Re: [PATCH V1] accel/amdxdna: Fix potential NULL pointer access in amdxdna_gem_vmap()

[Max Zhen <max.zhen@amd.com>]

On 7/7/2026 Tue 10:23, Lizhi Hou wrote:
> If the heap BO was never vmapped before its handle was closed and the
> user then vmaps the dev BO (which triggers amdxdna_gem_vmap(heap_bo)),
> and drm_gem_vmap fails — NULL pointer dereference at abo->client->xdna.
> 
> Fix it by get xdna pointer through to_xdna_dev(to_gobj(abo)->dev).
> 
> Fixes: d76856beb4a4 ("accel/amdxdna: Refactor GEM BO handling and add helper APIs for address retrieval")
> Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
Reviewed-by: Max Zhen <max.zhen@amd.com>
> ---
>   drivers/accel/amdxdna/amdxdna_gem.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/accel/amdxdna/amdxdna_gem.c b/drivers/accel/amdxdna/amdxdna_gem.c
> index 64c7d82713b0..5033a0e5c6ab 100644
> --- a/drivers/accel/amdxdna/amdxdna_gem.c
> +++ b/drivers/accel/amdxdna/amdxdna_gem.c
> @@ -198,6 +198,7 @@ amdxdna_gem_destroy_obj(struct amdxdna_gem_obj *abo)
>    */
>   void *amdxdna_gem_vmap(struct amdxdna_gem_obj *abo)
>   {
> +	struct amdxdna_dev *xdna = to_xdna_dev(to_gobj(abo)->dev);
>   	struct iosys_map map = IOSYS_MAP_INIT_VADDR(NULL);
>   	int ret;
>   
> @@ -210,7 +211,7 @@ void *amdxdna_gem_vmap(struct amdxdna_gem_obj *abo)
>   	if (!abo->mem.kva) {
>   		ret = drm_gem_vmap(to_gobj(abo), &map);
>   		if (ret)
> -			XDNA_ERR(abo->client->xdna, "Vmap bo failed, ret %d", ret);
> +			XDNA_ERR(xdna, "Vmap bo failed, ret %d", ret);
>   		else
>   			abo->mem.kva = map.vaddr;
>   	}