Re: [PATCH] thunderbolt: Fix to check the return value of kmemdup

[Mika Westerberg]

On Tue, Mar 19, 2019 at 01:38:34PM -0500, Aditya Pakki wrote:
> uuid in add_switch is allocted via kmemdup which can fail. The patch
> logs the error in such a scenario.
> 
> Signed-off-by: Aditya Pakki <pakki001@xxxxxxx>
> ---
>  drivers/thunderbolt/icm.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c
> index e3fc920af682..8df8057cd79e 100644
> --- a/drivers/thunderbolt/icm.c
> +++ b/drivers/thunderbolt/icm.c
> @@ -473,6 +473,7 @@ static void add_switch(struct tb_switch *parent_sw, u64 route,
>  		goto out;
>  
>  	sw->uuid = kmemdup(uuid, sizeof(*uuid), GFP_KERNEL);
> +	WARN_ONCE(!sw->uuid, "%s: sw->uuid = NULL", __func__);

I don't think it is good idea to continue here since uuid is kind of
needed. Maybe do the same as above (goto out) with a useful error
message along the lines of "cannot allocate memory for switch" or so.

Remember to use tb_switch_put() in that case.