Re: [PATCH] staging: media: tegra-video: fix syncpoint leak in tegra20 channel init

[Mikko Perttunen]

On Sunday, July 26, 2026 7:04 PM Cong Nguyen wrote:
> tegra20_channel_host1x_syncpt_init() requests two host1x syncpoints. It
> stored the first one (mw ack) into chan->mw_ack_sp[0] and only then
> requested the second one (frame start). If the second request failed the
> function returned without releasing the first syncpoint, leaking it: the
> caller tegra_channel_init() bails out with a bare "return ret" on a
> syncpt init failure and does not run its free_syncpts error path (that
> path only covers failures after syncpoint init has fully succeeded), and
> the channel is subsequently torn down via the kfree()-only path, so
> nothing ever releases the orphaned syncpoint.
> 
> Release the already-acquired syncpoint on the error path, and only
> publish the syncpoints into the channel once both have been successfully
> requested, so chan->mw_ack_sp[0] never holds a released handle. This
> matches the handling in tegra210_channel_host1x_syncpt_init().
> 
> Fixes: 0e2c4117c351 ("staging: media: tegra-video: add CSI support for Tegra20 and Tegra30")
> Signed-off-by: Cong Nguyen <congnt264@xxxxxxxxx>
> ---
>  drivers/staging/media/tegra-video/tegra20.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/staging/media/tegra-video/tegra20.c b/drivers/staging/media/tegra-video/tegra20.c
> index e513e6ccb776..f8acb6834a0b 100644
> --- a/drivers/staging/media/tegra-video/tegra20.c
> +++ b/drivers/staging/media/tegra-video/tegra20.c
> @@ -429,12 +429,13 @@ static int tegra20_channel_host1x_syncpt_init(struct tegra_vi_channel *chan)
>  	if (!out_sp)
>  		return dev_err_probe(vi->dev, -EBUSY, "failed to request mw ack syncpoint\n");
>  
> -	chan->mw_ack_sp[0] = out_sp;
> -
>  	fs_sp = host1x_syncpt_request(&vi->client, HOST1X_SYNCPT_CLIENT_MANAGED);
> -	if (!fs_sp)
> +	if (!fs_sp) {
> +		host1x_syncpt_put(out_sp);
>  		return dev_err_probe(vi->dev, -EBUSY, "failed to request frame start syncpoint\n");
> +	}
>  
> +	chan->mw_ack_sp[0] = out_sp;
>  	chan->frame_start_sp[0] = fs_sp;
>  
>  	return 0;
> -- 
> 2.25.1
> 
> 

Thanks!

Reviewed-by: Mikko Perttunen <mperttunen@xxxxxxxxxx>