[PATCH] drm/panel: ilitek-ili9881c: fix attach failure cleanup

From: Icenowy Zheng
Date: Wed Dec 30 2020 - 15:45:41 EST


When mipi_dsi_attach() fails (e.g. got a -EPROBE_DEFER), the panel should
be removed, otherwise a pointer to it will be kept and then lead to
use-after-free when DRM panel codes are called (e.g. the panel is probed
again).

Fix this by adding cleanup code after mipi_dsi_attach() failure.

Fixes: 26aec25593c2 ("drm/panel: Add Ilitek ILI9881c panel driver")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Icenowy Zheng <icenowy@xxxxxxx>
---
drivers/gpu/drm/panel/panel-ilitek-ili9881c.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/panel/panel-ilitek-ili9881c.c b/drivers/gpu/drm/panel/panel-ilitek-ili9881c.c
index 0145129d7c66..22f2268f00f7 100644
--- a/drivers/gpu/drm/panel/panel-ilitek-ili9881c.c
+++ b/drivers/gpu/drm/panel/panel-ilitek-ili9881c.c
@@ -674,7 +674,13 @@ static int ili9881c_dsi_probe(struct mipi_dsi_device *dsi)
dsi->format = MIPI_DSI_FMT_RGB888;
dsi->lanes = 4;

- return mipi_dsi_attach(dsi);
+ ret = mipi_dsi_attach(dsi);
+ if (ret < 0) {
+ drm_panel_remove(&ctx->panel);
+ return ret;
+ }
+
+ return 0;
}

static int ili9881c_dsi_remove(struct mipi_dsi_device *dsi)
--
2.28.0