From 290b370657fe7373cb0f301355536bfc9900bcba Mon Sep 17 00:00:00 2001 From: Guangshuo Li Date: Wed, 8 Jul 2026 15:27:51 +0800 Subject: [PATCH] drm/amd/display: move connector state dereference after NULL check amdgpu_dm_connector_atomic_check() checks whether the old or new connector state returned by the atomic helpers is NULL before using those pointers. However, new_con_state is already dereferenced while initializing crtc, before the NULL check is reached. If drm_atomic_get_new_connector_state() returns NULL, the function can dereference the NULL pointer before the WARN_ON() check can handle it. Declare crtc first and initialize it only after the NULL check has succeeded. Fixes: 1e5e8d672fec ("drm/amd/display: Avoid a NULL pointer dereference") Signed-off-by: Guangshuo Li Reviewed-by: Mario Limonciello Link: https://patch.msgid.link/20260708072751.724400-1-lgs201920130244@gmail.com (ML: adjust for movement to amdgpu_dm_connector.c) Signed-off-by: Mario Limonciello Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_connector.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_connector.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_connector.c index f77af83ade39..dfce7f79dfe0 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_connector.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_connector.c @@ -2369,7 +2369,7 @@ amdgpu_dm_connector_atomic_check(struct drm_connector *conn, drm_atomic_get_new_connector_state(state, conn); struct drm_connector_state *old_con_state = drm_atomic_get_old_connector_state(state, conn); - struct drm_crtc *crtc = new_con_state->crtc; + struct drm_crtc *crtc; struct drm_crtc_state *new_crtc_state; struct amdgpu_dm_connector *aconn = to_amdgpu_dm_connector(conn); int ret; @@ -2385,6 +2385,7 @@ amdgpu_dm_connector_atomic_check(struct drm_connector *conn, return ret; } + crtc = new_con_state->crtc; if (!crtc) return 0;