* [PATCH] staging: rtl8712: Fix pointer dereferenced before checking
@ 2022-05-30 8:05 Haowen Bai
2022-05-30 8:14 ` Greg Kroah-Hartman
2022-05-30 9:29 ` Dan Carpenter
0 siblings, 2 replies; 6+ messages in thread
From: Haowen Bai @ 2022-05-30 8:05 UTC (permalink / raw)
To: Larry Finger, Florian Schilhabel, Greg Kroah-Hartman
Cc: Haowen Bai, linux-staging, linux-kernel
The padapter->recvpriv.signal_qual_data is dereferencing before null
checking, so move it after checking.
Signed-off-by: Haowen Bai <baihaowen@meizu.com>
---
drivers/staging/rtl8712/rtl8712_recv.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/staging/rtl8712/rtl8712_recv.c b/drivers/staging/rtl8712/rtl8712_recv.c
index 7f1fdd058551..8ed94b259dbe 100644
--- a/drivers/staging/rtl8712/rtl8712_recv.c
+++ b/drivers/staging/rtl8712/rtl8712_recv.c
@@ -863,10 +863,12 @@ static void process_link_qual(struct _adapter *padapter,
{
u32 last_evm = 0, tmpVal;
struct rx_pkt_attrib *pattrib;
- struct smooth_rssi_data *sqd = &padapter->recvpriv.signal_qual_data;
+ struct smooth_rssi_data *sqd;
if (!prframe || !padapter)
return;
+
+ sqd = &padapter->recvpriv.signal_qual_data;
pattrib = &prframe->u.hdr.attrib;
if (pattrib->signal_qual != 0) {
/*
--
2.7.4
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH] staging: rtl8712: Fix pointer dereferenced before checking
2022-05-30 8:05 [PATCH] staging: rtl8712: Fix pointer dereferenced before checking Haowen Bai
@ 2022-05-30 8:14 ` Greg Kroah-Hartman
2022-05-30 8:22 ` baihaowen
2022-05-30 9:29 ` Dan Carpenter
1 sibling, 1 reply; 6+ messages in thread
From: Greg Kroah-Hartman @ 2022-05-30 8:14 UTC (permalink / raw)
To: Haowen Bai; +Cc: Larry Finger, Florian Schilhabel, linux-staging, linux-kernel
On Mon, May 30, 2022 at 04:05:32PM +0800, Haowen Bai wrote:
> The padapter->recvpriv.signal_qual_data is dereferencing before null
> checking, so move it after checking.
>
> Signed-off-by: Haowen Bai <baihaowen@meizu.com>
> ---
> drivers/staging/rtl8712/rtl8712_recv.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/staging/rtl8712/rtl8712_recv.c b/drivers/staging/rtl8712/rtl8712_recv.c
> index 7f1fdd058551..8ed94b259dbe 100644
> --- a/drivers/staging/rtl8712/rtl8712_recv.c
> +++ b/drivers/staging/rtl8712/rtl8712_recv.c
> @@ -863,10 +863,12 @@ static void process_link_qual(struct _adapter *padapter,
> {
> u32 last_evm = 0, tmpVal;
> struct rx_pkt_attrib *pattrib;
> - struct smooth_rssi_data *sqd = &padapter->recvpriv.signal_qual_data;
> + struct smooth_rssi_data *sqd;
>
> if (!prframe || !padapter)
> return;
> +
> + sqd = &padapter->recvpriv.signal_qual_data;
How can padapter ever be NULL in this codepath?
thanks,
greg k-h
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] staging: rtl8712: Fix pointer dereferenced before checking
2022-05-30 8:14 ` Greg Kroah-Hartman
@ 2022-05-30 8:22 ` baihaowen
2022-05-30 8:26 ` Greg Kroah-Hartman
0 siblings, 1 reply; 6+ messages in thread
From: baihaowen @ 2022-05-30 8:22 UTC (permalink / raw)
To: Greg Kroah-Hartman
Cc: Larry Finger, Florian Schilhabel, linux-staging, linux-kernel
在 2022/5/30 下午4:14, Greg Kroah-Hartman 写道:
> On Mon, May 30, 2022 at 04:05:32PM +0800, Haowen Bai wrote:
>> The padapter->recvpriv.signal_qual_data is dereferencing before null
>> checking, so move it after checking.
