media: v4l2-rect.h: fix v4l2_rect_map_inside() top/left adjustments
authorHelen Koike <helen.koike@collabora.com>
Tue, 17 Dec 2019 20:00:22 +0000 (21:00 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 11 Feb 2020 12:35:14 +0000 (04:35 -0800)
commit9cbcbfc67b256a33bc063764407b23946f0ee427
tree545c9d13be6d58b2fa5a33051de3de1c3ecfb51a
parent965ccdedf1bfdea9f41509d1b63969432976337a
media: v4l2-rect.h: fix v4l2_rect_map_inside() top/left adjustments

commit f51e50db4c20d46930b33be3f208851265694f3e upstream.

boundary->width and boundary->height are sizes relative to
boundary->left and boundary->top coordinates, but they were not being
taken into consideration to adjust r->left and r->top, leading to the
following error:

Consider the follow as initial values for boundary and r:

struct v4l2_rect boundary = {
.left = 100,
.top = 100,
.width = 800,
.height = 600,
}

struct v4l2_rect r = {
.left = 0,
.top = 0,
.width = 1920,
.height = 960,
}

calling v4l2_rect_map_inside(&r, &boundary) was modifying r to:

r = {
.left = 0,
.top = 0,
.width = 800,
.height = 600,
}

Which is wrongly outside the boundary rectangle, because:

v4l2_rect_set_max_size(r, boundary); // r->width = 800, r->height = 600
...
if (r->left + r->width > boundary->width) // true
r->left = boundary->width - r->width; // r->left = 800 - 800
if (r->top + r->height > boundary->height) // true
r->top = boundary->height - r->height; // r->height = 600 - 600

Fix this by considering top/left coordinates from boundary.

Fixes: ac49de8c49d7 ("[media] v4l2-rect.h: new header with struct v4l2_rect helper functions")
Signed-off-by: Helen Koike <helen.koike@collabora.com>
Cc: <stable@vger.kernel.org> # for v4.7 and up
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
include/media/v4l2-rect.h