Subject: Re: [PATCH v2] wifi: mt76: mt7921: fix resource leak in probe error path

From: Hongling Zeng <[email-masked]>
Date: Wed, 27 May 2026 13:35:12 +0800

Hi Sean,

   Thanks for the review! You're absolutely right about the incorrect 
Fixes: tag.

   Here's v3 with the correct Fixes tags pointing to the actual commits that
   introduced the resource leaks:

   - ee5bb35d2b83 introduced the pcim_iomap_region() direct return
   - 222606f43b58 introduced the devm_kmemdup() direct return

   Thanks again for catching that.

   Regards,
   Hongling

在 2026年05月27日 12:48, Sean Wang 写道:
> Hi,
>
> On Tue, May 26, 2026 at 10:44 PM Hongling Zeng <[email-masked]> wrote:
>> When pcim_iomap_region() or devm_kmemdup() fail, the code returns
>> directly without cleaning up previously allocated resources:
>>    - mt76_device allocated by mt76_alloc_device()
>>    - pci irq vectors allocated by pci_alloc_irq_vectors()
>> Fix this by jumping to the existing error cleanup path instead of
>> returning directly.
>>
>> To avoid using an uninitialized variable in the error path, move the
>> dev initialization before the error checks.
>>
>> Fixes: 234738ea3390 ("phy: ti-pipe3: move clk initialization to a separate function")
>> Signed-off-by: Hongling Zeng <[email-masked]>
>>
> The code change itself looks correct, but commit message Fixes: tag is wrong.
>
> It points to 234738ea3390 ("phy: ti-pipe3: move clk initialization to
> a separate function"), which is unrelated to mt76/mt7921.
>
> The two direct-return leaks appear to come from:
>        - ee5bb35d2b83 ("wifi: mt76: mt7921: Replace deprecated PCI
> function") for the pcim_iomap_region() path.
>        - 222606f43b58 ("wifi: mt76: mt7921: handle MT7902 irq_map quirk
> with mutable copy") for the MT7902 devm_kmemdup() path.
>
>> ---
>>   Change in v1
>>     --fix uninitialized variable warning
>> ---
>>   drivers/net/wireless/mediatek/mt76/mt7921/pci.c | 15 ++++++++++-----
>>   1 file changed, 10 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
>> index 7a790ddf43bb..49a37185f056 100644
>> --- a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
>> +++ b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
>> @@ -343,11 +343,14 @@ static int mt7921_pci_probe(struct pci_dev *pdev,
>>
>>          pci_set_drvdata(pdev, mdev);
>>
>> +       dev = container_of(mdev, struct mt792x_dev, mt76);
>> +
>>          regs =  pcim_iomap_region(pdev, 0, pci_name(pdev));
>> -       if (IS_ERR(regs))
>> -               return PTR_ERR(regs);
>> +       if (IS_ERR(regs)) {
>> +               ret = PTR_ERR(regs);
>> +               goto err_free_dev;
>> +       }
>>
>> -       dev = container_of(mdev, struct mt792x_dev, mt76);
>>          dev->fw_features = features;
>>          dev->hif_ops = &mt7921_pcie_ops;
>>          dev->irq_map = &irq_map;
>> @@ -359,8 +362,10 @@ static int mt7921_pci_probe(struct pci_dev *pdev,
>>                  /* MT7902 needs a mutable copy because wm2_complete_mask differs */
>>                  map = devm_kmemdup(&pdev->dev, &irq_map,
>>                                     sizeof(irq_map), GFP_KERNEL);
>> -               if (!map)
>> -                       return -ENOMEM;
>> +               if (!map) {
>> +                       ret = -ENOMEM;
>> +                       goto err_free_dev;
>> +               }
>>
>>                  map->rx.wm2_complete_mask = 0;
>>                  dev->irq_map = map;
>> --
>> 2.25.1
>>
>>