From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f69.google.com (mail-oo1-f69.google.com [209.85.161.69]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 545612E0B71 for ; Thu, 23 Apr 2026 14:59:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.69 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776956389; cv=none; b=B8JI2SQYfJCXyUgJOv/Ww022JZpZfz3owO/lxPDgDptbggA5hp2HD1V6EoMSmydEeIpc6Ryw0gMxShkrg3W3qq8+WxPug9I2ziSpeiN3ne98pv2Q2u76RNuER9cRNuIMYBnSIOKcl6DS/2L/IXhfv5kC6zi6BNzxGc4SaAE3i8Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776956389; c=relaxed/simple; bh=If6Mb/S1ZsOVfgxtDmu/wCQJemWSEhglJAFELaq7rbc=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To:Cc: Content-Type; b=Q/I/y+p84lRjQ2t4re8TG0mFKsYZmBQ5HruK2j9nGm6BLZr9bB5drSoa6g6Lv9KsO7TQ66KDZVAZ6B//PsGVPiTo/U7rOPzLx45rCbnLlFcAgG2GpeeTXrFWPEQmO+XqHP3JsVPiUQCZMznXIYiTZ8RbOgCe5h6Izwh5J6+RcPk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.161.69 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oo1-f69.google.com with SMTP id 006d021491bc7-68cfc614246so8397737eaf.3 for ; Thu, 23 Apr 2026 07:59:48 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776956387; x=1777561187; h=cc:to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=U1NlAwgaAPzBKKSxBGbiIQ9c9bd/h88zyiSOgY7aTWA=; b=CbgrCRtQi/nSw2J+jQQk8Z8NzdMh6EvunTcftlBV05h/tjRXGZRuWo8prGjjsnV5xa mnjbvfDIQi5c04AGSuGjo9JdH8GvUIt1EWi28iCm9crDp3OCu+4FeA9yKeNtT0X7xNG0 KO0K0Hwa5YJ1QMpoZebXmSvAPhMS2ODA2nsjPs2XJngcMAw+pb+YsRQ4w+j5i7dI6hqW OJx6uYSaFD2s5Gx2COsy9vig7uLZf0UYtf2vkZatHsYDzxORAYkQMOdQCbwg6e1swAMv HJILep3eQjrTrwNVsuk/4y3apSa0CEHE0cpc2v9D0JysO1pGj9n8knlZR3GUueLGQyM+ eYaA== X-Forwarded-Encrypted: i=1; AFNElJ8j6Ytcay/quF+3ngTxrWFHAUv1AIZVbilVyJJYVUD8j8//teeWJhb8E7oHvt+Nipkhx9y0xLOK8DfKs8M=@vger.kernel.org X-Gm-Message-State: AOJu0YxBnlkHT0LLB4CbUi/QOaXjWMNWH9QPsP+bANeFrVs8Zc8f6fAp +FN/yeni9+U1ftCw3fK0XhKr5bCl5fT7DzZOZKUN4XzH6raq0ePwtz3LM8hnhtJqAp0TejRgHwO Y+dZqMYIl5Ahqwx2G8ZxUk+SwtRjvlPw8Gj/nWD7Z9iqsGbgBDXuXuPcbuFA= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:4b02:b0:694:92fe:54f2 with SMTP id 006d021491bc7-69492fe5782mr8923231eaf.56.1776956387278; Thu, 23 Apr 2026 07:59:47 -0700 (PDT) Date: Thu, 23 Apr 2026 07:59:47 -0700 In-Reply-To: X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69ea33e3.a00a0220.9259.002a.GAE@google.com> Subject: Re: [PATCH v2] ipv6: fix memory leak in __ip6_make_skb() when queue is empty From: syzbot To: willemdebruijn.kernel@gmail.com Cc: 25181214217@stu.xidian.edu.cn, davem@davemloft.net, dsahern@kernel.org, edumazet@google.com, horms@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, sd@queasysnail.net, willemdebruijn.kernel@gmail.com Content-Type: text/plain; charset="UTF-8" > Mingyu Wang wrote: >> During fuzzing with failslab enabled, a memory leak was observed in the >> IPv6 UDP send path. >> >> The root cause resides in __ip6_make_skb(). In extremely rare cases >> (such as fault injection or specific empty payload conditions), > > Can you elaborate on this? Which fault injection lets > __ip6_append_data succeed without writing data? > >> __ip6_append_data() may succeed but leave the socket's write queue >> empty. >> >> When __ip6_make_skb() is subsequently called, __skb_dequeue(queue) >> returns NULL. The previous logic handled this by executing a 'goto out;', >> which completely bypassed the call to ip6_cork_release(cork). >> >> Since the 'cork' structure actively holds a reference to the routing >> entry (dst_entry) and potentially other allocated options, skipping >> the release cleanly leaks these resources. >> >> Fix this by introducing an 'out_cork_release' label and jumping to it >> when skb is NULL, ensuring the cork state is always properly cleaned up. >> The now-unused 'out' label is also removed to prevent compiler warnings. >> >> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") > > I think this is > > Fixes: 6422398c2ab0 ("ipv6: introduce ipv6_make_skb") > >> Reported-by: syzbot+e5d6936b9f4545fd88ab@syzkaller.appspotmail.com >> Signed-off-by: Mingyu Wang <25181214217@stu.xidian.edu.cn> I see the command but can't find the corresponding bug. The email is sent to syzbot+HASH@syzkaller.appspotmail.com address but the HASH does not correspond to any known bug. Please double check the address.