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Fri, 15 May 2026 08:11:43 -0700 (PDT) Date: Sat, 16 May 2026 00:11:39 +0900 From: Hyunwoo Kim To: Sultan Alsawaf Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, horms@kernel.org, kerneljasonxing@gmail.com, kuniyu@google.com, mhal@rbox.co, jiayuan.chen@linux.dev, steffen.klassert@secunet.com, ben@decadent.org.uk, herbert@gondor.apana.org.au, dsahern@kernel.org, sd@queasysnail.net, netdev@vger.kernel.org, stable@vger.kernel.org, imv4bel@gmail.com Subject: Re: [PATCH net v4] net: skbuff: propagate shared-frag marker through frag-transfer helpers Message-ID: References: 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-Disposition: inline In-Reply-To: On Fri, May 15, 2026 at 03:36:59PM +0900, Hyunwoo Kim wrote: > On Thu, May 14, 2026 at 11:26:28PM -0700, Sultan Alsawaf wrote: > > On Fri, May 15, 2026 at 02:55:35PM +0900, Hyunwoo Kim wrote: > > > Changes in v4: > > > - Include the tcp_clone_payload() propagation suggested by Sabrina. > > > - Drop the skb_try_coalesce() change; addressed by commit f84eca581739. > > > - v3: https://lore.kernel.org/all/agW4vC0r8QOUKtRT@v4bel/ > > > > > > Changes in v3: > > > - Include the skb_gro_receive() audit patch suggested by Sultan > > > - v2: https://lore.kernel.org/all/agToIEDI4TaTNLRb@v4bel/ > > > > > > Changes in v2: > > > - Also propagate SHARED_FRAG in skb_try_coalesce() and skb_shift() > > > - v1: https://lore.kernel.org/all/agRfuVOeMI5pbHhY@v4bel/ > > > > Hi Hyunwoo, > > > > Per your ask to me to use AI for exploring relevant paths [1], I've attached my > > findings from a pretty thorough day of hunting for these with Claude. > > > > None of the findings appear to be currently exploitable. > > > > Please let me know if you have any questions, and I hope you find this helpful. > > > > [1] https://lore.kernel.org/all/agWUdie1xBvBu22I@v4bel/ > > > > Thanks, > > Sultan > > Thank you so much. This is a really useful report; I'll take it and dig > further from there. > > Thanks again! > > > Best regards, > Hyunwoo Kim After analyzing the call paths, I also could not find any other user page write path triggerable on current mainline. Unless there are additional review comments, I plan to finalize the v4 patch. Thank you. Best regards, Hyunwoo Kim