From 958d104e3d40eef5148c402887138f6594ff7e1e Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 18 Dec 2015 15:18:08 +0100 Subject: [PATCH] netcp: fix regression in receive processing A cleanup patch I did was unfortunately wrong and introduced multiple serious bugs in the netcp rx processing, as indicated by these correct gcc warnings: drivers/net/ethernet/ti/netcp_core.c:776:14: warning: 'buf_ptr' may be used uninitialized in this function [-Wuninitialized] drivers/net/ethernet/ti/netcp_core.c:687:14: warning: 'ptr' may be used uninitialized in this function [-Wuninitialized] I have checked the patch once more and found that a call to get_pkt_info() accidentally got removed in netcp_free_rx_desc_chain, and netcp_process_one_rx_packet no longer retrieved the correct buffer length. This patch should fix all the known problems, but I did not test on real hardware. Signed-off-by: Arnd Bergmann Fixes: 899077791403 ("netcp: try to reduce type confusion in descriptors") Signed-off-by: David S. Miller --- drivers/net/ethernet/ti/netcp_core.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/ti/netcp_core.c b/drivers/net/ethernet/ti/netcp_core.c index 92d08eb262c2..c61d66d38634 100644 --- a/drivers/net/ethernet/ti/netcp_core.c +++ b/drivers/net/ethernet/ti/netcp_core.c @@ -582,6 +582,7 @@ static void netcp_free_rx_desc_chain(struct netcp_intf *netcp, unsigned int buf_len, dma_sz = sizeof(*ndesc); void *buf_ptr; u32 pad[2]; + u32 tmp; get_words(&dma_desc, 1, &desc->next_desc); @@ -591,6 +592,7 @@ static void netcp_free_rx_desc_chain(struct netcp_intf *netcp, dev_err(netcp->ndev_dev, "failed to unmap Rx desc\n"); break; } + get_pkt_info(&dma_buf, &tmp, &dma_desc, ndesc); get_pad_ptr(&buf_ptr, ndesc); dma_unmap_page(netcp->dev, dma_buf, PAGE_SIZE, DMA_FROM_DEVICE); __free_page(buf_ptr); @@ -637,6 +639,7 @@ static int netcp_process_one_rx_packet(struct netcp_intf *netcp) dma_addr_t dma_desc, dma_buff; struct netcp_packet p_info; struct sk_buff *skb; + u32 pad[2]; void *org_buf_ptr; dma_desc = knav_queue_pop(netcp->rx_queue, &dma_sz); @@ -650,7 +653,8 @@ static int netcp_process_one_rx_packet(struct netcp_intf *netcp) } get_pkt_info(&dma_buff, &buf_len, &dma_desc, desc); - get_pad_ptr(&org_buf_ptr, desc); + get_pad_info(&pad[0], &pad[1], &org_buf_len, desc); + org_buf_ptr = (void *)(uintptr_t)(pad[0] + ((u64)pad[1] << 32)); if (unlikely(!org_buf_ptr)) { dev_err(netcp->ndev_dev, "NULL bufptr in desc\n"); @@ -684,7 +688,7 @@ static int netcp_process_one_rx_packet(struct netcp_intf *netcp) } get_pkt_info(&dma_buff, &buf_len, &dma_desc, ndesc); - get_pad_ptr(ptr, ndesc); + get_pad_ptr(&ptr, ndesc); page = ptr; if (likely(dma_buff && buf_len && page)) { @@ -773,7 +777,7 @@ static void netcp_free_rx_buf(struct netcp_intf *netcp, int fdq) } get_org_pkt_info(&dma, &buf_len, desc); - get_pad_ptr(buf_ptr, desc); + get_pad_ptr(&buf_ptr, desc); if (unlikely(!dma)) { dev_err(netcp->ndev_dev, "NULL orig_buff in desc\n"); -- 2.11.0