjean 2021-07-15 468 mc->netdev->stats.rx_over_errors++;
c11dcee7583027 Stephane Grosjean 2021-07-15 469 mc->netdev->stats.rx_errors++;
c11dcee7583027 Stephane Grosjean 2021-07-15 470 if (cf) {

Check for NULL

c11dcee7583027 Stephane Grosjean 2021-07-15 471 cf->can_id |= CAN_ERR_CRTL;
c11dcee7583027 Stephane Grosjean 2021-07-15 472 cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;
46be265d338833 Stephane Grosjean 2012-03-02 473 }
46be265d338833 Stephane Grosjean 2012-03-02 474 }
46be265d338833 Stephane Grosjean 2012-03-02 475
c11dcee7583027 Stephane Grosjean 2021-07-15 476 if (n & PCAN_USB_ERROR_TXQFULL)
c11dcee7583027 Stephane Grosjean 2021-07-15 477 netdev_dbg(mc->netdev, "device Tx queue full)\n");
c11dcee7583027 Stephane Grosjean 2021-07-15 478
46be265d338833 Stephane Grosjean 2012-03-02 479 if (n & PCAN_USB_ERROR_BUS_OFF) {
46be265d338833 Stephane Grosjean 2012-03-02 480 new_state = CAN_STATE_BUS_OFF;
c11dcee7583027 Stephane Grosjean 2021-07-15 481 } else if (n & PCAN_USB_ERROR_BUS_HEAVY) {
c11dcee7583027 Stephane Grosjean 2021-07-15 482 new_state = ((mc->pdev->bec.txerr >= 128) ||
c11dcee7583027 Stephane Grosjean 2021-07-15 483 (mc->pdev->bec.rxerr >= 128)) ?
c11dcee7583027 Stephane Grosjean 2021-07-15 484 CAN_STATE_ERROR_PASSIVE :
c11dcee7583027 Stephane Grosjean 2021-07-15 485 CAN_STATE_ERROR_WARNING;
c11dcee7583027 Stephane Grosjean 2021-07-15 486 } else {
c11dcee7583027 Stephane Grosjean 2021-07-15 487 new_state = CAN_STATE_ERROR_ACTIVE;
46be265d338833 Stephane Grosjean 2012-03-02 488 }
46be265d338833 Stephane Grosjean 2012-03-02 489
c11dcee7583027 Stephane Grosjean 2021-07-15 490 /* handle change of state */
c11dcee7583027 Stephane Grosjean 2021-07-15 491 if (new_state != mc->pdev->dev.can.state) {
c11dcee7583027 Stephane Grosjean 2021-07-15 492 enum can_state tx_state =
c11dcee7583027 Stephane Grosjean 2021-07-15 493 (mc->pdev->bec.txerr >= mc->pdev->bec.rxerr) ?
c11dcee7583027 Stephane Grosjean 2021-07-15 494 new_state : 0;
c11dcee7583027 Stephane Grosjean 2021-07-15 495 enum can_state rx_state =
c11dcee7583027 Stephane Grosjean 2021-07-15 496 (mc->pdev->bec.txerr <= mc->pdev->bec.rxerr) ?
c11dcee7583027 Stephane Grosjean 2021-07-15 497 new_state : 0;
46be265d338833 Stephane Grosjean 2012-03-02 498
c11dcee7583027 Stephane Grosjean 2021-07-15 499 can_change_state(mc->netdev, cf, tx_state, rx_state);
46be265d338833 Stephane Grosjean 2012-03-02 500
c11dcee7583027 Stephane Grosjean 2021-07-15 501 if (new_state == CAN_STATE_BUS_OFF) {
46be265d338833 Stephane Grosjean 2012-03-02 502 can_bus_off(mc->netdev);
c11dcee7583027 Stephane Grosjean 2021-07-15 @503 } else if (cf && (cf->can_id & CAN_ERR_CRTL)) {

