Re: [PATCH net] net/sched: cls_flow: avoid integer overflow in perturb_period

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From: Jakub Kicinski

Date: Tue Oct 20 2026 - 17:24:48 EST

On Fri, 16 Oct 2026 12:03:30 +0800 Wei Tao wrote:
> flow_change() calculates perturb_period by directly multiplying
> nla_get_u32(tb[TCA_FLOW_PERTURB]) by HZ, without any overflow
> protection. Since perturb_period is a u32, the multiplication
> overflows when the value from netlink exceeds UINT_MAX / HZ.
> The result can be an unexpectedly short period or even zero.

Same questions / treatment as your cls_fw patch.
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