[PATCH] dmaengine: xilinx_dma: check for invalid vdma interleaved parameters

[Peter Korsgaard <peter@korsgaard.com>]

The VDMA HSIZE register (corresponding to sgl[0].size) is only 16bit wide /
the VSIZE register (corresponding to numf) is only 13bit wide, so reject
requests not fitting within that rather than silently transferring too
little data.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
---
 drivers/dma/xilinx/xilinx_dma.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
index e40696f6f864..5eb51ae93e89 100644
--- a/drivers/dma/xilinx/xilinx_dma.c
+++ b/drivers/dma/xilinx/xilinx_dma.c
@@ -112,7 +112,9 @@
 
 /* Register Direct Mode Registers */
 #define XILINX_DMA_REG_VSIZE			0x0000
+#define XILINX_DMA_VSIZE_MASK			GENMASK(12, 0)
 #define XILINX_DMA_REG_HSIZE			0x0004
+#define XILINX_DMA_HSIZE_MASK			GENMASK(15, 0)
 
 #define XILINX_DMA_REG_FRMDLY_STRIDE		0x0008
 #define XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT	24
@@ -2050,6 +2052,10 @@ xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan,
 	if (!xt->numf || !xt->sgl[0].size)
 		return NULL;
 
+	if (xt->numf & ~XILINX_DMA_VSIZE_MASK ||
+	    xt->sgl[0].size & ~XILINX_DMA_HSIZE_MASK)
+		return NULL;
+
 	if (xt->frame_size != 1)
 		return NULL;
 
-- 
2.39.2