The mma9551 functions that read/write word arrays from the device have a limit for the buffer size given by the device specifications.
Check that the requested buffer length is within required limits when transferring word arrays. This will prevent buffer overrun in the mma9551_read/write_*_words functions and also in the mma9551_transfer call when writing into the MBOX response/request structure. Signed-off-by: Irina Tirdea <[email protected]> Reported-by: Hartmut Knaack <[email protected]> --- drivers/iio/accel/mma9551_core.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/drivers/iio/accel/mma9551_core.c b/drivers/iio/accel/mma9551_core.c index 7f55a6d..c6d5a3a 100644 --- a/drivers/iio/accel/mma9551_core.c +++ b/drivers/iio/accel/mma9551_core.c @@ -389,7 +389,12 @@ int mma9551_read_config_words(struct i2c_client *client, u8 app_id, { int ret, i; int len_words = len / sizeof(u16); - __be16 be_buf[MMA9551_MAX_MAILBOX_DATA_REGS]; + __be16 be_buf[MMA9551_MAX_MAILBOX_DATA_REGS / 2]; + + if (len_words > ARRAY_SIZE(be_buf)) { + dev_err(&client->dev, "Invalid buffer size %d\n", len); + return -EINVAL; + } ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_CONFIG, reg, NULL, 0, (u8 *) be_buf, len); @@ -424,7 +429,12 @@ int mma9551_read_status_words(struct i2c_client *client, u8 app_id, { int ret, i; int len_words = len / sizeof(u16); - __be16 be_buf[MMA9551_MAX_MAILBOX_DATA_REGS]; + __be16 be_buf[MMA9551_MAX_MAILBOX_DATA_REGS / 2]; + + if (len_words > ARRAY_SIZE(be_buf)) { + dev_err(&client->dev, "Invalid buffer size %d\n", len); + return -EINVAL; + } ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_STATUS, reg, NULL, 0, (u8 *) be_buf, len); @@ -459,7 +469,12 @@ int mma9551_write_config_words(struct i2c_client *client, u8 app_id, { int i; int len_words = len / sizeof(u16); - __be16 be_buf[MMA9551_MAX_MAILBOX_DATA_REGS]; + __be16 be_buf[(MMA9551_MAX_MAILBOX_DATA_REGS - 1) / 2]; + + if (len_words > ARRAY_SIZE(be_buf)) { + dev_err(&client->dev, "Invalid buffer size %d\n", len); + return -EINVAL; + } for (i = 0; i < len_words; i++) be_buf[i] = cpu_to_be16(buf[i]); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
