diff mbox series

[net,v1,1/2] iavf: Fix handling of dummy receive descriptors

Message ID 20220625003302.3501801-2-jesse.brandeburg@intel.com
State Accepted
Delegated to: Anthony Nguyen
Headers show
Series fix bug and remove code | expand

Commit Message

Jesse Brandeburg June 25, 2022, 12:33 a.m. UTC 
From: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>

Fix memory leak caused by not handling dummy receive descriptor properly.
iavf_get_rx_buffer now sets the rx_buffer return value for dummy receive
descriptors. Without this patch, when the hardware writes a dummy
descriptor, iavf would not free the page allocated for the previous receive
buffer. This is an unlikely event but can still happen.

[Jesse: massaged commit message]

Fixes: efa14c398582 ("iavf: allow null RX descriptors")
Signed-off-by: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
---
 drivers/net/ethernet/intel/iavf/iavf_txrx.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

Comments

Jankowski, Konrad0 July 5, 2022, 10:03 a.m. UTC | #1 
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of
> Jesse Brandeburg
> Sent: Saturday, June 25, 2022 2:33 AM
> To: intel-wired-lan@lists.osuosl.org
> Cc: Patynowski, PrzemyslawX <przemyslawx.patynowski@intel.com>;
> Brandeburg, Jesse <jesse.brandeburg@intel.com>
> Subject: [Intel-wired-lan] [PATCH net v1 1/2] iavf: Fix handling of dummy
> receive descriptors
> 
> From: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>
> 
> Fix memory leak caused by not handling dummy receive descriptor properly.
> iavf_get_rx_buffer now sets the rx_buffer return value for dummy receive
> descriptors. Without this patch, when the hardware writes a dummy
> descriptor, iavf would not free the page allocated for the previous receive
> buffer. This is an unlikely event but can still happen.
> 
> [Jesse: massaged commit message]
> 
> Fixes: efa14c398582 ("iavf: allow null RX descriptors")
> Signed-off-by: Przemyslaw Patynowski
> <przemyslawx.patynowski@intel.com>
> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
> ---
>  drivers/net/ethernet/intel/iavf/iavf_txrx.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/iavf/iavf_txrx.c
> b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
> index 7bf8c25dc824..06d18797d25a 100644
> --- a/drivers/net/ethernet/intel/iavf/iavf_txrx.c
> +++ b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
> @@ -1285,11 +1285,10 @@ static struct iavf_rx_buffer

Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
diff mbox series

Patch

diff --git a/drivers/net/ethernet/intel/iavf/iavf_txrx.c b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
index 7bf8c25dc824..06d18797d25a 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_txrx.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
@@ -1285,11 +1285,10 @@  static struct iavf_rx_buffer *iavf_get_rx_buffer(struct iavf_ring *rx_ring,
 {
 	struct iavf_rx_buffer *rx_buffer;
 
-	if (!size)
-		return NULL;
-
 	rx_buffer = &rx_ring->rx_bi[rx_ring->next_to_clean];
 	prefetchw(rx_buffer->page);
+	if (!size)
+		return rx_buffer;
 
 	/* we are reusing so sync this buffer for CPU use */
 	dma_sync_single_range_for_cpu(rx_ring->dev,