RE: [PATCH] net/mlx5: fix possible stack overflows

From: Hamdan Agbariya
Date: Mon Feb 19 2024 - 04:06:19 EST


> 在 2024/2/15 16:03, Arnd Bergmann 写道:
> > On Thu, Feb 15, 2024, at 01:18, Zhu Yanjun wrote:
> >> 在 2024/2/13 18:08, Arnd Bergmann 写道:
> >>> static int
> >>> -dr_dump_rule_rx_tx(struct seq_file *file, struct mlx5dr_rule_rx_tx
> >>> *rule_rx_tx,
> >>> +dr_dump_rule_rx_tx(struct seq_file *file, char *buff,
> >>> + struct mlx5dr_rule_rx_tx *rule_rx_tx,
> >>> bool is_rx, const u64 rule_id, u8 format_ver)
> >>> {
> >>> struct mlx5dr_ste *ste_arr[DR_RULE_MAX_STES +
> >>> DR_ACTION_MAX_STES]; @@ -533,7 +532,7 @@
> dr_dump_rule_rx_tx(struct seq_file *file, struct mlx5dr_rule_rx_tx
> *rule_rx_tx,
> >>> return 0;
> >>>
> >>> while (i--) {
> >>> - ret = dr_dump_rule_mem(file, ste_arr[i], is_rx, rule_id,
> >> Before buff is reused, I am not sure whether buff should be firstly
> >> zeroed or not.
> > I don't see why it would, but if you want to zero it, that would be a
> > separate patch that is already needed on the existing code, which
> > never zeroes its buffers.
>
> Sure. I agree with you. In the existing code, the buffers are not zeroed.
>
> But to a buffer which is used for several times, it is good to zero it before it is
> used again.
>
> Can you add a new commit with the following?
>
> 1). Zero the buffers in the existing code
>

No need to zero the buffers, as it does not have any necessity and it will only affect performance.
Thanks,
Hamdan




> 2). Add the zero functionality to your patch
>
> From my perspective, it is good to the whole commit.
>
> Please Jason and Leon comment on this.
>
> Thanks,
>
> Zhu Yanjun
>
> >
> > Arnd