[Intel-wired-lan] [PATCH] i40e: fix MMIO write access to an invalid page in i40e_clear_hw

[Intel-wired-lan] [PATCH] i40e: fix MMIO write access to an invalid page in i40e_clear_hw

[Kyungwook Boo]

In i40e_clear_hw(), when the device sends a specific input(e.g., 0),
an integer underflow in the num_{pf,vf}_int variables can occur,
leading to MMIO write access to an invalid page.

To fix this, we change the type of the unsigned integer variables
num_{pf,vf}_int to signed integers. Additionally, in the for-loop where the
integer underflow occurs, we also change the type of the loop variable i to
a signed integer.

Signed-off-by: Kyungwook Boo <bookyungwook@gmail.com>
Signed-off-by: Loktionov, Aleksandr <aleksandr.loktionov@intel.com>
Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://lore.kernel.org/lkml/ffc91764-1142-4ba2-91b6-8c773f6f7095@gmail.com/T/
---
 drivers/net/ethernet/intel/i40e/i40e_common.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_common.c b/drivers/net/ethernet/intel/i40e/i40e_common.c
index 370b4bddee44..9a73cb94dc5e 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_common.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_common.c
@@ -817,8 +817,8 @@ int i40e_pf_reset(struct i40e_hw *hw)
 void i40e_clear_hw(struct i40e_hw *hw)
 {
 	u32 num_queues, base_queue;
-	u32 num_pf_int;
-	u32 num_vf_int;
+	s32 num_pf_int;
+	s32 num_vf_int;
 	u32 num_vfs;
 	u32 i, j;
 	u32 val;
@@ -848,18 +848,18 @@ void i40e_clear_hw(struct i40e_hw *hw)
 	/* stop all the interrupts */
 	wr32(hw, I40E_PFINT_ICR0_ENA, 0);
 	val = 0x3 << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT;
-	for (i = 0; i < num_pf_int - 2; i++)
+	for (s32 i = 0; i < num_pf_int - 2; i++)
 		wr32(hw, I40E_PFINT_DYN_CTLN(i), val);
 
 	/* Set the FIRSTQ_INDX field to 0x7FF in PFINT_LNKLSTx */
 	val = eol << I40E_PFINT_LNKLST0_FIRSTQ_INDX_SHIFT;
 	wr32(hw, I40E_PFINT_LNKLST0, val);
-	for (i = 0; i < num_pf_int - 2; i++)
+	for (s32 i = 0; i < num_pf_int - 2; i++)
 		wr32(hw, I40E_PFINT_LNKLSTN(i), val);
 	val = eol << I40E_VPINT_LNKLST0_FIRSTQ_INDX_SHIFT;
 	for (i = 0; i < num_vfs; i++)
 		wr32(hw, I40E_VPINT_LNKLST0(i), val);
-	for (i = 0; i < num_vf_int - 2; i++)
+	for (s32 i = 0; i < num_vf_int - 2; i++)
 		wr32(hw, I40E_VPINT_LNKLSTN(i), val);
 
 	/* warn the HW of the coming Tx disables */
-- 
2.25.1

Re: [Intel-wired-lan] [PATCH] i40e: fix MMIO write access to an invalid page in i40e_clear_hw

[Przemek Kitszel]

On 3/6/25 06:25, Kyungwook Boo wrote:
> In i40e_clear_hw(), when the device sends a specific input(e.g., 0),
> an integer underflow in the num_{pf,vf}_int variables can occur,
> leading to MMIO write access to an invalid page.
> 
> To fix this, we change the type of the unsigned integer variables
> num_{pf,vf}_int to signed integers. Additionally, in the for-loop where the
> integer underflow occurs, we also change the type of the loop variable i to
> a signed integer.
> 
> Signed-off-by: Kyungwook Boo <bookyungwook@gmail.com>
> Signed-off-by: Loktionov, Aleksandr <aleksandr.loktionov@intel.com>

when Alex said "make sure I signed too" he meant:
"make sure the variable @i is signed too", not the Sign-off ;)

