From: Luca Ceresoli luca.ceresoli@bootlin.com
commit 10b5ce6743c839fa75336042c64e2479caec9430 upstream.
chan->mipi takes the return value of tegra_mipi_request() which can be a valid pointer or an error. However chan->mipi is checked in several places, including error-cleanup code in tegra_csi_channels_cleanup(), as 'if (chan->mipi)', which suggests the initial intent was that chan->mipi should be either NULL or a valid pointer, never an error. As a consequence, cleanup code in case of tegra_mipi_request() errors would dereference an invalid pointer.
Fix by ensuring chan->mipi always contains either NULL or a void pointer.
Also add that to the documentation.
Fixes: 523c857e34ce ("media: tegra-video: Add CSI MIPI pads calibration") Cc: stable@vger.kernel.org Reported-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Luca Ceresoli luca.ceresoli@bootlin.com Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/staging/media/tegra-video/csi.c | 1 + drivers/staging/media/tegra-video/csi.h | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/staging/media/tegra-video/csi.c +++ b/drivers/staging/media/tegra-video/csi.c @@ -435,6 +435,7 @@ static int tegra_csi_channel_alloc(struc chan->mipi = tegra_mipi_request(csi->dev, node); if (IS_ERR(chan->mipi)) { ret = PTR_ERR(chan->mipi); + chan->mipi = NULL; dev_err(csi->dev, "failed to get mipi device: %d\n", ret); }
--- a/drivers/staging/media/tegra-video/csi.h +++ b/drivers/staging/media/tegra-video/csi.h @@ -50,7 +50,7 @@ struct tegra_csi; * @framerate: active framerate for TPG * @h_blank: horizontal blanking for TPG active format * @v_blank: vertical blanking for TPG active format - * @mipi: mipi device for corresponding csi channel pads + * @mipi: mipi device for corresponding csi channel pads, or NULL if not applicable (TPG, error) * @pixel_rate: active pixel rate from the sensor on this channel */ struct tegra_csi_channel {