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Date: Fri, 29 May 2026 13:51:16 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Jiayuan Chen <jiayuan.chen@linux.dev>
Cc: netdev@vger.kernel.org,
 syzbot+819eb928d120d2bdad0e@syzkaller.appspotmail.com, Kuniyuki Iwashima
 <kuniyu@google.com>, David Ahern <dsahern@kernel.org>, Ido Schimmel
 <idosch@nvidia.com>, "David S. Miller" <davem@davemloft.net>, Eric Dumazet
 <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>, Simon Horman
 <horms@kernel.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net v2] ipv6: anycast: insert aca into global hash under
 idev->lock
Message-ID: <20260529135116.183e083e@kernel.org>
In-Reply-To: <20260529152219.235475-1-jiayuan.chen@linux.dev>
References: <20260529152219.235475-1-jiayuan.chen@linux.dev>
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On Fri, 29 May 2026 23:22:18 +0800 Jiayuan Chen wrote:
> syzbot reported a splat [1]: a slab-use-after-free in
> ipv6_chk_acast_addr(), which walks the global inet6_acaddr_lst[] hash
> under RCU and dereferences a struct ifacaddr6 that has already been
> freed while still linked in the hash, so a later reader walks into a
> dangling node.

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