[PATCH 4.9 053/128] media: dvb_frontend: ensure that inital front end status initialized

Greg Kroah-Hartman
2020-06-19T16:46:01Z

From: Colin Ian King <colin.king@canonical.com>

commit a9e4998073d49a762a154a6b48a332ec6cb8e6b1 upstream.

The fe_status variable s is not initialized meaning it can have any
random garbage status. This could be problematic if fe->ops.tune is
false as s is not updated by the call to fe->ops.tune() and a
subsequent check on the change status will using a garbage value.
Fix this by adding FE_NONE to the enum fe_status and initializing
s to this.

Detected by CoverityScan, CID#112887 ("Uninitialized scalar variable")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/media/dvb-core/dvb_frontend.c | 2 +-
include/uapi/linux/dvb/frontend.h | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/media/dvb-core/dvb_frontend.c
+++ b/drivers/media/dvb-core/dvb_frontend.c
@@ -629,7 +629,7 @@ static int dvb_frontend_thread(void *dat
struct dvb_frontend *fe = data;
struct dtv_frontend_properties *c = &fe->dtv_property_cache;
struct dvb_frontend_private *fepriv = fe->frontend_priv;
- enum fe_status s;
+ enum fe_status s = FE_NONE;
enum dvbfe_algo algo;
bool re_tune = false;
bool semheld = false;
--- a/include/uapi/linux/dvb/frontend.h
+++ b/include/uapi/linux/dvb/frontend.h
@@ -127,6 +127,7 @@ enum fe_sec_mini_cmd {
* to reset DiSEqC, tone and parameters
*/
enum fe_status {
+ FE_NONE = 0x00,
FE_HAS_SIGNAL = 0x01,
FE_HAS_CARRIER = 0x02,
FE_HAS_VITERBI = 0x04,