i2c: ismt: use correct length when copy buffer

In block write mode, when encapsulating dma_buffer, first element is
'command', the rest is data buffer, so only copy actual data buffer
starting from block[1] with the size indicating by block[0].

Signed-off-by: Fan Du <fan.du@intel.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/i2c/busses/i2c-ismt.c b/drivers/i2c/busses/i2c-ismt.c
index 984492553e95..d9ee43c80cde 100644
--- a/drivers/i2c/busses/i2c-ismt.c
+++ b/drivers/i2c/busses/i2c-ismt.c
@@ -497,7 +497,7 @@ static int ismt_access(struct i2c_adapter *adap, u16 addr,
                         desc->wr_len_cmd = dma_size;
                         desc->control |= ISMT_DESC_BLK;
                         priv->dma_buffer[0] = command;
-                        memcpy(&priv->dma_buffer[1], &data->block[1], dma_size);
+                        memcpy(&priv->dma_buffer[1], &data->block[1], dma_size - 1);
                 } else {
                         /* Block Read */
                         dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA:  READ\n");
@@ -525,7 +525,7 @@ static int ismt_access(struct i2c_adapter *adap, u16 addr,
                         desc->wr_len_cmd = dma_size;
                         desc->control |= ISMT_DESC_I2C;
                         priv->dma_buffer[0] = command;
-                        memcpy(&priv->dma_buffer[1], &data->block[1], dma_size);
+                        memcpy(&priv->dma_buffer[1], &data->block[1], dma_size - 1);
                 } else {
                         /* i2c Block Read */
                         dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA:  READ\n");