From: Dan Carpenter dan.carpenter@oracle.com
commit 690b2549b19563ec5ad53e5c82f6a944d910086e upstream.
The "data->block[0]" variable comes from the user and is a number between 0-255. It needs to be capped to prevent writing beyond the end of dma_buffer[].
Fixes: 5e9a97b1f449 ("i2c: ismt: Adding support for I2C_SMBUS_BLOCK_PROC_CALL") Reported-and-tested-by: Zheyu Ma zheyuma97@gmail.com Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Reviewed-by: Mika Westerberg mika.westerberg@linux.intel.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/i2c/busses/i2c-ismt.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/drivers/i2c/busses/i2c-ismt.c +++ b/drivers/i2c/busses/i2c-ismt.c @@ -528,6 +528,9 @@ static int ismt_access(struct i2c_adapte
case I2C_SMBUS_BLOCK_PROC_CALL: dev_dbg(dev, "I2C_SMBUS_BLOCK_PROC_CALL\n"); + if (data->block[0] > I2C_SMBUS_BLOCK_MAX) + return -EINVAL; + dma_size = I2C_SMBUS_BLOCK_MAX; desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, 1); desc->wr_len_cmd = data->block[0] + 1;