Re: [PATCH] RDMA/core: Add error handling in rdma_user_mmap_disassociate.

[Leon Romanovsky <leon@kernel.org>]

On Wed, Jan 14, 2026 at 08:53:24PM +0000, Danila Chernetsov wrote:
> rdma_user_mmap_disassociate can be called before
> ib_set_client_data(device, &uverbs_client, uverbs_dev);

It is not.

Thanks

> and cause an error when calling ib_get_client_data.
> Also, consider checking the result of ib_get_client_data to handle errors
>  in other functions.
> 
> Fixes: 51976c6cd786 ("RDMA/core: Provide rdma_user_mmap_disassociate() to disassociate mmap pages")
> Signed-off-by: Danila Chernetsov <listdansp@mail.ru>
> ---
>  drivers/infiniband/core/uverbs_main.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c
> index 973fe2c7ef53..a8a2d87f4d3e 100644
> --- a/drivers/infiniband/core/uverbs_main.c
> +++ b/drivers/infiniband/core/uverbs_main.c
> @@ -901,10 +901,12 @@ void uverbs_user_mmap_disassociate(struct ib_uverbs_file *ufile)
>   * This function should be called by drivers that need to disable mmaps for the
>   * device, for instance because it is going to be reset.
>   */
> -void rdma_user_mmap_disassociate(struct ib_device *device)
> +int rdma_user_mmap_disassociate(struct ib_device *device)
>  {
>  	struct ib_uverbs_device *uverbs_dev =
>  		ib_get_client_data(device, &uverbs_client);
> +	if (!uverbs_dev)
> +		return -ENODEV;
>  	struct ib_uverbs_file *ufile;
>  
>  	mutex_lock(&uverbs_dev->lists_mutex);
> @@ -913,6 +915,7 @@ void rdma_user_mmap_disassociate(struct ib_device *device)
>  			uverbs_user_mmap_disassociate(ufile);
>  	}
>  	mutex_unlock(&uverbs_dev->lists_mutex);
> +	return 0;
>  }
>  EXPORT_SYMBOL(rdma_user_mmap_disassociate);
>  
> -- 
> 2.25.1
> 
>