[PATCH 4.14 075/109] drm/amdgpu:fix virtual dce bug

From: Greg Kroah-Hartman
Date: Fri Mar 16 2018 - 11:37:18 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Monk Liu <Monk.Liu@xxxxxxx>


[ Upstream commit 129d65c18ecfb249aceb540c31fdaf79bd5a11ff ]

this fix the issue that access memory after freed
after driver unloaded.

Signed-off-by: Monk Liu <Monk.Liu@xxxxxxx>
Acked-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/dce_virtual.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/amd/amdgpu/dce_virtual.c
+++ b/drivers/gpu/drm/amd/amdgpu/dce_virtual.c
@@ -437,6 +437,8 @@ static int dce_virtual_sw_fini(void *han
drm_kms_helper_poll_fini(adev->ddev);

drm_mode_config_cleanup(adev->ddev);
+ /* clear crtcs pointer to avoid dce irq finish routine access freed data */
+ memset(adev->mode_info.crtcs, 0, sizeof(adev->mode_info.crtcs[0]) * AMDGPU_MAX_CRTCS);
adev->mode_info.mode_config_initialized = false;
return 0;
}
@@ -723,7 +725,7 @@ static void dce_virtual_set_crtc_vblank_
int crtc,
enum amdgpu_interrupt_state state)
{
- if (crtc >= adev->mode_info.num_crtc) {
+ if (crtc >= adev->mode_info.num_crtc || !adev->mode_info.crtcs[crtc]) {
DRM_DEBUG("invalid crtc %d\n", crtc);
return;
}