6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Evgenii Burenchev [ Upstream commit 98cad4bd1443975d972f4c7f705980da03722a22 ] amdgpu_dm_plane_drm_plane_reset() frees the old state before allocating a new one. If kzalloc() fails, the function returns without updating the state pointer, leaving a dangling pointer to already freed memory. Fix this by allocating the new state first. On allocation failure, the old state remains untouched and the function safely returns. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 5d945cbcd4b1 ("drm/amd/display: Create a file dedicated to planes") Signed-off-by: Evgenii Burenchev Reviewed-by: Mario Limonciello (AMD) Link: https://patch.msgid.link/20260629090435.9729-3-evg28bur@yandex.ru [adjust for movement around current amd-staging-drm-next] Signed-off-by: Mario Limonciello Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c index 175e4b11b43bd..54e4b48bd78a6 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c @@ -1446,17 +1446,15 @@ static const struct drm_plane_helper_funcs dm_primary_plane_helper_funcs = { static void amdgpu_dm_plane_drm_plane_reset(struct drm_plane *plane) { - struct dm_plane_state *amdgpu_state = NULL; - - if (plane->state) - plane->funcs->atomic_destroy_state(plane, plane->state); + struct dm_plane_state *amdgpu_state; amdgpu_state = kzalloc(sizeof(*amdgpu_state), GFP_KERNEL); - WARN_ON(amdgpu_state == NULL); - if (!amdgpu_state) return; + if (plane->state) + plane->funcs->atomic_destroy_state(plane, plane->state); + __drm_atomic_helper_plane_reset(plane, &amdgpu_state->base); amdgpu_state->degamma_tf = AMDGPU_TRANSFER_FUNCTION_DEFAULT; amdgpu_state->hdr_mult = AMDGPU_HDR_MULT_DEFAULT; -- 2.53.0