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Wed, 1 Apr 2026 09:39:40 -0400 (EDT) Date: Wed, 1 Apr 2026 15:39:38 +0200 From: Greg KH To: =?utf-8?B?6ZKx5LiA6ZOt?= Cc: security@kernel.org, netdev@vger.kernel.org Subject: Re: [SECURITY] ipv6: opt_flen wrap via repeated IPV6_DSTOPTS cmsgs triggers skb_under_panic (local DoS) Message-ID: <2026040101-schilling-serpent-09cb@gregkh> 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=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Wed, Apr 01, 2026 at 08:56:22PM +0800, 钱一铭 wrote: > Hi, > > I believe I found a locally triggerable kernel bug in the IPv6 sendmsg > ancillary-data path that can panic the kernel via `skb_under_panic()` > (local DoS). As you've sent this to netdev, which is public, no need for security@k.o to get involved here. Also, as you have a reproducer, can you make a patch to fix this so you get full credit for the fix? thanks, greg k-h