Re: [PATCH] RDMA/rxe: check for error

[Jason Gunthorpe]

On Thu, Apr 23, 2020 at 11:48:13AM +0100, Sudip Mukherjee wrote:
> rxe_create_mmap_info() returns either NULL or an error value in ERR_PTR
> and we only checked for NULL after return. We should be using
> IS_ERR_OR_NULL to check for both.
> 
> Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@xxxxxxxxx>
>  drivers/infiniband/sw/rxe/rxe_queue.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/infiniband/sw/rxe/rxe_queue.c b/drivers/infiniband/sw/rxe/rxe_queue.c
> index ff92704de32f..ef438ce4fcfa 100644
> +++ b/drivers/infiniband/sw/rxe/rxe_queue.c
> @@ -45,7 +45,7 @@ int do_mmap_info(struct rxe_dev *rxe, struct mminfo __user *outbuf,
>  
>  	if (outbuf) {
>  		ip = rxe_create_mmap_info(rxe, buf_size, udata, buf);
> -		if (!ip)
> +		if (IS_ERR_OR_NULL(ip))
>  			goto err1;

Same comment as for the rvt patch - do not use IS_ERR_OR_NULL. If a
function uses the ERR_PTR stuff then it should not return NULL. Fix
rxe_create_mmap_info and check all call sites

Jason