[PATCH] can: sja1000: fix netdev leak for non-contiguous channels

[PATCH] can: sja1000: fix netdev leak for non-contiguous channels

[Wentao Liang]

pcan_add_channels() stores a registered net_device at card->channel[i],
where i is the hardware channel index, but only increments
card->chan_count by one. When a lower channel is absent or fails to
register and a higher one succeeds, chan_count no longer covers the
used slot. pcan_free_channels() then iterates only up to chan_count and
leaks the net_device of the higher channel; the LED timer and the
interrupt handler also skip it.

Record the highest used channel index plus one in chan_count so that
every iterator covers all channel slots.

Fixes: 2b61972b7421 ("can: sja1000: add support for PEAK-System PCMCIA card")
Cc: stable@vger.kernel.org
Assisted-by: DeepSeek-V4.1-Flash and OpenAI Codex
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
---
 drivers/net/can/sja1000/peak_pcmcia.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/can/sja1000/peak_pcmcia.c b/drivers/net/can/sja1000/peak_pcmcia.c
index c3c2aa21da47..bba51dd808f8 100644
--- a/drivers/net/can/sja1000/peak_pcmcia.c
+++ b/drivers/net/can/sja1000/peak_pcmcia.c
@@ -574,7 +574,7 @@ static int pcan_add_channels(struct pcan_pccard *card)
 		}
 
 		card->channel[i].netdev = netdev;
-		card->chan_count++;
+		card->chan_count = i + 1;
 
 		/* set corresponding led on in the new ccr */
 		ccr &= ~PCC_CCR_LED_OFF_CHAN(i);
-- 
2.34.1

Re: [PATCH] can: sja1000: fix netdev leak for non-contiguous channels

[Krzysztof Kozlowski]

On Tue, 03 Nov 2026 10:05:28 +0000, Wentao Liang wrote:
> pcan_add_channels() stores a registered net_device at card->channel[i],
> where i is the hardware channel index, but only increments
> card->chan_count by one. When a lower channel is absent or fails to
> register and a higher one succeeds, chan_count no longer covers the
> used slot. pcan_free_channels() then iterates only up to chan_count and
> leaks the net_device of the higher channel; the LED timer and the
> interrupt handler also skip it.
> 
> Record the highest used channel index plus one in chan_count so that
> every iterator covers all channel slots.
> 
> Fixes: 2b61972b7421 ("can: sja1000: add support for PEAK-System PCMCIA card")
> Cc: stable@vger.kernel.org
> Assisted-by: DeepSeek-V4.1-Flash and OpenAI Codex
> Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
> ---
>  drivers/net/can/sja1000/peak_pcmcia.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 



Multiple things here:
1. Your team ignored completely previous feedback. Multiple times.

2. You use multiple identities with this email address, thus I doubt that we
   speak with an actual person.

3. Your bot does not even bother running checkpatch, right?

4. Nothing of this was reproduced nor tested.

5. Finally, the same feedback:
You sent multiple independent patches, to multiple independent
subsystems. The amount of these patches clearly suggest this was
AI generated and most likely not tested.

More importantly, you sent all this work without properly organizing
relevant patches into patchsets. This makes reviewing difficult
and might cause multiple reviewers to address the same issue.
Replying to the entire set is impossible and requires handling each
patch independently, instead of applying or discarding the set.
Maintainers also won't see the bigger picture of your work. Quite
worrying.

This is on the verge of hostile patch: bomb us with so many
contributions, we won't be able to handle them in efficient manner,
like responding ONCE to ask you to slow down.  Considering all this
is untested and LLM generated, I have even more doubts whether this
should be considered for review.

Please read kernel documentation BEFORE posting more work. It will
explain you how to identify subsystems, how to organize your work per
subsystem (so a patchset grouping multiple patches with a short cover
letter), how to document the issue discovery method and what was
or was not tested.

Best regards,
Krzysztof