From 85aec73d595b8847f9c4ea571deb127913f0d508 Mon Sep 17 00:00:00 2001 From: Ivan Vecera Date: Wed, 6 Nov 2013 14:02:36 +0100 Subject: [PATCH] tg3: avoid double-freeing of rx data memory If build_skb fails the memory associated with the ring buffer is freed but the ri->data member is not zeroed in this case. This causes a double-free of this memory in tg3_free_rings->... path. The patch moves this block after setting ri->data to NULL. It would be nice to fix this bug also in stable >= v3.4 trees. Cc: Nithin Nayak Sujir Cc: Michael Chan Signed-off-by: Ivan Vecera Acked-by: Michael Chan Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/tg3.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c index 819d87c281bf..00c5be8c55b8 100644 --- a/drivers/net/ethernet/broadcom/tg3.c +++ b/drivers/net/ethernet/broadcom/tg3.c @@ -6862,12 +6862,6 @@ static int tg3_rx(struct tg3_napi *tnapi, int budget) pci_unmap_single(tp->pdev, dma_addr, skb_size, PCI_DMA_FROMDEVICE); - skb = build_skb(data, frag_size); - if (!skb) { - tg3_frag_free(frag_size != 0, data); - goto drop_it_no_recycle; - } - skb_reserve(skb, TG3_RX_OFFSET(tp)); /* Ensure that the update to the data happens * after the usage of the old DMA mapping. */ @@ -6875,6 +6869,12 @@ static int tg3_rx(struct tg3_napi *tnapi, int budget) ri->data = NULL; + skb = build_skb(data, frag_size); + if (!skb) { + tg3_frag_free(frag_size != 0, data); + goto drop_it_no_recycle; + } + skb_reserve(skb, TG3_RX_OFFSET(tp)); } else { tg3_recycle_rx(tnapi, tpr, opaque_key, desc_idx, *post_ptr); -- 2.20.1