The wx_rx_buffer structure contained two DMA address fields: 'dma' and 'page_dma'. However, only 'page_dma' was actually initialized and used to program the Rx descriptor. But 'dma' was uninitialized and used in some paths.
This could lead to undefined behavior, including DMA errors or use-after-free, if the uninitialized 'dma' was used. Althrough such error has not yet occurred, it is worth fixing in the code.
Fixes: 3c47e8ae113a ("net: libwx: Support to receive packets in NAPI") Cc: stable@vger.kernel.org Signed-off-by: Jiawen Wu jiawenwu@trustnetic.com --- drivers/net/ethernet/wangxun/libwx/wx_lib.c | 4 ++-- drivers/net/ethernet/wangxun/libwx/wx_type.h | 1 - 2 files changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/wangxun/libwx/wx_lib.c b/drivers/net/ethernet/wangxun/libwx/wx_lib.c index 7e3d7fb61a52..c91487909811 100644 --- a/drivers/net/ethernet/wangxun/libwx/wx_lib.c +++ b/drivers/net/ethernet/wangxun/libwx/wx_lib.c @@ -307,7 +307,7 @@ static bool wx_alloc_mapped_page(struct wx_ring *rx_ring, return false; dma = page_pool_get_dma_addr(page);
- bi->page_dma = dma; + bi->dma = dma; bi->page = page; bi->page_offset = 0;
@@ -344,7 +344,7 @@ void wx_alloc_rx_buffers(struct wx_ring *rx_ring, u16 cleaned_count) DMA_FROM_DEVICE);
rx_desc->read.pkt_addr = - cpu_to_le64(bi->page_dma + bi->page_offset); + cpu_to_le64(bi->dma + bi->page_offset);
rx_desc++; bi++; diff --git a/drivers/net/ethernet/wangxun/libwx/wx_type.h b/drivers/net/ethernet/wangxun/libwx/wx_type.h index c363379126c0..f5a8ce681a68 100644 --- a/drivers/net/ethernet/wangxun/libwx/wx_type.h +++ b/drivers/net/ethernet/wangxun/libwx/wx_type.h @@ -998,7 +998,6 @@ struct wx_tx_buffer { struct wx_rx_buffer { struct sk_buff *skb; dma_addr_t dma; - dma_addr_t page_dma; struct page *page; unsigned int page_offset; };
On Wed, Jul 09, 2025 at 02:40:24PM +0800, Jiawen Wu wrote:
The wx_rx_buffer structure contained two DMA address fields: 'dma' and 'page_dma'. However, only 'page_dma' was actually initialized and used to program the Rx descriptor. But 'dma' was uninitialized and used in some paths.
This could lead to undefined behavior, including DMA errors or use-after-free, if the uninitialized 'dma' was used. Althrough such error has not yet occurred, it is worth fixing in the code.
Fixes: 3c47e8ae113a ("net: libwx: Support to receive packets in NAPI") Cc: stable@vger.kernel.org Signed-off-by: Jiawen Wu jiawenwu@trustnetic.com
Reviewed-by: Simon Horman horms@kernel.org
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