From 988e381d5b2939af535751fcc96972aa39c7099a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= Date: Tue, 31 Aug 2021 09:15:36 +0200 Subject: [PATCH] drm/ttm: Fix ttm_bo_move_memcpy() for subclassed struct ttm_resource MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit efcefc7127290e7e9fa98dea029163ad8eda8fb3 upstream. The code was making a copy of a struct ttm_resource. However, recently the struct ttm_resources were allowed to be subclassed and also were allowed to be malloced, hence the driver could end up assuming the copy we handed it was subclassed and worse, the original could have been freed at this point. Fix this by using the original struct ttm_resource before it is potentially freed in ttm_bo_move_sync_cleanup() v2: Base on drm-misc-next-fixes rather than drm-tip. Reported-by: Ben Skeggs Reported-by: Dave Airlie Cc: Christian König Cc: Fixes: 3bf3710e3718 ("drm/ttm: Add a generic TTM memcpy move for page-based iomem") Signed-off-by: Thomas Hellström Reviewed-by: Christian König Reviewed-by: Ben Skeggs Link: https://patchwork.freedesktop.org/patch/msgid/20210831071536.80636-1-thomas.hellstrom@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/ttm/ttm_bo_util.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c index 763fa6f4e07de..1c5ffe2935af5 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_util.c +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c @@ -143,7 +143,6 @@ int ttm_bo_move_memcpy(struct ttm_buffer_object *bo, struct ttm_resource *src_mem = bo->resource; struct ttm_resource_manager *src_man = ttm_manager_type(bdev, src_mem->mem_type); - struct ttm_resource src_copy = *src_mem; union { struct ttm_kmap_iter_tt tt; struct ttm_kmap_iter_linear_io io; @@ -173,11 +172,11 @@ int ttm_bo_move_memcpy(struct ttm_buffer_object *bo, } ttm_move_memcpy(bo, dst_mem->num_pages, dst_iter, src_iter); - src_copy = *src_mem; - ttm_bo_move_sync_cleanup(bo, dst_mem); if (!src_iter->ops->maps_tt) - ttm_kmap_iter_linear_io_fini(&_src_iter.io, bdev, &src_copy); + ttm_kmap_iter_linear_io_fini(&_src_iter.io, bdev, src_mem); + ttm_bo_move_sync_cleanup(bo, dst_mem); + out_src_iter: if (!dst_iter->ops->maps_tt) ttm_kmap_iter_linear_io_fini(&_dst_iter.io, bdev, dst_mem);