[PATCH 4.14 032/125] media: tw5864: check status of tw5864_frameinterval_get

Greg Kroah-Hartman
2020-11-03T21:09:52Z

From: Tom Rix <trix@redhat.com>

[ Upstream commit 780d815dcc9b34d93ae69385a8465c38d423ff0f ]

clang static analysis reports this problem

tw5864-video.c:773:32: warning: The left expression of the compound
assignment is an uninitialized value.
The computed value will also be garbage
fintv->stepwise.max.numerator *= std_max_fps;
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^

stepwise.max is set with frameinterval, which comes from

ret = tw5864_frameinterval_get(input, &frameinterval);
fintv->stepwise.step = frameinterval;
fintv->stepwise.min = frameinterval;
fintv->stepwise.max = frameinterval;
fintv->stepwise.max.numerator *= std_max_fps;

When tw5864_frameinterval_get() fails, frameinterval is not
set. So check the status and fix another similar problem.

Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/pci/tw5864/tw5864-video.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/media/pci/tw5864/tw5864-video.c b/drivers/media/pci/tw5864/tw5864-video.c
index ee1230440b397..02258685800a7 100644
--- a/drivers/media/pci/tw5864/tw5864-video.c
+++ b/drivers/media/pci/tw5864/tw5864-video.c
@@ -776,6 +776,9 @@ static int tw5864_enum_frameintervals(struct file *file, void *priv,
fintv->type = V4L2_FRMIVAL_TYPE_STEPWISE;

ret = tw5864_frameinterval_get(input, &frameinterval);
+ if (ret)
+ return ret;
+
fintv->stepwise.step = frameinterval;
fintv->stepwise.min = frameinterval;
fintv->stepwise.max = frameinterval;
@@ -794,6 +797,9 @@ static int tw5864_g_parm(struct file *file, void *priv,
cp->capability = V4L2_CAP_TIMEPERFRAME;

ret = tw5864_frameinterval_get(input, &cp->timeperframe);
+ if (ret)
+ return ret;
+
cp->timeperframe.numerator *= input->frame_interval;
cp->capturemode = 0;
cp->readbuffers = 2;
--
2.27.0