From: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx>
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@xxxxxxxxxxxxxxx
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx>
---
This patch was added in v2.
---
drivers/staging/media/tegra-video/csi.c | 1 +
drivers/staging/media/tegra-video/csi.h | 2 +-
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/staging/media/tegra-video/csi.c b/drivers/staging/media/tegra-video/csi.c
index b26e44adb2be..6b59ef55c525 100644
--- a/drivers/staging/media/tegra-video/csi.c
+++ b/drivers/staging/media/tegra-video/csi.c
@@ -448,6 +448,7 @@ static int tegra_csi_channel_alloc(struct tegra_csi *csi,
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);
}
diff --git a/drivers/staging/media/tegra-video/csi.h b/drivers/staging/media/tegra-video/csi.h
index 4ee05a1785cf..6960ea2e3d36 100644
--- a/drivers/staging/media/tegra-video/csi.h
+++ b/drivers/staging/media/tegra-video/csi.h
@@ -56,7 +56,7 @@ 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 {
--
2.34.1