Check for NULL

c11dcee7583027 Stephane Grosjean 2021-07-15 504 /* Supply TX/RX error counters in case of
c11dcee7583027 Stephane Grosjean 2021-07-15 505 * controller error.
c11dcee7583027 Stephane Grosjean 2021-07-15 506 */
ea8b33bde76c8f Stephane Grosjean 2019-12-06 507 cf->data[6] = mc->pdev->bec.txerr;
ea8b33bde76c8f Stephane Grosjean 2019-12-06 508 cf->data[7] = mc->pdev->bec.rxerr;
ea8b33bde76c8f Stephane Grosjean 2019-12-06 509 }
46be265d338833 Stephane Grosjean 2012-03-02 510 }
46be265d338833 Stephane Grosjean 2012-03-02 511
c11dcee7583027 Stephane Grosjean 2021-07-15 512 if (!skb)
c11dcee7583027 Stephane Grosjean 2021-07-15 513 return -ENOMEM;
46be265d338833 Stephane Grosjean 2012-03-02 514
46be265d338833 Stephane Grosjean 2012-03-02 515 if (status_len & PCAN_USB_STATUSLEN_TIMESTAMP) {
c9faaa09e2a133 Oliver Hartkopp 2012-11-21 516 struct skb_shared_hwtstamps *hwts = skb_hwtstamps(skb);
c9faaa09e2a133 Oliver Hartkopp 2012-11-21 517
d5888a1e75c799 Arnd Bergmann 2017-11-03 518 peak_usb_get_ts_time(&mc->pdev->time_ref, mc->ts16,
d5888a1e75c799 Arnd Bergmann 2017-11-03 519 &hwts->hwtstamp);
46be265d338833 Stephane Grosjean 2012-03-02 520 }
46be265d338833 Stephane Grosjean 2012-03-02 521
46be265d338833 Stephane Grosjean 2012-03-02 522 mc->netdev->stats.rx_packets++;
c7b74967799b1a Oliver Hartkopp 2020-11-20 @523 mc->netdev->stats.rx_bytes += cf->len;
^^^^^^^^
No check for NULL.

1c0ee046957648 Marc Kleine-Budde 2015-07-11 524 netif_rx(skb);
46be265d338833 Stephane Grosjean 2012-03-02 525
46be265d338833 Stephane Grosjean 2012-03-02 526 return 0;
46be265d338833 Stephane Grosjean 2012-03-02 527 }

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]

2021-12-03 14:59:12

by Marc Kleine-Budde

[permalink] [raw]

Subject: Re: drivers/net/can/usb/peak_usb/pcan_usb.c:523 pcan_usb_decode_error() error: we previously assumed 'cf' could be null (see line 503)

On 03.12.2021 17:09:55, Dan Carpenter wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 58e1100fdc5990b0cc0d4beaf2562a92e621ac7d
> commit: c11dcee758302702a83c6e85e4c4c3d9af42d2b3 can: peak_usb: pcan_usb_decode_error(): upgrade handling of bus state changes
> config: x86_64-randconfig-m001-20211202 (https://download.01.org/0day-ci/archive/20211202/[email protected]/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 <[email protected]>
> Reported-by: Dan Carpenter <[email protected]>
>
> smatch warnings:
> drivers/net/can/usb/peak_usb/pcan_usb.c:523 pcan_usb_decode_error() error: we previously assumed 'cf' could be null (see line 503)
>
> vim +/cf +523 drivers/net/can/usb/peak_usb/pcan_usb.c
>
> 46be265d338833 Stephane Grosjean 2012-03-02 450 static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n,
> 46be265d338833 Stephane Grosjean 2012-03-02 451 u8 status_len)
> 46be265d338833 Stephane Grosjean 2012-03-02 452 {
> 46be265d338833 Stephane Grosjean 2012-03-02 453 struct sk_buff *skb;
> 46be265d338833 Stephane Grosjean 2012-03-02 454 struct can_frame *cf;
> c11dcee7583027 Stephane Grosjean 2021-07-15 455 enum can_state new_state = CAN_STATE_ERROR_ACTIVE;
> 46be265d338833 Stephane Grosjean 2012-03-02 456
> 46be265d338833 Stephane Grosjean 2012-03-02 457 /* ignore this error until 1st ts received */
> 46be265d338833 Stephane Grosjean 2012-03-02 458 if (n == PCAN_USB_ERROR_QOVR)
> 46be265d338833 Stephane Grosjean 2012-03-02 459 if (!mc->pdev->time_ref.tick_count)
> 46be265d338833 Stephane Grosjean 2012-03-02 460 return 0;
> 46be265d338833 Stephane Grosjean 2012-03-02 461
> c11dcee7583027 Stephane Grosjean 2021-07-15 462 /* allocate an skb to store the error frame */
> c11dcee7583027 Stephane Grosjean 2021-07-15 463 skb = alloc_can_err_skb(mc->netdev, &cf);

alloc_can_err_skb() ->
alloc_canfd_skb()

https://elixir.bootlin.com/linux/v5.15/source/drivers/net/can/dev/skb.c#L210

If skb is NULL, cf is set to NULL, too.

