I2C block transfers can have a size up to 32 bytes. If starting close to the end of the address space, there may not be enough room to write that many bytes (on I2C block writes) or not enough bytes to be read (on I2C block reads.) In that case, we must shorten the transfer so that it does not exceed the address space. Signed-off-by: Jean Delvare <jdelvare@xxxxxxx> Cc: Guenter Roeck <linux@xxxxxxxxxxxx> Cc: Wolfram Sang <wsa@xxxxxxxxxxxxx> --- drivers/i2c/i2c-stub.c | 2 ++ 1 file changed, 2 insertions(+) --- linux-3.16-rc4.orig/drivers/i2c/i2c-stub.c 2014-07-12 11:56:30.933096483 +0200 +++ linux-3.16-rc4/drivers/i2c/i2c-stub.c 2014-07-13 17:01:02.891235856 +0200 @@ -220,6 +220,8 @@ static s32 stub_xfer(struct i2c_adapter * We ignore banks here, because banked chips don't use I2C * block transfers */ + if (data->block[0] > 256 - command) /* Avoid overrun */ + data->block[0] = 256 - command; len = data->block[0]; if (read_write == I2C_SMBUS_WRITE) { for (i = 0; i < len; i++) { -- Jean Delvare SUSE L3 Support -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html