>>
>> Signed-off-by: Haowen Bai <baihaowen@meizu.com>
>> ---
>> drivers/staging/rtl8712/rtl8712_recv.c | 4 +++-
>> 1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/staging/rtl8712/rtl8712_recv.c b/drivers/staging/rtl8712/rtl8712_recv.c
>> index 7f1fdd058551..8ed94b259dbe 100644
>> --- a/drivers/staging/rtl8712/rtl8712_recv.c
>> +++ b/drivers/staging/rtl8712/rtl8712_recv.c
>> @@ -863,10 +863,12 @@ static void process_link_qual(struct _adapter *padapter,
>> {
>> u32 last_evm = 0, tmpVal;
>> struct rx_pkt_attrib *pattrib;
>> - struct smooth_rssi_data *sqd = &padapter->recvpriv.signal_qual_data;
>> + struct smooth_rssi_data *sqd;
>>
>> if (!prframe || !padapter)
>> return;
>> +
>> + sqd = &padapter->recvpriv.signal_qual_data;
> How can padapter ever be NULL in this codepath?
>
> thanks,
>
> greg k-h
Just the original code, show me
if (!prframe || !padapter)
It would be null, and then return.
--
Haowen Bai
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] staging: rtl8712: Fix pointer dereferenced before checking
2022-05-30 8:22 ` baihaowen
@ 2022-05-30 8:26 ` Greg Kroah-Hartman
2022-05-30 8:44 ` baihaowen
0 siblings, 1 reply; 6+ messages in thread
From: Greg Kroah-Hartman @ 2022-05-30 8:26 UTC (permalink / raw)
To: baihaowen; +Cc: Larry Finger, Florian Schilhabel, linux-staging, linux-kernel
On Mon, May 30, 2022 at 04:22:11PM +0800, baihaowen wrote:
> 在 2022/5/30 下午4:14, Greg Kroah-Hartman 写道:
> > On Mon, May 30, 2022 at 04:05:32PM +0800, Haowen Bai wrote:
> >> The padapter->recvpriv.signal_qual_data is dereferencing before null
> >> checking, so move it after checking.
> >>
> >> Signed-off-by: Haowen Bai <baihaowen@meizu.com>
> >> ---
> >> drivers/staging/rtl8712/rtl8712_recv.c | 4 +++-
> >> 1 file changed, 3 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/staging/rtl8712/rtl8712_recv.c b/drivers/staging/rtl8712/rtl8712_recv.c
> >> index 7f1fdd058551..8ed94b259dbe 100644
> >> --- a/drivers/staging/rtl8712/rtl8712_recv.c
> >> +++ b/drivers/staging/rtl8712/rtl8712_recv.c
> >> @@ -863,10 +863,12 @@ static void process_link_qual(struct _adapter *padapter,
> >> {
> >> u32 last_evm = 0, tmpVal;
> >> struct rx_pkt_attrib *pattrib;
> >> - struct smooth_rssi_data *sqd = &padapter->recvpriv.signal_qual_data;
> >> + struct smooth_rssi_data *sqd;
> >>
> >> if (!prframe || !padapter)
> >> return;
> >> +
> >> + sqd = &padapter->recvpriv.signal_qual_data;
> > How can padapter ever be NULL in this codepath?
> >
> > thanks,
> >
> > greg k-h
> Just the original code, show me
>
> if (!prframe || !padapter)
>
> It would be null, and then return.
Again, trace things backwards, how can padapter ever be NULL?
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] staging: rtl8712: Fix pointer dereferenced before checking
2022-05-30 8:26 ` Greg Kroah-Hartman
@ 2022-05-30 8:44 ` baihaowen
0 siblings, 0 replies; 6+ messages in thread
From: baihaowen @ 2022-05-30 8:44 UTC (permalink / raw)
To: Greg Kroah-Hartman
Cc: Larry Finger, Florian Schilhabel, linux-staging, linux-kernel
在 2022/5/30 下午4:26, Greg Kroah-Hartman 写道:
> On Mon, May 30, 2022 at 04:22:11PM +0800, baihaowen wrote:
>> 在 2022/5/30 下午4:14, Greg Kroah-Hartman 写道:
>>> On Mon, May 30, 2022 at 04:05:32PM +0800, Haowen Bai wrote:
>>>> The padapter->recvpriv.signal_qual_data is dereferencing before null
>>>> checking, so move it after checking.
