[PATCH 2/4] drm/panthor: Keep a ref to the VM at the panthor_kernel_bo level
Boris Brezillon
boris.brezillon at collabora.com
Thu May 2 18:38:10 UTC 2024
Avoids use-after-free situations when panthor_fw_unplug() is called
and the kernel BO was mapped to the FW VM.
Signed-off-by: Boris Brezillon <boris.brezillon at collabora.com>
---
drivers/gpu/drm/panthor/panthor_fw.c | 4 ++--
drivers/gpu/drm/panthor/panthor_gem.c | 8 +++++---
drivers/gpu/drm/panthor/panthor_gem.h | 8 ++++++--
drivers/gpu/drm/panthor/panthor_heap.c | 8 ++++----
drivers/gpu/drm/panthor/panthor_sched.c | 11 +++++------
5 files changed, 22 insertions(+), 17 deletions(-)
diff --git a/drivers/gpu/drm/panthor/panthor_fw.c b/drivers/gpu/drm/panthor/panthor_fw.c
index 181395e2859a..b41685304a83 100644
--- a/drivers/gpu/drm/panthor/panthor_fw.c
+++ b/drivers/gpu/drm/panthor/panthor_fw.c
@@ -453,7 +453,7 @@ panthor_fw_alloc_queue_iface_mem(struct panthor_device *ptdev,
ret = panthor_kernel_bo_vmap(mem);
if (ret) {
- panthor_kernel_bo_destroy(panthor_fw_vm(ptdev), mem);
+ panthor_kernel_bo_destroy(mem);
return ERR_PTR(ret);
}
@@ -1133,7 +1133,7 @@ void panthor_fw_unplug(struct panthor_device *ptdev)
panthor_fw_stop(ptdev);
list_for_each_entry(section, &ptdev->fw->sections, node)
- panthor_kernel_bo_destroy(panthor_fw_vm(ptdev), section->mem);
+ panthor_kernel_bo_destroy(section->mem);
/* We intentionally don't call panthor_vm_idle() and let
* panthor_mmu_unplug() release the AS we acquired with
diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c
index d6483266d0c2..38f560864879 100644
--- a/drivers/gpu/drm/panthor/panthor_gem.c
+++ b/drivers/gpu/drm/panthor/panthor_gem.c
@@ -26,18 +26,18 @@ static void panthor_gem_free_object(struct drm_gem_object *obj)
/**
* panthor_kernel_bo_destroy() - Destroy a kernel buffer object
- * @vm: The VM this BO was mapped to.
* @bo: Kernel buffer object to destroy. If NULL or an ERR_PTR(), the destruction
* is skipped.
*/
-void panthor_kernel_bo_destroy(struct panthor_vm *vm,
- struct panthor_kernel_bo *bo)
+void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo)
{
+ struct panthor_vm *vm;
int ret;
if (IS_ERR_OR_NULL(bo))
return;
+ vm = bo->vm;
panthor_kernel_bo_vunmap(bo);
if (drm_WARN_ON(bo->obj->dev,
@@ -53,6 +53,7 @@ void panthor_kernel_bo_destroy(struct panthor_vm *vm,
drm_gem_object_put(bo->obj);
out_free_bo:
+ panthor_vm_put(vm);
kfree(bo);
}
@@ -106,6 +107,7 @@ panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm,
if (ret)
goto err_free_va;
+ kbo->vm = panthor_vm_get(vm);
bo->exclusive_vm_root_gem = panthor_vm_root_gem(vm);
drm_gem_object_get(bo->exclusive_vm_root_gem);
bo->base.base.resv = bo->exclusive_vm_root_gem->resv;
diff --git a/drivers/gpu/drm/panthor/panthor_gem.h b/drivers/gpu/drm/panthor/panthor_gem.h
index 3bccba394d00..e43021cf6d45 100644
--- a/drivers/gpu/drm/panthor/panthor_gem.h
+++ b/drivers/gpu/drm/panthor/panthor_gem.h
@@ -61,6 +61,11 @@ struct panthor_kernel_bo {
*/
struct drm_gem_object *obj;
+ /**
+ * @vm: VM this private buffer is attached to.
