summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJohan Hovold <johan@kernel.org>2017-01-12 14:56:16 +0100
committerJohan Hovold <johan@kernel.org>2017-01-16 16:38:56 +0100
commit36356a669eddb32917fc4b5c2b9b8bf80ede69de (patch)
treeb22ebd4ccc8ff200b9fca70f9876f948d7bbee51
parent750acdd781cf7e97c8c60d2ff5053dd4b12bbc84 (diff)
USB: serial: mct_u232: fix modem-status error handling
Make sure to detect short control-message transfers so that errors are logged when reading the modem status at open. Note that while this also avoids initialising the modem status using uninitialised heap data, these bits could not leak to user space as they are currently not used. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Johan Hovold <johan@kernel.org>
-rw-r--r--drivers/usb/serial/mct_u232.c6
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/usb/serial/mct_u232.c b/drivers/usb/serial/mct_u232.c
index 885655315de1..edbc81f205c2 100644
--- a/drivers/usb/serial/mct_u232.c
+++ b/drivers/usb/serial/mct_u232.c
@@ -322,8 +322,12 @@ static int mct_u232_get_modem_stat(struct usb_serial_port *port,
MCT_U232_GET_REQUEST_TYPE,
0, 0, buf, MCT_U232_GET_MODEM_STAT_SIZE,
WDR_TIMEOUT);
- if (rc < 0) {
+ if (rc < MCT_U232_GET_MODEM_STAT_SIZE) {
dev_err(&port->dev, "Get MODEM STATus failed (error = %d)\n", rc);
+
+ if (rc >= 0)
+ rc = -EIO;
+
*msr = 0;
} else {
*msr = buf[0];