> 46be265d338833 Stephane Grosjean 2012-03-02 464
> c11dcee7583027 Stephane Grosjean 2021-07-15 465 if (n & PCAN_USB_ERROR_RXQOVR) {
> c11dcee7583027 Stephane Grosjean 2021-07-15 466 /* data overrun interrupt */
> c11dcee7583027 Stephane Grosjean 2021-07-15 467 netdev_dbg(mc->netdev, "data overrun interrupt\n");
> c11dcee7583027 Stephane Grosjean 2021-07-15 468 mc->netdev->stats.rx_over_errors++;
> c11dcee7583027 Stephane Grosjean 2021-07-15 469 mc->netdev->stats.rx_errors++;
> c11dcee7583027 Stephane Grosjean 2021-07-15 470 if (cf) {
>
> Check for NULL
>
> c11dcee7583027 Stephane Grosjean 2021-07-15 471 cf->can_id |= CAN_ERR_CRTL;
> c11dcee7583027 Stephane Grosjean 2021-07-15 472 cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;
> 46be265d338833 Stephane Grosjean 2012-03-02 473 }
> 46be265d338833 Stephane Grosjean 2012-03-02 474 }
> 46be265d338833 Stephane Grosjean 2012-03-02 475
> c11dcee7583027 Stephane Grosjean 2021-07-15 476 if (n & PCAN_USB_ERROR_TXQFULL)
> c11dcee7583027 Stephane Grosjean 2021-07-15 477 netdev_dbg(mc->netdev, "device Tx queue full)\n");
> c11dcee7583027 Stephane Grosjean 2021-07-15 478
> 46be265d338833 Stephane Grosjean 2012-03-02 479 if (n & PCAN_USB_ERROR_BUS_OFF) {
> 46be265d338833 Stephane Grosjean 2012-03-02 480 new_state = CAN_STATE_BUS_OFF;
> c11dcee7583027 Stephane Grosjean 2021-07-15 481 } else if (n & PCAN_USB_ERROR_BUS_HEAVY) {
> c11dcee7583027 Stephane Grosjean 2021-07-15 482 new_state = ((mc->pdev->bec.txerr >= 128) ||
> c11dcee7583027 Stephane Grosjean 2021-07-15 483 (mc->pdev->bec.rxerr >= 128)) ?
> c11dcee7583027 Stephane Grosjean 2021-07-15 484 CAN_STATE_ERROR_PASSIVE :
> c11dcee7583027 Stephane Grosjean 2021-07-15 485 CAN_STATE_ERROR_WARNING;
> c11dcee7583027 Stephane Grosjean 2021-07-15 486 } else {
> c11dcee7583027 Stephane Grosjean 2021-07-15 487 new_state = CAN_STATE_ERROR_ACTIVE;
> 46be265d338833 Stephane Grosjean 2012-03-02 488 }
> 46be265d338833 Stephane Grosjean 2012-03-02 489
> c11dcee7583027 Stephane Grosjean 2021-07-15 490 /* handle change of state */
> c11dcee7583027 Stephane Grosjean 2021-07-15 491 if (new_state != mc->pdev->dev.can.state) {
> c11dcee7583027 Stephane Grosjean 2021-07-15 492 enum can_state tx_state =
> c11dcee7583027 Stephane Grosjean 2021-07-15 493 (mc->pdev->bec.txerr >= mc->pdev->bec.rxerr) ?
> c11dcee7583027 Stephane Grosjean 2021-07-15 494 new_state : 0;
> c11dcee7583027 Stephane Grosjean 2021-07-15 495 enum can_state rx_state =
> c11dcee7583027 Stephane Grosjean 2021-07-15 496 (mc->pdev->bec.txerr <= mc->pdev->bec.rxerr) ?
> c11dcee7583027 Stephane Grosjean 2021-07-15 497 new_state : 0;
> 46be265d338833 Stephane Grosjean 2012-03-02 498
> c11dcee7583027 Stephane Grosjean 2021-07-15 499 can_change_state(mc->netdev, cf, tx_state, rx_state);
> 46be265d338833 Stephane Grosjean 2012-03-02 500
> c11dcee7583027 Stephane Grosjean 2021-07-15 501 if (new_state == CAN_STATE_BUS_OFF) {
> 46be265d338833 Stephane Grosjean 2012-03-02 502 can_bus_off(mc->netdev);
> c11dcee7583027 Stephane Grosjean 2021-07-15 @503 } else if (cf && (cf->can_id & CAN_ERR_CRTL)) {
>
> Check for NULL
>
> c11dcee7583027 Stephane Grosjean 2021-07-15 504 /* Supply TX/RX error counters in case of
> c11dcee7583027 Stephane Grosjean 2021-07-15 505 * controller error.
> c11dcee7583027 Stephane Grosjean 2021-07-15 506 */
> ea8b33bde76c8f Stephane Grosjean 2019-12-06 507 cf->data[6] = mc->pdev->bec.txerr;
> ea8b33bde76c8f Stephane Grosjean 2019-12-06 508 cf->data[7] = mc->pdev->bec.rxerr;
> ea8b33bde76c8f Stephane Grosjean 2019-12-06 509 }
> 46be265d338833 Stephane Grosjean 2012-03-02 510 }
> 46be265d338833 Stephane Grosjean 2012-03-02 511
> c11dcee7583027 Stephane Grosjean 2021-07-15 512 if (!skb)
> c11dcee7583027 Stephane Grosjean 2021-07-15 513 return -ENOMEM;

