Commit 47021bed authored by Hongchen Zhang's avatar Hongchen Zhang
Browse files

net: stmmac: fix potential double free of dma descriptor resources 

LoongArch inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I733VA



--------------------------------

reset the dma descriptor related resource's pointer to NULL,otherwise
a potential double free problem may be triggered:
stmmac_open
  alloc_dma_desc_resources
  init_dma_desc_rings
  stmmac_hw_setup  (Failed)
    goto init_error;
  free_dma_desc_resources(priv);
  (DMA related resource pointer not reset to NULL)
...
stmmac_open
  alloc_dma_desc_resources
    alloc_dma_tx_desc_resources (Failed)
      free_dma_tx_desc_resources
      (Double free of tx_q->tx_skbuff_dma tx_q->tx_skbuff)

Signed-off-by: default avatarHongchen Zhang <zhanghongchen@loongson.cn>
Change-Id: Ie917b7402e86cbd1b253553c10ac4a5440e38c03
parent f3014d9a

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

+12 −0
Original line number Diff line number Diff line
@@ -1635,10 +1635,15 @@ static void free_dma_rx_desc_resources(struct stmmac_priv *priv) 
			dma_free_coherent(priv->device, priv->dma_rx_size *

					  sizeof(struct dma_extended_desc),

					  rx_q->dma_erx, rx_q->dma_rx_phy);

		rx_q->dma_rx = NULL;

		rx_q->dma_erx = NULL;



		kfree(rx_q->buf_pool);

		rx_q->buf_pool = NULL;



		if (rx_q->page_pool)

			page_pool_destroy(rx_q->page_pool);

		rx_q->page_pool = NULL;

	}

}
@@ -1675,8 +1680,15 @@ static void free_dma_tx_desc_resources(struct stmmac_priv *priv) 


		dma_free_coherent(priv->device, size, addr, tx_q->dma_tx_phy);



		tx_q->dma_etx = NULL;

		tx_q->dma_entx = NULL;

		tx_q->dma_tx = NULL;



		kfree(tx_q->tx_skbuff_dma);

		tx_q->tx_skbuff_dma = NULL;



		kfree(tx_q->tx_skbuff);

		tx_q->tx_skbuff = NULL;

	}

}