From 1fa81c270da4d8dffa84fcca448654a10ed0a5dc Mon Sep 17 00:00:00 2001
From: Sascha Hauer <s.hauer@pengutronix.de>
Date: Wed, 12 Jan 2011 13:02:28 +0100
Subject: [PATCH] dmaengine i.MX sdma: check sg entries for valid addresses and
lengths
This patch lets sdma_prep_slave_sg fail if the entries of an
sg list do not start on multiples of the word size or if the
lengths are not multiple of the word size.
Also, catch the previously unhandled DMA_SLAVE_BUSWIDTH_8_BYTES
and DMA_SLAVE_BUSWIDTH_UNDEFINED cases.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
drivers/dma/imx-sdma.c | 20 +++++++++++++++++---
1 file changed, 17 insertions(+), 3 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index c50305043f15f..8707723e36da7 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -925,10 +925,24 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
ret = -EINVAL;
goto err_out;
}
- if (sdmac->word_size == DMA_SLAVE_BUSWIDTH_4_BYTES)
+
+ switch (sdmac->word_size) {
+ case DMA_SLAVE_BUSWIDTH_4_BYTES:
bd->mode.command = 0;
- else
- bd->mode.command = sdmac->word_size;
+ if (count & 3 || sg->dma_address & 3)
+ return NULL;
+ break;
+ case DMA_SLAVE_BUSWIDTH_2_BYTES:
+ bd->mode.command = 2;
+ if (count & 1 || sg->dma_address & 1)
+ return NULL;
+ break;
+ case DMA_SLAVE_BUSWIDTH_1_BYTE:
+ bd->mode.command = 1;
+ break;
+ default:
+ return NULL;
+ }
param = BD_DONE | BD_EXTD | BD_CONT;
--
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