usb: typec: fix dereference before null check on adev

Pointer adev is being dereferenced before it is being sanity
checked with a null pointer check, hence it is possible for
a null pointer dereference to occur.  Fix this by dereferencing
adev only once it is null checked.

Detected by CoverityScan, CID#1471598 ("Dereference before null check")

Fixes: 8a37d87d72 ("usb: typec: Bus type for alternate modes")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Colin Ian King 2018-07-04 13:34:06 +01:00 committed by Greg Kroah-Hartman
parent 6f3fde684d
commit 9920184d78

View File

@ -51,7 +51,7 @@ static int typec_altmode_set_state(struct typec_altmode *adev, int state)
int typec_altmode_notify(struct typec_altmode *adev,
unsigned long conf, void *data)
{
bool is_port = is_typec_port(adev->dev.parent);
bool is_port;
struct altmode *altmode;
struct altmode *partner;
int ret;
@ -64,6 +64,7 @@ int typec_altmode_notify(struct typec_altmode *adev,
if (!altmode->partner)
return -ENODEV;
is_port = is_typec_port(adev->dev.parent);
partner = altmode->partner;
ret = typec_altmode_set_mux(is_port ? altmode : partner, (u8)conf);