ACK: [SRU][J:linux-bluefield][PATCH 1/1] net/sched: flower: Add lock protection when remove filter handle

[Bartlomiej Zolnierkiewicz]

Acked-by: Bartlomiej Zolnierkiewicz <bartlomiej.zolnierkiewicz at canonical.com>

On Tue, Feb 27, 2024 at 12:03 AM William Tu <witu at nvidia.com> wrote:
>
> From: Jianbo Liu <jianbol at nvidia.com>
>
> BugLink: https://bugs.launchpad.net/bugs/2055052
>
> As IDR can't protect itself from the concurrent modification, place
> idr_remove() under the protection of tp->lock.
>
> Fixes: 08a0063df3ae ("net/sched: flower: Move filter handle initialization earlier")
> Signed-off-by: Jianbo Liu <jianbol at nvidia.com>
> Reviewed-by: Cosmin Ratiu <cratiu at nvidia.com>
> Reviewed-by: Gal Pressman <gal at nvidia.com>
> Reviewed-by: Jiri Pirko <jiri at nvidia.com>
> Acked-by: Jamal Hadi Salim <jhs at mojatatu.com>
> Link: https://lore.kernel.org/r/20240220085928.9161-1-jianbol@nvidia.com
> Signed-off-by: Jakub Kicinski <kuba at kernel.org>
> (Backported from commit 1fde0ca3a0de7e9f917668941156959dd5e9108b)
> [witu: resolve trivial conflicts in net/sched/cls_flower.c]
> Signed-off-by: William Tu <witu at nvidia.com>
> ---
>  net/sched/cls_flower.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
> index 323d8bf02fa6..a2361b632a09 100644
> --- a/net/sched/cls_flower.c
> +++ b/net/sched/cls_flower.c
> @@ -2196,9 +2196,11 @@ static int fl_change(struct net *net, struct sk_buff *in_skb,
>  errout_mask:
>         fl_mask_put(head, fnew->mask);
>  errout_idr:
> -       if (!fold)
> +       if (!fold) {
> +               spin_lock(&tp->lock);
>                 idr_remove(&head->handle_idr, fnew->handle);
> -errout:
> +               spin_unlock(&tp->lock);
> +       }
>         __fl_put(fnew);
>  errout_tb:
>         kfree(tb);