| Message ID | 20171102172218.7827-1-michel@daenzer.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Am 02.11.2017 um 18:22 schrieb Michel Dänzer: > From: Michel Dänzer <michel.daenzer@amd.com> > > 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 > Signed-off-by: Michel Dänzer <michel.daenzer@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> > --- > drivers/gpu/drm/ttm/ttm_bo.c | 16 ++++------------ > 1 file 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;
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;