From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from r3-23.sinamail.sina.com.cn (r3-23.sinamail.sina.com.cn [202.108.3.23]) (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 95F74625 for ; Mon, 25 Aug 2025 12:44:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.108.3.23 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756125905; cv=none; b=MbjcAd9LZ++5Q279Vk+25+ZNKB7LFNkgFcJFfVZQFYWmwiRJSWvKOHv8tbMhUQpz6HUpy32FKUS5kyBvtfiOzFiQezAnjAA+QjjSXGL2z+Y/LqSyCpbirna4xR9CQUtRDY7wIrUSG1W01q3bWgmRQGidHcMdSyMCiDvi+rDUZyQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756125905; c=relaxed/simple; bh=/JbjbrhVDVkUyw1YvInRbr6tGZdpT+oUI3QZ7pWUu/U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=UNczv5++y8zwDmOP8AraIr4llikikmz7aeVYcjW+eDpeAOzzFk4eSJNiRpea10i6hCjQng97YjmF1QHMMbUT6Tw1PA2OIU7RG+qJF1LR5lVuG0MuO/SyGZnhtsYKPLHsxaPBAGoYwKdTGaP1kPxjTI6if6oxIwohmCXCyBRz020= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com; spf=pass smtp.mailfrom=sina.com; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b=JyX6TjbP; arc=none smtp.client-ip=202.108.3.23 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b="JyX6TjbP" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sina.com; s=201208; t=1756125900; bh=3sZPd77q5KVVinFJmwZ+jxwQSxIoFVivZawfo2e4vng=; h=From:Subject:Date:Message-ID; b=JyX6TjbPDcifpYGfs641FFhyDiTwOkIecvchYger7iinraEDGvVnV8ajzJbO2Ieut Oa6f45OgwGGRT/5QyJ8IgqKXKBrnhfjzr/5xZ/zBmq0CBk6/xgn6M78BtMnGEKwzah lwKONBHiTz0CqjH5PZmTPtVzD8MZboczVjCBgiBQ= X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([114.249.58.236]) by sina.com (10.54.253.31) with ESMTP id 68AC5AC0000075E5; Mon, 25 Aug 2025 20:44:50 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com Authentication-Results: sina.com; spf=none smtp.mailfrom=hdanton@sina.com; dkim=none header.i=none; dmarc=none action=none header.from=hdanton@sina.com X-SMAIL-MID: 7647576816250 X-SMAIL-UIID: 7327EC2BC30A4B91906D41C871624B80-20250825-204450-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [net?] KASAN: slab-use-after-free Write in __xfrm_state_delete Date: Mon, 25 Aug 2025 20:44:37 +0800 Message-ID: <20250825124438.5472-1-hdanton@sina.com> In-Reply-To: <68ab6633.050a0220.37038e.0079.GAE@google.com> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit > Date: Sun, 24 Aug 2025 12:21:23 -0700 [thread overview] > syzbot has found a reproducer for the following issue on: > > HEAD commit: b1c92cdf5af3 Merge branch 'net-wangxun-complete-ethtool-co.. > git tree: net-next > console output: https://syzkaller.appspot.com/x/log.txt?x=1411b062580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=67b99ceb67d33475 > dashboard link: https://syzkaller.appspot.com/bug?extid=a25ee9d20d31e483ba7b > compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14221862580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=159fba34580000 #syz test --- x/net/xfrm/xfrm_state.c +++ y/net/xfrm/xfrm_state.c @@ -615,6 +615,8 @@ static void xfrm_state_gc_destroy(struct put_page(x->xfrag.page); xfrm_dev_state_free(x); security_xfrm_state_free(x); + x->km.state++; + xfrm_state_delete(x); xfrm_state_free(x); } @@ -816,7 +818,11 @@ int __xfrm_state_delete(struct xfrm_stat x->km.state = XFRM_STATE_DEAD; spin_lock(&net->xfrm.xfrm_state_lock); - list_del(&x->km.all); + if (list_empty(&x->km.all)) { + spin_unlock(&net->xfrm.xfrm_state_lock); + return 0; + } + list_del_init(&x->km.all); hlist_del_rcu(&x->bydst); hlist_del_rcu(&x->bysrc); if (x->km.seq) --