[PATCH iwl-next v4] ixgbe: Fix possible skb NULL pointer dereference

[PATCH iwl-next v4] ixgbe: Fix possible skb NULL pointer dereference

[Piotr Kwapulinski]

The commit c824125cbb18 ("ixgbe: Fix passing 0 to ERR_PTR in
ixgbe_run_xdp()") stopped utilizing the ERR-like macros for xdp status
encoding. Propagate this logic to the ixgbe_put_rx_buffer().

The commit also relaxed the skb NULL pointer check - caught by Smatch.
Restore this check.

Fixes: c824125cbb18 ("ixgbe: Fix passing 0 to ERR_PTR in ixgbe_run_xdp()")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Piotr Kwapulinski <piotr.kwapulinski@intel.com>
---
v1 -> v2
  Provide extra details in commit message for motivation of this patch
v2 -> v3
  Simplify the check condition
v3 -> v4
  Rebase to net-queue
---
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 7236f20..467f812 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -2105,7 +2105,7 @@ static void ixgbe_put_rx_buffer(struct ixgbe_ring *rx_ring,
 		/* hand second half of page back to the ring */
 		ixgbe_reuse_rx_page(rx_ring, rx_buffer);
 	} else {
-		if (!IS_ERR(skb) && IXGBE_CB(skb)->dma == rx_buffer->dma) {
+		if (skb && IXGBE_CB(skb)->dma == rx_buffer->dma) {
 			/* the page has been released from the ring */
 			IXGBE_CB(skb)->page_released = true;
 		} else {
-- 
2.43.0

Re: [PATCH iwl-next v4] ixgbe: Fix possible skb NULL pointer dereference

[Simon Horman]

On Fri, Jan 31, 2025 at 01:14:50PM +0100, Piotr Kwapulinski wrote:
> The commit c824125cbb18 ("ixgbe: Fix passing 0 to ERR_PTR in
> ixgbe_run_xdp()") stopped utilizing the ERR-like macros for xdp status
> encoding. Propagate this logic to the ixgbe_put_rx_buffer().
> 
> The commit also relaxed the skb NULL pointer check - caught by Smatch.
> Restore this check.
> 
> Fixes: c824125cbb18 ("ixgbe: Fix passing 0 to ERR_PTR in ixgbe_run_xdp()")
> Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
> Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
> Signed-off-by: Piotr Kwapulinski <piotr.kwapulinski@intel.com>
> ---
> v1 -> v2
>   Provide extra details in commit message for motivation of this patch
> v2 -> v3
>   Simplify the check condition
> v3 -> v4
>   Rebase to net-queue

Reviewed-by: Simon Horman <horms@kernel.org>

Re: [PATCH iwl-next v4] ixgbe: Fix possible skb NULL pointer dereference

[Simon Horman]

On Fri, Jan 31, 2025 at 01:14:50PM +0100, Piotr Kwapulinski wrote:
> The commit c824125cbb18 ("ixgbe: Fix passing 0 to ERR_PTR in
> ixgbe_run_xdp()") stopped utilizing the ERR-like macros for xdp status
> encoding. Propagate this logic to the ixgbe_put_rx_buffer().
> 
> The commit also relaxed the skb NULL pointer check - caught by Smatch.
> Restore this check.
> 
> Fixes: c824125cbb18 ("ixgbe: Fix passing 0 to ERR_PTR in ixgbe_run_xdp()")
> Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
> Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
> Signed-off-by: Piotr Kwapulinski <piotr.kwapulinski@intel.com>

Reviewed-by: Simon Horman <horms@kernel.org>

Re: [Intel-wired-lan] [PATCH iwl-next v4] ixgbe: Fix possible skb NULL pointer dereference

[Tony Nguyen]

On 1/31/2025 4:14 AM, Piotr Kwapulinski wrote:
> The commit c824125cbb18 ("ixgbe: Fix passing 0 to ERR_PTR in
> ixgbe_run_xdp()") stopped utilizing the ERR-like macros for xdp status
> encoding. Propagate this logic to the ixgbe_put_rx_buffer().
> 
> The commit also relaxed the skb NULL pointer check - caught by Smatch.
> Restore this check.
> 
> Fixes: c824125cbb18 ("ixgbe: Fix passing 0 to ERR_PTR in ixgbe_run_xdp()")
> Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
> Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
> Signed-off-by: Piotr Kwapulinski <piotr.kwapulinski@intel.com>
> ---
> v1 -> v2
>    Provide extra details in commit message for motivation of this patch
> v2 -> v3
>    Simplify the check condition
> v3 -> v4
>    Rebase to net-queue

Applied to net-queue; the target tree should have been updated as well 
(iwl-net).

I'm also adding in the Closes: for the report.

Closes: 
https://lore.kernel.org/intel-wired-lan/2c7d6c31-192a-4047-bd90-9566d0e14cc0@stanley.mountain/

Thanks,
Tony

> ---
>   drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> index 7236f20..467f812 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> @@ -2105,7 +2105,7 @@ static void ixgbe_put_rx_buffer(struct ixgbe_ring *rx_ring,
>   		/* hand second half of page back to the ring */
>   		ixgbe_reuse_rx_page(rx_ring, rx_buffer);
>   	} else {
> -		if (!IS_ERR(skb) && IXGBE_CB(skb)->dma == rx_buffer->dma) {
> +		if (skb && IXGBE_CB(skb)->dma == rx_buffer->dma) {
>   			/* the page has been released from the ring */
>   			IXGBE_CB(skb)->page_released = true;
>   		} else {

RE: [Intel-wired-lan] [PATCH iwl-next v4] ixgbe: Fix possible skb NULL pointer dereference

[Sanigani, SarithaX]

> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of
> Kwapulinski, Piotr
> Sent: 31 January 2025 17:45
> To: intel-wired-lan@lists.osuosl.org
> Cc: netdev@vger.kernel.org; dan.carpenter@linaro.org;
> yuehaibing@huawei.com; Fijalkowski, Maciej <maciej.fijalkowski@intel.com>;
> Kitszel, Przemyslaw <przemyslaw.kitszel@intel.com>; Kwapulinski, Piotr
> <piotr.kwapulinski@intel.com>
> Subject: [Intel-wired-lan] [PATCH iwl-next v4] ixgbe: Fix possible skb NULL
> pointer dereference
> 
> The commit c824125cbb18 ("ixgbe: Fix passing 0 to ERR_PTR in
> ixgbe_run_xdp()") stopped utilizing the ERR-like macros for xdp status
> encoding. Propagate this logic to the ixgbe_put_rx_buffer().
> 
> The commit also relaxed the skb NULL pointer check - caught by Smatch.
> Restore this check.
> 
> Fixes: c824125cbb18 ("ixgbe: Fix passing 0 to ERR_PTR in ixgbe_run_xdp()")
> Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
> Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
> Signed-off-by: Piotr Kwapulinski <piotr.kwapulinski@intel.com>
> ---
> v1 -> v2
>   Provide extra details in commit message for motivation of this patch
> v2 -> v3
>   Simplify the check condition
> v3 -> v4
>   Rebase to net-queue
> ---
>  drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 

Tested-by: Saritha Sanigani <sarithax.sanigani@intel.com> (A Contingent Worker at Intel)