[media] sh_vou: avoid going past arrays
Smatch reports two issues:
drivers/media/platform/sh_vou.c:670 vou_adjust_output() error: buffer overflow 'vou_scale_v_num' 3 <= 4
drivers/media/platform/sh_vou.c:670 vou_adjust_output() error: buffer overflow 'vou_scale_v_den' 3 <= 4
It seems that there's actually a bug here: the same var (idx) is used
as an index for vertical and horizontal scaling arrays. However,
there are 4 elements on the h arrays, and only 3 at the v ones.
On the first loop, it may select index 4 for the horizontal array.
In this case, if the second loop fails to select an index, the
code would keep using 4 for the vertical array, with is past of
the array sizes.
The intent here seems to use index 0, if the scale is not found.
So, use a separate var for the vertical index.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/platform/sh_vou.c b/drivers/media/platform/sh_vou.c
index 829e85c..8b799ba 100644
--- a/drivers/media/platform/sh_vou.c
+++ b/drivers/media/platform/sh_vou.c
@@ -600,7 +600,7 @@
{
unsigned int best_err = UINT_MAX, best = geo->in_width,
width_max, height_max, img_height_max;
- int i, idx = 0;
+ int i, idx_h = 0, idx_v = 0;
if (std & V4L2_STD_525_60) {
width_max = 858;
@@ -625,7 +625,7 @@
err = abs(found - geo->output.width);
if (err < best_err) {
best_err = err;
- idx = i;
+ idx_h = i;
best = found;
}
if (!err)
@@ -633,12 +633,12 @@
}
geo->output.width = best;
- geo->scale_idx_h = idx;
+ geo->scale_idx_h = idx_h;
if (geo->output.left + best > width_max)
geo->output.left = width_max - best;
pr_debug("%s(): W %u * %u/%u = %u\n", __func__, geo->in_width,
- vou_scale_h_num[idx], vou_scale_h_den[idx], best);
+ vou_scale_h_num[idx_h], vou_scale_h_den[idx_h], best);
best_err = UINT_MAX;
@@ -655,7 +655,7 @@
err = abs(found - geo->output.height);
if (err < best_err) {
best_err = err;
- idx = i;
+ idx_v = i;
best = found;
}
if (!err)
@@ -663,12 +663,12 @@
}
geo->output.height = best;
- geo->scale_idx_v = idx;
+ geo->scale_idx_v = idx_v;
if (geo->output.top + best > height_max)
geo->output.top = height_max - best;
pr_debug("%s(): H %u * %u/%u = %u\n", __func__, geo->in_height,
- vou_scale_v_num[idx], vou_scale_v_den[idx], best);
+ vou_scale_v_num[idx_v], vou_scale_v_den[idx_v], best);
}
static int sh_vou_s_fmt_vid_out(struct file *file, void *priv,