media: tegra-video: Fix memory leak in __tegra_channel_try_format()

[ Upstream commit 43e5302 ]

The state object allocated by __v4l2_subdev_state_alloc() must be freed
with __v4l2_subdev_state_free() when it is no longer needed.

In __tegra_channel_try_format(), two error paths return directly after
v4l2_subdev_call() fails, without freeing the allocated 'sd_state'
object. This violates the requirement and causes a memory leak.

Fix this by introducing a cleanup label and using goto statements in the
error paths to ensure that __v4l2_subdev_state_free() is always called
before the function returns.

Fixes: 56f64b8 ("media: tegra-video: Use zero crop settings if subdev has no get_selection")
Fixes: 1ebaeb0 ("media: tegra-video: Add support for external sensor capture")
Cc: stable@vger.kernel.org
Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: GoodLuck612

drivers/staging/media/tegra-video/vi.c

@@ -440,7 +440,7 @@ static int __tegra_channel_try_format(struct tegra_vi_channel *chan,
 		.target = V4L2_SEL_TGT_CROP_BOUNDS,
 	};
 	struct v4l2_rect *try_crop;
-	int ret;
+	int ret = 0;
 
 	subdev = tegra_channel_get_remote_source_subdev(chan);
 	if (!subdev)
@@ -484,8 +484,10 @@ static int __tegra_channel_try_format(struct tegra_vi_channel *chan,
 		} else {
 			ret = v4l2_subdev_call(subdev, pad, get_selection,
 					       NULL, &sdsel);
-			if (ret)
-				return -EINVAL;
+			if (ret) {
+				ret = -EINVAL;
+				goto out_free;
+			}
 
 			try_crop->width = sdsel.r.width;
 			try_crop->height = sdsel.r.height;
@@ -497,14 +499,15 @@ static int __tegra_channel_try_format(struct tegra_vi_channel *chan,
 
 	ret = v4l2_subdev_call(subdev, pad, set_fmt, sd_state, &fmt);
 	if (ret < 0)
-		return ret;
+		goto out_free;
 
 	v4l2_fill_pix_format(pix, &fmt.format);
 	chan->vi->ops->vi_fmt_align(pix, fmtinfo->bpp);
 
+out_free:
 	__v4l2_subdev_state_free(sd_state);
 
-	return 0;
+	return ret;
 }
 
 static int tegra_channel_try_format(struct file *file, void *fh,