Re: [PATCH net] net: cls_flower: Remove filter from mask before freeing it

[David Miller <davem@davemloft.net>]

From: Petr Machata <petrm@mellanox.com>
Date: Mon, 4 Feb 2019 14:50:38 +0000

> In fl_change(), when adding a new rule (i.e. fold == NULL), a driver may
> reject the new rule, for example due to resource exhaustion. By that
> point, the new rule was already assigned a mask, and it was added to
> that mask's hash table. The clean-up path that's invoked as a result of
> the rejection however neglects to undo the hash table addition, and
> proceeds to free the new rule, thus leaving a dangling pointer in the
> hash table.
> 
> Fix by removing fnew from the mask's hash table before it is freed.
> 
> Fixes: 35cc3cefc4de ("net/sched: cls_flower: Reject duplicated rules
> also under skip_sw")

Please do not break up lone Fixes: tag lines in the future, I fixed it
up for you this time.

> Signed-off-by: Petr Machata <petrm@mellanox.com>
> Acked-by: Jiri Pirko <jiri@mellanox.com>
> Reviewed-by: Ido Schimmel <idosch@mellanox.com>

Applied and queued up for -stable.