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 2AEEB3DFC6B; Thu, 14 May 2026 14:37:20 +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=1778769441; cv=none; b=MUd6awukdO19Emo2wJHbhUs6d+JU1zO0aK96Wg/2Xeu8wXSd9YJ1/Kyh/cChxO4/olYkh/EEB4e+oarW1AYE7veM4+KsY2PJn8pbYXPFpWdQLb2z7/UJLqomSP0dcwvOZZblZ5blrdMLEZ0e3Wnuif/9fGOZ7TH2rB6wnPR7ERM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778769441; c=relaxed/simple; bh=hMeBZNi1IVe/BW6Daa6AdaTyoKeOM1QtRIG/C6ugctA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=maj7PDchoo4iUfntnoFIlwBRJoa3/TTBQrSMNm9H3/pmR7r8YM7l3n6uEA9/nk74ogqSPm5OWON3mcQrexcMvz59xa6eOiOezrugpHmtDoOWDUy+YsIrnu5Yos4aqa4ygWuxb6ksUGS70sHuldXWHK9+qZqiCGnH+RgNqDTFd2k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fy9q5sO8; 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="fy9q5sO8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0A73DC2BCC7; Thu, 14 May 2026 14:37:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778769440; bh=hMeBZNi1IVe/BW6Daa6AdaTyoKeOM1QtRIG/C6ugctA=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=fy9q5sO8jN+0avC9Pil/hEm2S/HpZLTKnYDd3hK76Pj2oboNYSCkNgRQIXei4sDjP BpZbaLb2LxcRpNZw0DWVjiFDPaMp9VhJM9xir6Akn2HYchHDneKCz8VtfdN3PnGcSM wM0gSGbry95vKeGxEyDGmgm8Jozv5Jk4uNTBny2LjxnRn2KFYEdHnZK3evpu9SvxBf sK8kPTdL0aql7WXwpiSJzdNSQcqlvyNFyQfnPZHpIwSvntXkCTJyn+EbvyVNTnQQ9q cgFyLrDSMwwTK9WFBRTSz4DY3Zz5wZ3Xfcp/GYRLnzBRECxYln/5gQ6NgdLOxCiEEr QWbncE60ez3VA== Message-ID: <69f72d09-8054-4d26-b277-9e9b7a8854c1@kernel.org> Date: Thu, 14 May 2026 08:37:19 -0600 Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net v2] net: skbuff: propagate shared-frag marker through frag-transfer helpers Content-Language: en-US To: Sabrina Dubroca , Hyunwoo Kim Cc: Paolo Abeni , kuba@kernel.org, steffen.klassert@secunet.com, netdev@vger.kernel.org, stable@vger.kernel.org, mhal@rbox.co, davem@davemloft.net, horms@kernel.org, edumazet@google.com, kerneljasonxing@gmail.com, herbert@gondor.apana.org.au, vakzz@zellic.io, kuniyu@google.com, jiayuan.chen@linux.dev, ben@decadent.org.uk References: <92ec6190-0255-4b7c-9524-254cb37476ab@redhat.com> From: David Ahern In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 5/14/26 4:21 AM, Sabrina Dubroca wrote: > 2026-05-14, 18:38:34 +0900, Hyunwoo Kim wrote: >> On Thu, May 14, 2026 at 10:04:29AM +0200, Paolo Abeni wrote: >>> On 5/13/26 11:07 PM, Hyunwoo Kim wrote: >> Agreed. tracing SKBFL_SHARED_FRAG propagation paths one by one is >> not a robust direction for the fix. Even minor logic changes elsewhere >> could cause the issue to resurface. >> >> As a follow-up, eliminating the in-place handling in esp_input -- accepting > > It would close this group of vulnerabilities, but there are other > parts of the networking stack that consume this flag. For those, > chasing missing flag propagation is still a useful task. > Seems like this should be an skb helper to manage the flag with really good documentation on when it needs to be set, reset and propagated. I walked skbuff.c yesterday as well, and there are several places where it is not clear if the flag needs to be propagated or not.