2021-03-04 12:08:23

by Ray Chi

Subject: Re: [PATCH] usb: dwc3: Fix dereferencing of null dwc->usb_psy

On Wed, Mar 3, 2021 at 6:00 PM Colin King <[email protected]> wrote:
>
> From: Colin Ian King <[email protected]>
>
> Currently the null check logic on dwc->usb_psy is inverted as it allows
> calls to power_supply_put with a null dwc->usb_psy causing a null
> pointer dereference. Fix this by removing the ! operator.
>
> Addresses-Coverity: ("Dereference after null check")
> Fixes: 59fa3def35de ("usb: dwc3: add a power supply for current control")

Acked-by: Ray Chi <[email protected]>

> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/usb/dwc3/core.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index d15f065849cd..94fdbe502ce9 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -1628,7 +1628,7 @@ static int dwc3_probe(struct platform_device *pdev)
> assert_reset:
> reset_control_assert(dwc->reset);
>
> - if (!dwc->usb_psy)
> + if (dwc->usb_psy)
> power_supply_put(dwc->usb_psy);
>
> return ret;
> @@ -1653,7 +1653,7 @@ static int dwc3_remove(struct platform_device *pdev)
> dwc3_free_event_buffers(dwc);
> dwc3_free_scratch_buffers(dwc);
>
> - if (!dwc->usb_psy)
> + if (dwc->usb_psy)
> power_supply_put(dwc->usb_psy);
>
> return 0;
> --
> 2.30.0
>

Thanks for fixing this bug!

Regards,
Ray

2021-03-04 13:07:04

by Heiko Thiery

Subject: Re: [PATCH] usb: dwc3: Fix dereferencing of null dwc->usb_psy

Hi all,

> On Wed, Mar 3, 2021 at 6:00 PM Colin King <[email protected]> wrote:
>>
>> From: Colin Ian King <[email protected]>
>>
>> Currently the null check logic on dwc->usb_psy is inverted as it allows
>> calls to power_supply_put with a null dwc->usb_psy causing a null
>> pointer dereference. Fix this by removing the ! operator.
>>
>> Addresses-Coverity: ("Dereference after null check")
>> Fixes: 59fa3def35de ("usb: dwc3: add a power supply for current control")
>
> Acked-by: Ray Chi <[email protected]>
>
>> Signed-off-by: Colin Ian King <[email protected]>

Tested-by: Heiko Thiery <[email protected]>

>> ---
>> drivers/usb/dwc3/core.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>> index d15f065849cd..94fdbe502ce9 100644
>> --- a/drivers/usb/dwc3/core.c
>> +++ b/drivers/usb/dwc3/core.c
>> @@ -1628,7 +1628,7 @@ static int dwc3_probe(struct platform_device *pdev)
>> assert_reset:
>> reset_control_assert(dwc->reset);
>>
>> - if (!dwc->usb_psy)
>> + if (dwc->usb_psy)
>> power_supply_put(dwc->usb_psy);
>>
>> return ret;
>> @@ -1653,7 +1653,7 @@ static int dwc3_remove(struct platform_device *pdev)
>> dwc3_free_event_buffers(dwc);
>> dwc3_free_scratch_buffers(dwc);
>>
>> - if (!dwc->usb_psy)
>> + if (dwc->usb_psy)
>> power_supply_put(dwc->usb_psy);
>>
>> return 0;
>> --
>> 2.30.0
>>

Thank you.

--
Heiko

2021-03-04 13:28:57

by Colin King

Subject: Re: [PATCH] usb: dwc3: Fix dereferencing of null dwc->usb_psy

On 03/03/2021 21:29, Heiko Thiery wrote:
> Hi all,
>
>> On Wed, Mar 3, 2021 at 6:00 PM Colin King <[email protected]> wrote:
>>>
>>> From: Colin Ian King <[email protected]>
>>>
>>> Currently the null check logic on dwc->usb_psy is inverted as it allows
>>> calls to power_supply_put with a null dwc->usb_psy causing a null
>>> pointer dereference. Fix this by removing the ! operator.
>>>
>>> Addresses-Coverity: ("Dereference after null check")
>>> Fixes: 59fa3def35de ("usb: dwc3: add a power supply for current control")
>>
>> Acked-by: Ray Chi <[email protected]>
>>
>>> Signed-off-by: Colin Ian King <[email protected]>
>
> Tested-by: Heiko Thiery <[email protected]>

Thanks for testing. Much appreciated.

Colin
>
>>> ---
>>> drivers/usb/dwc3/core.c | 4 ++--
>>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>>> index d15f065849cd..94fdbe502ce9 100644
>>> --- a/drivers/usb/dwc3/core.c
>>> +++ b/drivers/usb/dwc3/core.c
>>> @@ -1628,7 +1628,7 @@ static int dwc3_probe(struct platform_device *pdev)
>>> assert_reset:
>>> reset_control_assert(dwc->reset);
>>>
>>> - if (!dwc->usb_psy)
>>> + if (dwc->usb_psy)
>>> power_supply_put(dwc->usb_psy);
>>>
>>> return ret;
>>> @@ -1653,7 +1653,7 @@ static int dwc3_remove(struct platform_device *pdev)
>>> dwc3_free_event_buffers(dwc);
>>> dwc3_free_scratch_buffers(dwc);
>>>
>>> - if (!dwc->usb_psy)
>>> + if (dwc->usb_psy)
>>> power_supply_put(dwc->usb_psy);
>>>
>>> return 0;
>>> --
>>> 2.30.0
>>>
>
> Thank you.
>