From: Ivan Vecera Date: Wed, 6 Nov 2013 13:02:36 +0000 (+0100) Subject: tg3: avoid double-freeing of rx data memory X-Git-Tag: v4.9.8~7477^2~35 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=85aec73d595b8847f9c4ea571deb127913f0d508;p=platform%2Fkernel%2Flinux-rpi3.git 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 --- diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c index 819d87c..00c5be8 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);