From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 117E526B0A9; Tue, 17 Feb 2026 22:08:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771366113; cv=none; b=S6IqI6RxF09Pf2fZL/jbG7CM7PYk1XLV/WGMXSlfHe5lmqJSNaL9KM283hE2Qa8ChM2XDWVKyTtIc3hwK/pvm2+IAq4QUeE7nR9FGGoc66CZ8aBIaGYH8aO+i1KCHxk5uRipOgVbZ7TaxrDuFXUPSsOL9H3960gZuTsjnp3zG8o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771366113; c=relaxed/simple; bh=zIwCo0jmxFRZsEDqRMaqYmvvZJGYdVREl1QvazmykW4=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ahyAD/TNWJZHBXfZlOD+F++aHElkibnYxwncD0GousW6Bq3djroqM/SHxdcapAeTIRZLzYPyyttdTmIG2J6pSRoT054EmoeNCafbhaKdu7icBvtM6fMacDKRTtMMqRfhvwKbp2R92BMjv05VUTSarkXkLGGvDVRGPxXsURZU/wM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=KauAiK2R; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="KauAiK2R" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5EBCBC4CEF7; Tue, 17 Feb 2026 22:08:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1771366112; bh=zIwCo0jmxFRZsEDqRMaqYmvvZJGYdVREl1QvazmykW4=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=KauAiK2ReggbudOBeR9PyyjDjf35pOp4E692h0tcwRcqMEXj12XKcnBpovTMmRpct y/+Aoo9TzJIipsbvswhttNfTNV1vXkOWowlk9cPEQf58Qjc3fcJ4VCbfNIcWyU9Jik grkXqP8Q5emSKuG9AbJFRbhV1EA5o51xTY7pvIvWexDk+1k2mNFb70sOhfTKCINzQf XChkdpl7jGKx3d7HlEdW8FsuemxHfeMPON7Oclu7CiSzwRrP/F1+C/cWDtharDVmsm TM6Tz+fGiobnpmRbwcmoh2XEl/QZ2liOtUYO2lSK+7j8VtRgX45CzjWqDClCWVt7YE 6LHdvi3/gZNig== Date: Tue, 17 Feb 2026 14:08:31 -0800 From: Jakub Kicinski To: Martin KaFai Lau Cc: Feng Yang , andrii@kernel.org, ast@kernel.org, bpf@vger.kernel.org, daniel@iogearbox.net, davem@davemloft.net, edumazet@google.com, horms@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com Subject: Re: [PATCH v5] bpf: test_run: Fix the null pointer dereference issue in bpf_lwt_xmit_push_encap Message-ID: <20260217140831.52fac4ca@kernel.org> In-Reply-To: <6528c028-1224-4737-b902-e631641ddb37@linux.dev> References: <249d6576-2259-4785-87b6-619052b4ce75@linux.dev> <20260211075240.70095-1-yangfeng59949@163.com> <6528c028-1224-4737-b902-e631641ddb37@linux.dev> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Tue, 17 Feb 2026 10:08:29 -0800 Martin KaFai Lau wrote: > > The reason for the CI test failure. > > Make sense, but the early point stays the same: the user-provided skb > can have unexpected data. Either an skb->protocol is not handled here, > or the earlier dst lookup has an error. I don't know what the current > active users left in lwt are. Unless there is an issue with missing > skb_dst() in other mainstream program types (e.g., tc), I would prefer > to add a check in bpf_lwt_push_ip_encap() instead of complicating > bpf_prog_test_run_skb() further. Can bpf_prog_test_run_skb() simply not support LWT then? Having fastpath checks for test harness really feels like duct tape