On 2025/1/11 17:01, Krzysztof Kozlowski wrote:
> On Sat, Jan 11, 2025 at 06:34:21AM +0800, Zijun Hu wrote:
>> On 2025/1/11 04:26, Rob Herring wrote:
>>> On Thu, Jan 09, 2025 at 09:26:57PM +0800, Zijun Hu wrote:
>>>> From: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
>>>>
>>>> parse_interrupt_map() will use uninitialized variable @imaplen if fails
>>>> to get property 'interrupt-map'.
>>>>
>>>> Fix by using the variable after successfully getting the property.
>>>>
>>>> Fixes: e7985f43609c ("of: property: Fix fw_devlink handling of interrupt-map")
>>>> Signed-off-by: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
>>>> ---
>>>> drivers/of/property.c | 2 +-
>>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/of/property.c b/drivers/of/property.c
>>>> index dca1a3ebccae1093b2b11f51e8e692bca854d0e3..6245cbff3527d762c16e7f4b7b7b3d4f2e9ddbe6 100644
>>>> --- a/drivers/of/property.c
>>>> +++ b/drivers/of/property.c
>>>> @@ -1391,9 +1391,9 @@ static struct device_node *parse_interrupt_map(struct device_node *np,
>>>> addrcells = of_bus_n_addr_cells(np);
>>>>
>>>> imap = of_get_property(np, "interrupt-map", &imaplen);
>>>> - imaplen /= sizeof(*imap);
>>>> if (!imap)
>>>> return NULL;
>>>> + imaplen /= sizeof(*imap);
>>>
>>> sizeof() is a compile time constant, there's not an actual dereference
>>> here.
>>>
>>
>> the uninitialized variable is @imaplen, and not sizeof(*imap).
>
> Correct. I think error is harmless, because whatever stack/random value
> of imaplen we use in 'imaplen / =sizeof', we immediately return.
>
> Anyway, for code correctness and silencing whatever warnings there are
> (if there are you should actually paste them in commit msg):
>
thank you Krzysztof Kozlowski for code review.
no warning messages since this issue is found by reading code.
> Reviewed-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
>
> Best regards,
> Krzysztof
>
