Re: [PATCH][next] taprio: add null check on sched_nest to avoid potential null pointer dereference

From: David Miller
Date: Tue May 07 2019 - 15:16:46 EST

From: Colin King <colin.king@xxxxxxxxxxxxx>
Date: Sun, 5 May 2019 22:50:19 +0100

> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> The call to nla_nest_start_noflag can return a null pointer and currently
> this is not being checked and this can lead to a null pointer dereference
> when the null pointer sched_nest is passed to function nla_nest_end. Fix
> this by adding in a null pointer check.
> Addresses-Coverity: ("Dereference null return value")
> Fixes: a3d43c0d56f1 ("taprio: Add support adding an admin schedule")
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>