If cf is NULL, so is skb....

> 46be265d338833 Stephane Grosjean 2012-03-02 514
> 46be265d338833 Stephane Grosjean 2012-03-02 515 if (status_len & PCAN_USB_STATUSLEN_TIMESTAMP) {
> c9faaa09e2a133 Oliver Hartkopp 2012-11-21 516 struct skb_shared_hwtstamps *hwts = skb_hwtstamps(skb);
> c9faaa09e2a133 Oliver Hartkopp 2012-11-21 517
> d5888a1e75c799 Arnd Bergmann 2017-11-03 518 peak_usb_get_ts_time(&mc->pdev->time_ref, mc->ts16,
> d5888a1e75c799 Arnd Bergmann 2017-11-03 519 &hwts->hwtstamp);
> 46be265d338833 Stephane Grosjean 2012-03-02 520 }
> 46be265d338833 Stephane Grosjean 2012-03-02 521
> 46be265d338833 Stephane Grosjean 2012-03-02 522 mc->netdev->stats.rx_packets++;
> c7b74967799b1a Oliver Hartkopp 2020-11-20 @523 mc->netdev->stats.rx_bytes += cf->len;
> ^^^^^^^^
> No check for NULL.

...then this code is not reached.

Marc

--
Pengutronix e.K. | Marc Kleine-Budde |
Embedded Linux | https://www.pengutronix.de |
Vertretung West/Dortmund | Phone: +49-231-2826-924 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |

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2021-12-03 15:01:54

by Marc Kleine-Budde

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Subject: Re: drivers/net/can/usb/peak_usb/pcan_usb.c:523 pcan_usb_decode_error() error: we previously assumed 'cf' could be null (see line 503)

