[PATCH 4.19 068/219] media: ti-vpe: vpe: fix a v4l2-compliance failure causing a kernel panic

Greg Kroah-Hartman
2019-12-29T17:41:33Z

From: Benoit Parrot <bparrot@ti.com>

[ Upstream commit a37980ac5be29b83da67bf7d571c6bd9f90f8e45 ]

v4l2-compliance fails with this message:

warn: v4l2-test-formats.cpp(717): \
TRY_FMT cannot handle an invalid pixelformat.
test VIDIOC_TRY_FMT: FAIL

This causes the following kernel panic:

Unable to handle kernel paging request at virtual address 56595561
pgd = ecd80e00
*pgd=00000000
Internal error: Oops: 205 [#1] PREEMPT SMP ARM
...
CPU: 0 PID: 930 Comm: v4l2-compliance Not tainted \
4.14.62-01715-gc8cd67f49a19 #1
Hardware name: Generic DRA72X (Flattened Device Tree)
task: ece44d80 task.stack: ecc6e000
PC is at __vpe_try_fmt+0x18c/0x2a8 [ti_vpe]
LR is at 0x8

Because the driver fails to properly check the 'num_planes' values for
proper ranges it ends up accessing out of bound data causing the kernel
panic.

Since this driver only handle single or dual plane pixel format, make
sure the provided value does not exceed 2 planes.

Signed-off-by: Benoit Parrot <bparrot@ti.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/platform/ti-vpe/vpe.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/platform/ti-vpe/vpe.c b/drivers/media/platform/ti-vpe/vpe.c
index ca9095b80309..54f0d9d3cc49 100644
--- a/drivers/media/platform/ti-vpe/vpe.c
+++ b/drivers/media/platform/ti-vpe/vpe.c
@@ -1646,7 +1646,7 @@ static int __vpe_try_fmt(struct vpe_ctx *ctx, struct v4l2_format *f,
&pix->height, MIN_H, MAX_H, H_ALIGN,
S_ALIGN);

- if (!pix->num_planes)
+ if (!pix->num_planes || pix->num_planes > 2)
pix->num_planes = fmt->coplanar ? 2 : 1;
else if (pix->num_planes > 1 && !fmt->coplanar)
pix->num_planes = 1;
--
2.20.1