If the number of layer is greater than LTDC_MAX_LAYER, we can have
memory overflow when reading plane_fpsi[].
Signed-off-by: Yannick Fertré <yannick.fer...@st.com>
---
drivers/gpu/drm/stm/ltdc.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
index 32fd6a3..05bd4b6 100644
--- a/drivers/gpu/drm/stm/ltdc.c
+++ b/drivers/gpu/drm/stm/ltdc.c
@@ -1021,10 +1021,13 @@ static int ltdc_get_caps(struct drm_device *ddev)
struct ltdc_device *ldev = ddev->dev_private;
u32 bus_width_log2, lcr, gc2r;
- /* at least 1 layer must be managed */
+ /*
+ * at least 1 layer must be managed & the number of layers
+ * must not exceed LTDC_MAX_LAYER
+ */
lcr = reg_read(ldev->regs, LTDC_LCR);
- ldev->caps.nb_layers = max_t(int, lcr, 1);
+ ldev->caps.nb_layers = clamp((int)lcr, 1, LTDC_MAX_LAYER);
/* set data bus width */
gc2r = reg_read(ldev->regs, LTDC_GC2R);
--
2.7.4
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
