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[195.231.45.245]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-c25d044d776sm96589266b.62.2026.09.02.02.24.09 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 02 Sep 2026 02:24:10 -0700 (PDT) Message-ID: <0d3f33cf-d1db-451b-a4a6-25b22fd9bb5b@redhat.com> Date: Wed, 2 Sep 2026 11:24:08 +0200 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next 1/2] net: Make skb_ext_put_sp() idempotent To: Jakub Sitnicki Cc: netdev@vger.kernel.org, Florian Westphal , "David S. Miller" , Eric Dumazet , Simon Horman , Jeremy Kerr , Matt Johnston , Steffen Klassert , Herbert Xu , kernel-team@cloudflare.com, Jakub Kicinski References: <20260831-skb-ext-prep-work-v1-0-ecc2a8542fd9@cloudflare.com> <20260831-skb-ext-prep-work-v1-1-ecc2a8542fd9@cloudflare.com> <20260901171520.072acdd2@kernel.org> <87ld9k2oaq.fsf@cloudflare.com> From: Paolo Abeni Content-Language: en-US In-Reply-To: <87ld9k2oaq.fsf@cloudflare.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/2/26 7:51 AM, Jakub Sitnicki wrote: > On Tue, Sep 01, 2026 at 05:15 PM -07, Jakub Kicinski wrote: >> On Mon, 31 Aug 2026 08:27:38 +0200 Jakub Sitnicki wrote: >>> + if (!sp->len) >>> + return; >> >> Somewhat mixed feelings about explicitly checking what is the loop >> bound, anyway. But I guess you can argue we shouldn't write len? >> Probably not worth a respin either way > > You read my mind. Then I thought maybe I'm trying to be smarter than the > compiler? But it seems that neither clang nor gcc eliminate the write: > > https://godbolt.org/z/EcWTdEYqh I'm a little late here, but it looks like sashiko cataloged as pre-existing a couple of issues that on top of this series can new lead to memory corruption: https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260831-skb-ext-prep-work-v1-0-ecc2a8542fd9%40cloudflare.com Could you please have a look? /P