mei: bus: check if the device is enabled before data transfer

commit 15c13dfcad883a1e76b714480fb27be96247fd82 upstream.

The bus data transfer interface was missing the check if the device is
in enabled state, this may lead to stack corruption during link reset.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c
index 0b05aa9387996484759e748831eba5304ac3a409..1a173d0af694407312b5a45bbe0d0bde70e0d12b 100644 (file)
--- a/drivers/misc/mei/bus.c
+++ b/drivers/misc/mei/bus.c
@@ -53,6 +53,11 @@ ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
        bus = cl->dev;
 
        mutex_lock(&bus->device_lock);
+       if (bus->dev_state != MEI_DEV_ENABLED) {
+               rets = -ENODEV;
+               goto out;
+       }
+
        if (!mei_cl_is_connected(cl)) {
                rets = -ENODEV;
                goto out;
@@ -109,6 +114,10 @@ ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
        bus = cl->dev;
 
        mutex_lock(&bus->device_lock);
+       if (bus->dev_state != MEI_DEV_ENABLED) {
+               rets = -ENODEV;
+               goto out;
+       }
 
        cb = mei_cl_read_cb(cl, NULL);
        if (cb)