As reported by Coverity, the logic at tpg_precalculate_line()
blindly rescales the buffer even when scaled_witdh is equal to
zero. If this ever happens, this will cause a division by zero.
Instead, add a WARN_ON_ONCE() to trigger such cases and return
without doing any precalculation.
Fixes: 63881df94d3e ("[media] vivid: add the Test Pattern Generator")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
---
drivers/media/common/v4l2-tpg/v4l2-tpg-core.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c
index c86343a4d0bf..940bfbf275ce 100644
--- a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c
+++ b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c
@@ -1795,6 +1795,9 @@ static void tpg_precalculate_line(struct tpg_data *tpg)
unsigned p;
unsigned x;
+ if (WARN_ON_ONCE(!tpg->src_width || !tpg->scaled_width))
+ return;
+
switch (tpg->pattern) {
case TPG_PAT_GREEN:
contrast = TPG_COLOR_100_RED;
--
2.47.0
