From: Jean Delvare Date: Sun, 13 Jul 2014 15:17:17 +0000 (+0200) Subject: i2c: stub: Avoid an array overrun on I2C block transfers X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=0f6ba0d15f43e2be8cae9e3906aa03fcfe231e5b;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git i2c: stub: Avoid an array overrun on I2C block transfers 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 Reviewed-by: Guenter Roeck Signed-off-by: Wolfram Sang --- diff --git a/drivers/i2c/i2c-stub.c b/drivers/i2c/i2c-stub.c index e815c6067ff3..d241aa295d96 100644 --- a/drivers/i2c/i2c-stub.c +++ b/drivers/i2c/i2c-stub.c @@ -226,6 +226,8 @@ static s32 stub_xfer(struct i2c_adapter *adap, u16 addr, unsigned short flags, * 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++) {