(please wait 24h for the next submission, and also put "iwl-next" after
the "PATCH" word)

> Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>

I didn't signed that either

> Link: https://lore.kernel.org/lkml/ffc91764-1142-4ba2-91b6-8c773f6f7095@gmail.com/T/
> ---
>   drivers/net/ethernet/intel/i40e/i40e_common.c | 10 +++++-----
>   1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/i40e/i40e_common.c b/drivers/net/ethernet/intel/i40e/i40e_common.c
> index 370b4bddee44..9a73cb94dc5e 100644
> --- a/drivers/net/ethernet/intel/i40e/i40e_common.c
> +++ b/drivers/net/ethernet/intel/i40e/i40e_common.c
> @@ -817,8 +817,8 @@ int i40e_pf_reset(struct i40e_hw *hw)
>   void i40e_clear_hw(struct i40e_hw *hw)
>   {
>   	u32 num_queues, base_queue;
> -	u32 num_pf_int;
> -	u32 num_vf_int;
> +	s32 num_pf_int;
> +	s32 num_vf_int;
>   	u32 num_vfs;
>   	u32 i, j;

It's fine to move the declaration of @i into the for loop, but
you have to remove it here, otherwise it's shadowing, which we
avoid.

>   	u32 val;
> @@ -848,18 +848,18 @@ void i40e_clear_hw(struct i40e_hw *hw)
>   	/* stop all the interrupts */
>   	wr32(hw, I40E_PFINT_ICR0_ENA, 0);
>   	val = 0x3 << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT;
> -	for (i = 0; i < num_pf_int - 2; i++)
> +	for (s32 i = 0; i < num_pf_int - 2; i++)
>   		wr32(hw, I40E_PFINT_DYN_CTLN(i), val);
>   
>   	/* Set the FIRSTQ_INDX field to 0x7FF in PFINT_LNKLSTx */
>   	val = eol << I40E_PFINT_LNKLST0_FIRSTQ_INDX_SHIFT;
>   	wr32(hw, I40E_PFINT_LNKLST0, val);
> -	for (i = 0; i < num_pf_int - 2; i++)
> +	for (s32 i = 0; i < num_pf_int - 2; i++)
>   		wr32(hw, I40E_PFINT_LNKLSTN(i), val);
>   	val = eol << I40E_VPINT_LNKLST0_FIRSTQ_INDX_SHIFT;
>   	for (i = 0; i < num_vfs; i++)
>   		wr32(hw, I40E_VPINT_LNKLST0(i), val);
> -	for (i = 0; i < num_vf_int - 2; i++)
> +	for (s32 i = 0; i < num_vf_int - 2; i++)
>   		wr32(hw, I40E_VPINT_LNKLSTN(i), val);
>   
>   	/* warn the HW of the coming Tx disables */

Re: [Intel-wired-lan] [PATCH] i40e: fix MMIO write access to an invalid page in i40e_clear_hw

[Kyungwook Boo]

On 25. 3. 6. 16:59, Przemek Kitszel wrote:
> On 3/6/25 06:25, Kyungwook Boo wrote:
>> In i40e_clear_hw(), when the device sends a specific input(e.g., 0),
>> an integer underflow in the num_{pf,vf}_int variables can occur,
>> leading to MMIO write access to an invalid page.
>>
>> To fix this, we change the type of the unsigned integer variables
>> num_{pf,vf}_int to signed integers. Additionally, in the for-loop where the
>> integer underflow occurs, we also change the type of the loop variable i to
>> a signed integer.
>>
>> Signed-off-by: Kyungwook Boo <bookyungwook@gmail.com>
>> Signed-off-by: Loktionov, Aleksandr <aleksandr.loktionov@intel.com>
> 
> when Alex said "make sure I signed too" he meant:
> "make sure the variable @i is signed too", not the Sign-off ;)
> 
> (please wait 24h for the next submission, and also put "iwl-next" after
> the "PATCH" word)
> 
>> Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
> 
> I didn't signed that either

Oh.. I totally misunderstood the comment.
I apologize for mistakenly adding the sign.