>>>>
>>>> Signed-off-by: Haowen Bai <baihaowen@meizu.com>
>>>> ---
>>>> drivers/staging/rtl8712/rtl8712_recv.c | 4 +++-
>>>> 1 file changed, 3 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/staging/rtl8712/rtl8712_recv.c b/drivers/staging/rtl8712/rtl8712_recv.c
>>>> index 7f1fdd058551..8ed94b259dbe 100644
>>>> --- a/drivers/staging/rtl8712/rtl8712_recv.c
>>>> +++ b/drivers/staging/rtl8712/rtl8712_recv.c
>>>> @@ -863,10 +863,12 @@ static void process_link_qual(struct _adapter *padapter,
>>>> {
>>>> u32 last_evm = 0, tmpVal;
>>>> struct rx_pkt_attrib *pattrib;
>>>> - struct smooth_rssi_data *sqd = &padapter->recvpriv.signal_qual_data;
>>>> + struct smooth_rssi_data *sqd;
>>>>
>>>> if (!prframe || !padapter)
>>>> return;
>>>> +
>>>> + sqd = &padapter->recvpriv.signal_qual_data;
>>> How can padapter ever be NULL in this codepath?
>>>
>>> thanks,
>>>
>>> greg k-h
>> Just the original code, show me
>>
>> if (!prframe || !padapter)
>>
>> It would be null, and then return.
> Again, trace things backwards, how can padapter ever be NULL?
padapter will not be null, since it's initialized by netdev_priv(pnetdev) and return if pnetdev is null. r871xu_drv_init() ...... pnetdev = r8712_init_netdev(); if (!pnetdev) goto error; padapter = netdev_priv(pnetdev); status = r8712_init_drv_sw(padapter); ......
--
Haowen Bai
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] staging: rtl8712: Fix pointer dereferenced before checking
2022-05-30 8:05 [PATCH] staging: rtl8712: Fix pointer dereferenced before checking Haowen Bai
2022-05-30 8:14 ` Greg Kroah-Hartman
@ 2022-05-30 9:29 ` Dan Carpenter
1 sibling, 0 replies; 6+ messages in thread
From: Dan Carpenter @ 2022-05-30 9:29 UTC (permalink / raw)
To: Haowen Bai
Cc: Larry Finger, Florian Schilhabel, Greg Kroah-Hartman,
linux-staging, linux-kernel
On Mon, May 30, 2022 at 04:05:32PM +0800, Haowen Bai wrote:
> The padapter->recvpriv.signal_qual_data is dereferencing before null
> checking, so move it after checking.
>
> Signed-off-by: Haowen Bai <baihaowen@meizu.com>
> ---
> drivers/staging/rtl8712/rtl8712_recv.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/staging/rtl8712/rtl8712_recv.c b/drivers/staging/rtl8712/rtl8712_recv.c
> index 7f1fdd058551..8ed94b259dbe 100644
> --- a/drivers/staging/rtl8712/rtl8712_recv.c
> +++ b/drivers/staging/rtl8712/rtl8712_recv.c
> @@ -863,10 +863,12 @@ static void process_link_qual(struct _adapter *padapter,
> {
> u32 last_evm = 0, tmpVal;
> struct rx_pkt_attrib *pattrib;
> - struct smooth_rssi_data *sqd = &padapter->recvpriv.signal_qual_data;
> + struct smooth_rssi_data *sqd;
This is not a dereference.
>
> if (!prframe || !padapter)
> return;
Not a bug.
Also I agree with your other email that "padapter" cannot be NULL so
the NULL check can be safely deleted.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-05-30 9:30 UTC | newest]
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2022-05-30 8:05 [PATCH] staging: rtl8712: Fix pointer dereferenced before checking Haowen Bai
2022-05-30 8:14 ` Greg Kroah-Hartman
2022-05-30 8:22 ` baihaowen
2022-05-30 8:26 ` Greg Kroah-Hartman
2022-05-30 8:44 ` baihaowen
2022-05-30 9:29 ` Dan Carpenter
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