+ */
+ struct panthor_vm *vm;
+
/**
* @va_node: VA space allocated to this GEM.
*/
@@ -136,7 +141,6 @@ panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm,
size_t size, u32 bo_flags, u32 vm_map_flags,
u64 gpu_va);
-void panthor_kernel_bo_destroy(struct panthor_vm *vm,
- struct panthor_kernel_bo *bo);
+void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo);
#endif /* __PANTHOR_GEM_H__ */
diff --git a/drivers/gpu/drm/panthor/panthor_heap.c b/drivers/gpu/drm/panthor/panthor_heap.c
index 143fa35f2e74..65921296a18c 100644
--- a/drivers/gpu/drm/panthor/panthor_heap.c
+++ b/drivers/gpu/drm/panthor/panthor_heap.c
@@ -127,7 +127,7 @@ static void panthor_free_heap_chunk(struct panthor_vm *vm,
heap->chunk_count--;
mutex_unlock(&heap->lock);
- panthor_kernel_bo_destroy(vm, chunk->bo);
+ panthor_kernel_bo_destroy(chunk->bo);
kfree(chunk);
}
@@ -183,7 +183,7 @@ static int panthor_alloc_heap_chunk(struct panthor_device *ptdev,
return 0;
err_destroy_bo:
- panthor_kernel_bo_destroy(vm, chunk->bo);
+ panthor_kernel_bo_destroy(chunk->bo);
err_free_chunk:
kfree(chunk);
@@ -391,7 +391,7 @@ int panthor_heap_return_chunk(struct panthor_heap_pool *pool,
mutex_unlock(&heap->lock);
if (removed) {
- panthor_kernel_bo_destroy(pool->vm, chunk->bo);
+ panthor_kernel_bo_destroy(chunk->bo);
kfree(chunk);
ret = 0;
} else {
@@ -587,7 +587,7 @@ void panthor_heap_pool_destroy(struct panthor_heap_pool *pool)
drm_WARN_ON(&pool->ptdev->base, panthor_heap_destroy_locked(pool, i));
if (!IS_ERR_OR_NULL(pool->gpu_contexts))
- panthor_kernel_bo_destroy(pool->vm, pool->gpu_contexts);
+ panthor_kernel_bo_destroy(pool->gpu_contexts);
/* Reflects the fact the pool has been destroyed. */
pool->vm = NULL;
diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
index 1d2708c3ab0a..6ea094b00cf9 100644
--- a/drivers/gpu/drm/panthor/panthor_sched.c
+++ b/drivers/gpu/drm/panthor/panthor_sched.c
@@ -826,8 +826,8 @@ static void group_free_queue(struct panthor_group *group, struct panthor_queue *
panthor_queue_put_syncwait_obj(queue);
- panthor_kernel_bo_destroy(group->vm, queue->ringbuf);
- panthor_kernel_bo_destroy(panthor_fw_vm(group->ptdev), queue->iface.mem);
+ panthor_kernel_bo_destroy(queue->ringbuf);
+ panthor_kernel_bo_destroy(queue->iface.mem);
kfree(queue);
}
@@ -837,15 +837,14 @@ static void group_release_work(struct work_struct *work)
struct panthor_group *group = container_of(work,
struct panthor_group,
release_work);
- struct panthor_device *ptdev = group->ptdev;
u32 i;
for (i = 0; i < group->queue_count; i++)
group_free_queue(group, group->queues[i]);
- panthor_kernel_bo_destroy(panthor_fw_vm(ptdev), group->suspend_buf);
- panthor_kernel_bo_destroy(panthor_fw_vm(ptdev), group->protm_suspend_buf);
- panthor_kernel_bo_destroy(group->vm, group->syncobjs);
+ panthor_kernel_bo_destroy(group->suspend_buf);
+ panthor_kernel_bo_destroy(group->protm_suspend_buf);
+ panthor_kernel_bo_destroy(group->syncobjs);
panthor_vm_put(group->vm);
kfree(group);
--
2.44.0
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