>> Link: https://lore.kernel.org/lkml/ffc91764-1142-4ba2-91b6-8c773f6f7095@gmail.com/T/
>> ---
>>   drivers/net/ethernet/intel/i40e/i40e_common.c | 10 +++++-----
>>   1 file changed, 5 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/intel/i40e/i40e_common.c b/drivers/net/ethernet/intel/i40e/i40e_common.c
>> index 370b4bddee44..9a73cb94dc5e 100644
>> --- a/drivers/net/ethernet/intel/i40e/i40e_common.c
>> +++ b/drivers/net/ethernet/intel/i40e/i40e_common.c
>> @@ -817,8 +817,8 @@ int i40e_pf_reset(struct i40e_hw *hw)
>>   void i40e_clear_hw(struct i40e_hw *hw)
>>   {
>>       u32 num_queues, base_queue;
>> -    u32 num_pf_int;
>> -    u32 num_vf_int;
>> +    s32 num_pf_int;
>> +    s32 num_vf_int;
>>       u32 num_vfs;
>>       u32 i, j;
> 
> It's fine to move the declaration of @i into the for loop, but
> you have to remove it here, otherwise it's shadowing, which we
> avoid.
> 
>>       u32 val;
>> @@ -848,18 +848,18 @@ void i40e_clear_hw(struct i40e_hw *hw)
>>       /* stop all the interrupts */
>>       wr32(hw, I40E_PFINT_ICR0_ENA, 0);
>>       val = 0x3 << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT;
>> -    for (i = 0; i < num_pf_int - 2; i++)
>> +    for (s32 i = 0; i < num_pf_int - 2; i++)
>>           wr32(hw, I40E_PFINT_DYN_CTLN(i), val);
>>         /* Set the FIRSTQ_INDX field to 0x7FF in PFINT_LNKLSTx */
>>       val = eol << I40E_PFINT_LNKLST0_FIRSTQ_INDX_SHIFT;
>>       wr32(hw, I40E_PFINT_LNKLST0, val);
>> -    for (i = 0; i < num_pf_int - 2; i++)
>> +    for (s32 i = 0; i < num_pf_int - 2; i++)
>>           wr32(hw, I40E_PFINT_LNKLSTN(i), val);
>>       val = eol << I40E_VPINT_LNKLST0_FIRSTQ_INDX_SHIFT;
>>       for (i = 0; i < num_vfs; i++)
>>           wr32(hw, I40E_VPINT_LNKLST0(i), val);
>> -    for (i = 0; i < num_vf_int - 2; i++)
>> +    for (s32 i = 0; i < num_vf_int - 2; i++)
>>           wr32(hw, I40E_VPINT_LNKLSTN(i), val);
>>         /* warn the HW of the coming Tx disables */
> 

Thank you for reviewing the patch.
I will correct the patch and resubmit it.

Best,
Kyungwook Boo

Re: [Intel-wired-lan] [PATCH] i40e: fix MMIO write access to an invalid page in i40e_clear_hw

[Loktionov, Aleksandr]

> -----Original Message-----
> From: Kyungwook Boo <bookyungwook@gmail.com>
> Sent: Thursday, March 6, 2025 6:26 AM
> To: Loktionov, Aleksandr <aleksandr.loktionov@intel.com>; Kitszel,
> Przemyslaw <przemyslaw.kitszel@intel.com>; Nguyen, Anthony L
> <anthony.l.nguyen@intel.com>
> Cc: intel-wired-lan@lists.osuosl.org; netdev@vger.kernel.org
> Subject: [PATCH] i40e: fix MMIO write access to an invalid page in
> i40e_clear_hw
Please follow the rules, add v2 to the patch

> 
> In i40e_clear_hw(), when the device sends a specific input(e.g., 0), an integer
> underflow in the num_{pf,vf}_int variables can occur, leading to MMIO write
> access to an invalid page.
> 
> To fix this, we change the type of the unsigned integer variables
> num_{pf,vf}_int to signed integers. Additionally, in the for-loop where the
> integer underflow occurs, we also change the type of the loop variable i to a
> signed integer.
Please do follow the linux kernel 

> 
> Signed-off-by: Kyungwook Boo <bookyungwook@gmail.com>
> Signed-off-by: Loktionov, Aleksandr <aleksandr.loktionov@intel.com>
> Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
> Link: https://lore.kernel.org/lkml/ffc91764-1142-4ba2-91b6-
> 8c773f6f7095@gmail.com/T/
> ---
Please up here versions history.