On 03.12.2021 15:58:52, Marc Kleine-Budde wrote:
> On 03.12.2021 17:09:55, Dan Carpenter wrote:
> > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> > head: 58e1100fdc5990b0cc0d4beaf2562a92e621ac7d
> > commit: c11dcee758302702a83c6e85e4c4c3d9af42d2b3 can: peak_usb: pcan_usb_decode_error(): upgrade handling of bus state changes
> > config: x86_64-randconfig-m001-20211202 (https://download.01.org/0day-ci/archive/20211202/[email protected]/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 <[email protected]>
> > Reported-by: Dan Carpenter <[email protected]>
> >
> > smatch warnings:
> > drivers/net/can/usb/peak_usb/pcan_usb.c:523 pcan_usb_decode_error() error: we previously assumed 'cf' could be null (see line 503)
> >
> > vim +/cf +523 drivers/net/can/usb/peak_usb/pcan_usb.c
> >
> > 46be265d338833 Stephane Grosjean 2012-03-02 450 static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n,
> > 46be265d338833 Stephane Grosjean 2012-03-02 451 u8 status_len)
> > 46be265d338833 Stephane Grosjean 2012-03-02 452 {
> > 46be265d338833 Stephane Grosjean 2012-03-02 453 struct sk_buff *skb;
> > 46be265d338833 Stephane Grosjean 2012-03-02 454 struct can_frame *cf;
> > c11dcee7583027 Stephane Grosjean 2021-07-15 455 enum can_state new_state = CAN_STATE_ERROR_ACTIVE;
> > 46be265d338833 Stephane Grosjean 2012-03-02 456
> > 46be265d338833 Stephane Grosjean 2012-03-02 457 /* ignore this error until 1st ts received */
> > 46be265d338833 Stephane Grosjean 2012-03-02 458 if (n == PCAN_USB_ERROR_QOVR)
> > 46be265d338833 Stephane Grosjean 2012-03-02 459 if (!mc->pdev->time_ref.tick_count)
> > 46be265d338833 Stephane Grosjean 2012-03-02 460 return 0;
> > 46be265d338833 Stephane Grosjean 2012-03-02 461
> > c11dcee7583027 Stephane Grosjean 2021-07-15 462 /* allocate an skb to store the error frame */
> > c11dcee7583027 Stephane Grosjean 2021-07-15 463 skb = alloc_can_err_skb(mc->netdev, &cf);
>
> alloc_can_err_skb() ->
> alloc_canfd_skb()

Doh! It calls alloc_can_skb()

https://elixir.bootlin.com/linux/v5.15/source/drivers/net/can/dev/skb.c#L180

Marc

--
Pengutronix e.K. | Marc Kleine-Budde |
Embedded Linux | https://www.pengutronix.de |
Vertretung West/Dortmund | Phone: +49-231-2826-924 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |

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2021-12-03 15:15:24

by Dan Carpenter

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Subject: Re: drivers/net/can/usb/peak_usb/pcan_usb.c:523 pcan_usb_decode_error() error: we previously assumed 'cf' could be null (see line 503)

On Fri, Dec 03, 2021 at 03:58:51PM +0100, Marc Kleine-Budde wrote:
> >
> > 46be265d338833 Stephane Grosjean 2012-03-02 450 static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n,
> > 46be265d338833 Stephane Grosjean 2012-03-02 451 u8 status_len)
> > 46be265d338833 Stephane Grosjean 2012-03-02 452 {
> > 46be265d338833 Stephane Grosjean 2012-03-02 453 struct sk_buff *skb;
> > 46be265d338833 Stephane Grosjean 2012-03-02 454 struct can_frame *cf;
> > c11dcee7583027 Stephane Grosjean 2021-07-15 455 enum can_state new_state = CAN_STATE_ERROR_ACTIVE;
> > 46be265d338833 Stephane Grosjean 2012-03-02 456
> > 46be265d338833 Stephane Grosjean 2012-03-02 457 /* ignore this error until 1st ts received */
> > 46be265d338833 Stephane Grosjean 2012-03-02 458 if (n == PCAN_USB_ERROR_QOVR)
> > 46be265d338833 Stephane Grosjean 2012-03-02 459 if (!mc->pdev->time_ref.tick_count)
> > 46be265d338833 Stephane Grosjean 2012-03-02 460 return 0;
> > 46be265d338833 Stephane Grosjean 2012-03-02 461
> > c11dcee7583027 Stephane Grosjean 2021-07-15 462 /* allocate an skb to store the error frame */
> > c11dcee7583027 Stephane Grosjean 2021-07-15 463 skb = alloc_can_err_skb(mc->netdev, &cf);
>
> alloc_can_err_skb() ->
> alloc_canfd_skb()
>
> https://elixir.bootlin.com/linux/v5.15/source/drivers/net/can/dev/skb.c#L210
>
> If skb is NULL, cf is set to NULL, too.

Yeah. Sorry about that. The kbuild-bot doesn't do much cross function
analysis (none for functions that are not inline). I saw that this
patch was old and could easily have checked it on my system which has
the cross function DB but I was in a rush. :/ My bad. Will try be a
more diligent person next time.

regards,
dan carpenter