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| author | Michel Dänzer <michel.daenzer@amd.com> | 2017-11-03 16:00:35 +0100 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2017-11-04 09:48:01 -0400 |
| commit | e1fc12c5d9ad06a2a74e97a91f1b0c5f4c723b50 (patch) | |
| tree | a138da480d215bdc6608d6c275bdc6874d4bbb92 /drivers/gpu/drm/ttm | |
| parent | 37c5f2c99adf63adf13f1ca309a1ffce25c5589a (diff) | |
| download | linux-e1fc12c5d9ad06a2a74e97a91f1b0c5f4c723b50.tar.bz2 | |
drm/ttm: Always and only destroy bo->ttm_resv in ttm_bo_release_list
Fixes a use-after-free due to a race condition in
ttm_bo_cleanup_refs_and_unlock, which allows one task to reserve a BO
and destroy its ttm_resv while another task is waiting for it to signal
in reservation_object_wait_timeout_rcu.
v2:
* Always initialize bo->ttm_resv in ttm_bo_init_reserved
(Christian König)
Fixes: 0d2bd2ae045d "drm/ttm: fix memory leak while individualizing BOs"
Reviewed-by: Chunming Zhou <david1.zhou@amd.com> # v1
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Diffstat (limited to 'drivers/gpu/drm/ttm')
| -rw-r--r-- | drivers/gpu/drm/ttm/ttm_bo.c | 16 |
1 files changed, 4 insertions, 12 deletions
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index 379ec41d2c69..c088703777e2 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -150,8 +150,7 @@ static void ttm_bo_release_list(struct kref *list_kref) ttm_tt_destroy(bo->ttm); atomic_dec(&bo->glob->bo_count); dma_fence_put(bo->moving); - if (bo->resv == &bo->ttm_resv) - reservation_object_fini(&bo->ttm_resv); + reservation_object_fini(&bo->ttm_resv); mutex_destroy(&bo->wu_mutex); if (bo->destroy) bo->destroy(bo); @@ -402,14 +401,11 @@ static int ttm_bo_individualize_resv(struct ttm_buffer_object *bo) if (bo->resv == &bo->ttm_resv) return 0; - reservation_object_init(&bo->ttm_resv); BUG_ON(!reservation_object_trylock(&bo->ttm_resv)); r = reservation_object_copy_fences(&bo->ttm_resv, bo->resv); - if (r) { + if (r) reservation_object_unlock(&bo->ttm_resv); - reservation_object_fini(&bo->ttm_resv); - } return r; } @@ -457,10 +453,8 @@ static void ttm_bo_cleanup_refs_or_queue(struct ttm_buffer_object *bo) if (reservation_object_test_signaled_rcu(&bo->ttm_resv, true)) { ttm_bo_del_from_lru(bo); spin_unlock(&glob->lru_lock); - if (bo->resv != &bo->ttm_resv) { + if (bo->resv != &bo->ttm_resv) reservation_object_unlock(&bo->ttm_resv); - reservation_object_fini(&bo->ttm_resv); - } ttm_bo_cleanup_memtype_use(bo); return; @@ -560,8 +554,6 @@ static int ttm_bo_cleanup_refs_and_unlock(struct ttm_buffer_object *bo, } ttm_bo_del_from_lru(bo); - if (!list_empty(&bo->ddestroy) && (bo->resv != &bo->ttm_resv)) - reservation_object_fini(&bo->ttm_resv); list_del_init(&bo->ddestroy); kref_put(&bo->list_kref, ttm_bo_ref_bug); @@ -1210,8 +1202,8 @@ int ttm_bo_init_reserved(struct ttm_bo_device *bdev, lockdep_assert_held(&bo->resv->lock.base); } else { bo->resv = &bo->ttm_resv; - reservation_object_init(&bo->ttm_resv); } + reservation_object_init(&bo->ttm_resv); atomic_inc(&bo->glob->bo_count); drm_vma_node_reset(&bo->vma_node); bo->priority = 0; |