>  drivers/net/ethernet/intel/i40e/i40e_common.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/i40e/i40e_common.c
> b/drivers/net/ethernet/intel/i40e/i40e_common.c
> index 370b4bddee44..9a73cb94dc5e 100644
> --- a/drivers/net/ethernet/intel/i40e/i40e_common.c
> +++ b/drivers/net/ethernet/intel/i40e/i40e_common.c
> @@ -817,8 +817,8 @@ int i40e_pf_reset(struct i40e_hw *hw)  void
> i40e_clear_hw(struct i40e_hw *hw)  {
>  	u32 num_queues, base_queue;
> -	u32 num_pf_int;
> -	u32 num_vf_int;
> +	s32 num_pf_int;
> +	s32 num_vf_int;
>  	u32 num_vfs;
>  	u32 i, j;
What about this vars? Are they used?

>  	u32 val;
> @@ -848,18 +848,18 @@ void i40e_clear_hw(struct i40e_hw *hw)
>  	/* stop all the interrupts */
>  	wr32(hw, I40E_PFINT_ICR0_ENA, 0);
>  	val = 0x3 << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT;
> -	for (i = 0; i < num_pf_int - 2; i++)
> +	for (s32 i = 0; i < num_pf_int - 2; i++)
>  		wr32(hw, I40E_PFINT_DYN_CTLN(i), val);
> 
>  	/* Set the FIRSTQ_INDX field to 0x7FF in PFINT_LNKLSTx */
>  	val = eol << I40E_PFINT_LNKLST0_FIRSTQ_INDX_SHIFT;
>  	wr32(hw, I40E_PFINT_LNKLST0, val);
> -	for (i = 0; i < num_pf_int - 2; i++)
> +	for (s32 i = 0; i < num_pf_int - 2; i++)
>  		wr32(hw, I40E_PFINT_LNKLSTN(i), val);
>  	val = eol << I40E_VPINT_LNKLST0_FIRSTQ_INDX_SHIFT;
>  	for (i = 0; i < num_vfs; i++)
>  		wr32(hw, I40E_VPINT_LNKLST0(i), val);
> -	for (i = 0; i < num_vf_int - 2; i++)
> +	for (s32 i = 0; i < num_vf_int - 2; i++)
>  		wr32(hw, I40E_VPINT_LNKLSTN(i), val);
> 
>  	/* warn the HW of the coming Tx disables */
> --
> 2.25.1

Re: [Intel-wired-lan] [PATCH] i40e: fix MMIO write access to an invalid page in i40e_clear_hw

[Kyungwook Boo]

On 25. 3. 6. 20:13, Loktionov, Aleksandr wrote:
> 
> 
>> -----Original Message-----
>> From: Kyungwook Boo <bookyungwook@gmail.com>
>> Sent: Thursday, March 6, 2025 6:26 AM
>> To: Loktionov, Aleksandr <aleksandr.loktionov@intel.com>; Kitszel,
>> Przemyslaw <przemyslaw.kitszel@intel.com>; Nguyen, Anthony L
>> <anthony.l.nguyen@intel.com>
>> Cc: intel-wired-lan@lists.osuosl.org; netdev@vger.kernel.org
>> Subject: [PATCH] i40e: fix MMIO write access to an invalid page in
>> i40e_clear_hw
> Please follow the rules, add v2 to the patch

Hi, Loktionov,

Thank you for reviewing the patch.

Following your guidance, I will update the patch with the correct format and
also include v2.

