i2c: smbus: kill memory leak on emulated and failed DMA SMBus xfers

If DMA safe memory was allocated, but the subsequent I2C transfer
fails the memory is leaked. Plug this leak.

Fixes: 8a77821e74d6 ("i2c: smbus: use DMA safe buffers for emulated SMBus transactions")
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c
index f3f6830..51970ba 100644 (file)
--- a/drivers/i2c/i2c-core-smbus.c
+++ b/drivers/i2c/i2c-core-smbus.c
@@ -465,15 +465,18 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr,
 
        status = i2c_transfer(adapter, msg, num);
        if (status < 0)
-               return status;
-       if (status != num)
-               return -EIO;
+               goto cleanup;
+       if (status != num) {
+               status = -EIO;
+               goto cleanup;
+       }
+       status = 0;
 
        /* Check PEC if last message is a read */
        if (i && (msg[num-1].flags & I2C_M_RD)) {
                status = i2c_smbus_check_pec(partial_pec, &msg[num-1]);
                if (status < 0)
-                       return status;
+                       goto cleanup;
        }
 
        if (read_write == I2C_SMBUS_READ)
@@ -499,12 +502,13 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr,
                        break;
                }
 
+cleanup:
        if (msg[0].flags & I2C_M_DMA_SAFE)
                kfree(msg[0].buf);
        if (msg[1].flags & I2C_M_DMA_SAFE)
                kfree(msg[1].buf);
 
-       return 0;
+       return status;
 }
 
 /**