[PATCH 5.11 198/775] media: camss: Fix signedness bug in video_enum_fmt()

From: Greg Kroah-Hartman
Date: Mon Mar 01 2021 - 18:13:59 EST


From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit b00481bdca2d77fdae5f71517c09fd3b30eba57d ]

This test has a problem because we want to know if "k" is -1 or a
positive value less than "f->index". But the "f->index" variable is a
u32 so if "k == -1" then -1 gets type promoted to UINT_MAX which is
larger than "f->index". I've added an explicit test to check for -1.

Fixes: a3d412d4b9f3 ("media: Revert "media: camss: Make use of V4L2_CAP_IO_MC"")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Reviewed-by: Robert Foss <robert.foss@xxxxxxxxxx>
Reviewed-by: Andrey Konovalov <andrey.konovalov@xxxxxxxxxx>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/media/platform/qcom/camss/camss-video.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/platform/qcom/camss/camss-video.c b/drivers/media/platform/qcom/camss/camss-video.c
index bd9334af1c734..2fa3214775d58 100644
--- a/drivers/media/platform/qcom/camss/camss-video.c
+++ b/drivers/media/platform/qcom/camss/camss-video.c
@@ -579,7 +579,7 @@ static int video_enum_fmt(struct file *file, void *fh, struct v4l2_fmtdesc *f)
break;
}

- if (k < f->index)
+ if (k == -1 || k < f->index)
/*
* All the unique pixel formats matching the arguments
* have been enumerated (k >= 0 and f->index > 0), or
--
2.27.0