>>
>> In i40e_clear_hw(), when the device sends a specific input(e.g., 0), an integer
>> underflow in the num_{pf,vf}_int variables can occur, leading to MMIO write
>> access to an invalid page.
>>
>> To fix this, we change the type of the unsigned integer variables
>> num_{pf,vf}_int to signed integers. Additionally, in the for-loop where the
>> integer underflow occurs, we also change the type of the loop variable i to a
>> signed integer.
> Please do follow the linux kernel 

If you are referring to the tone of the patch description, I will rewrite it in
the imperative mood.

>>
>> Signed-off-by: Kyungwook Boo <bookyungwook@gmail.com>
>> Signed-off-by: Loktionov, Aleksandr <aleksandr.loktionov@intel.com>
>> Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
>> Link: https://lore.kernel.org/lkml/ffc91764-1142-4ba2-91b6-
>> 8c773f6f7095@gmail.com/T/
>> ---
> Please up here versions history.

I have noted your request and will add the version history in the next update.

>>  drivers/net/ethernet/intel/i40e/i40e_common.c | 10 +++++-----
>>  1 file changed, 5 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/intel/i40e/i40e_common.c
>> b/drivers/net/ethernet/intel/i40e/i40e_common.c
>> index 370b4bddee44..9a73cb94dc5e 100644
>> --- a/drivers/net/ethernet/intel/i40e/i40e_common.c
>> +++ b/drivers/net/ethernet/intel/i40e/i40e_common.c
>> @@ -817,8 +817,8 @@ int i40e_pf_reset(struct i40e_hw *hw)  void
>> i40e_clear_hw(struct i40e_hw *hw)  {
>>  	u32 num_queues, base_queue;
>> -	u32 num_pf_int;
>> -	u32 num_vf_int;
>> +	s32 num_pf_int;
>> +	s32 num_vf_int;
>>  	u32 num_vfs;
>>  	u32 i, j;
> What about this vars? Are they used?

i, j are both used.
I think the relevant line to be considered is as follows:

if (val & I40E_PF_VT_PFALLOC_VALID_MASK && j >= i)
		num_vfs = (j - i) + 1;

After this, j is not used and 
i is used as index of several loops.

My current plan was to change only i to s32 since it is related to the bug.
However, i is also used outside the loop, as in the code above.

Should I proceed with the original plan, or would it be better to separate the
loop variable for clarity? I would appreciate your opinion on this.

>>  	u32 val;
>> @@ -848,18 +848,18 @@ void i40e_clear_hw(struct i40e_hw *hw)
>>  	/* stop all the interrupts */
>>  	wr32(hw, I40E_PFINT_ICR0_ENA, 0);
>>  	val = 0x3 << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT;
>> -	for (i = 0; i < num_pf_int - 2; i++)
>> +	for (s32 i = 0; i < num_pf_int - 2; i++)
>>  		wr32(hw, I40E_PFINT_DYN_CTLN(i), val);
>>
>>  	/* Set the FIRSTQ_INDX field to 0x7FF in PFINT_LNKLSTx */
>>  	val = eol << I40E_PFINT_LNKLST0_FIRSTQ_INDX_SHIFT;
>>  	wr32(hw, I40E_PFINT_LNKLST0, val);
>> -	for (i = 0; i < num_pf_int - 2; i++)
>> +	for (s32 i = 0; i < num_pf_int - 2; i++)
>>  		wr32(hw, I40E_PFINT_LNKLSTN(i), val);
>>  	val = eol << I40E_VPINT_LNKLST0_FIRSTQ_INDX_SHIFT;
>>  	for (i = 0; i < num_vfs; i++)
>>  		wr32(hw, I40E_VPINT_LNKLST0(i), val);
>> -	for (i = 0; i < num_vf_int - 2; i++)
>> +	for (s32 i = 0; i < num_vf_int - 2; i++)
>>  		wr32(hw, I40E_VPINT_LNKLSTN(i), val);
>>
>>  	/* warn the HW of the coming Tx disables */
>> --
>> 2.25.1

Best,
Kyungwook Boo