From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A6A4C433FE for ; Fri, 10 Dec 2021 14:20:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241929AbhLJOY0 (ORCPT ); Fri, 10 Dec 2021 09:24:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53794 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241895AbhLJOYZ (ORCPT ); Fri, 10 Dec 2021 09:24:25 -0500 Received: from mail-pj1-x1031.google.com (mail-pj1-x1031.google.com [IPv6:2607:f8b0:4864:20::1031]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C868FC061746 for ; Fri, 10 Dec 2021 06:20:50 -0800 (PST) Received: by mail-pj1-x1031.google.com with SMTP id gx15-20020a17090b124f00b001a695f3734aso7693541pjb.0 for ; Fri, 10 Dec 2021 06:20:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=x2aVR+DNuZgu90KK1tYkfqnY/yJLn+drWFCVXdp6KhE=; b=Ss7eJ0fJMsSMUV3Tj1CpRcHASEXPvGiBZI8SiUMVmrIgRscPZQu5O8NBJsUUioV50e EED58cZOv6yJ/whQMVOBxtbpQ7TpAghPJFzFZw5Ln9IFSDJhnQc45mopeTfbNTz39+Rj TtzGDSKMRIMGU34181GLxdHdbrUQz8SZYVWZdmveGHy5cSo5WuL5M9Rg15wbZdtSEjaC csgBOfnNXlT1rQAe4+quyrEzDLD9enr/t8c6A0Sfvl+vnkLZPpWyCJy7VzGN4FiCjBH3 R8efgHguurGrV5oy4RCouJ+iIbW512cGxFFdfceRrkHMWMnrToQ6PSxFjIsEqb3iNvGh 23tA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=x2aVR+DNuZgu90KK1tYkfqnY/yJLn+drWFCVXdp6KhE=; b=x5hL8UuAkZ/wrORXREKIkFCgGFLs4hyz5I2gvTit2tmFG5kq/jiT2LXI/UDGHH8kxk VFI23Xg36+gQr+hQumx/PwTw3njq/RyyXMBjo3VGIiPgF+GE3lfgwL8fZ7aU79l+8eRH ekMeCj6utbFAS0z1MxzzJE+QkYJ72Md7nhHMbNLBtonM+KxdiqIJrIGrupVGokc9ZEHq HHvT5FU4jf1T2lD0cxZaYHaoC4r9hs9uICE4G2SMAkZ1qeQ/xYCXHamtk6zQwg/7ARWn vKd03nJHUm/YSvFbrzfzARLVcs9yTOtdIFYkCaN4TFYb/ZqvWz9kEz5I+PE/ZSgISc44 hGeQ== X-Gm-Message-State: AOAM531NUbVY7YqzkzIPbb4Ew032olfoKJpkY+UWEI8E+StD/71kRyzA EnfnemlR6jsBK5UpGaiHrSQ= X-Google-Smtp-Source: ABdhPJyvoXD/Xd6gvluudwg6Ou6wLqOWXFrA4zKGPJnbq9Xz2Y4AoBFkXCHLM4fE5fb1sceJoWxnAA== X-Received: by 2002:a17:90b:3b45:: with SMTP id ot5mr23916552pjb.235.1639146050359; Fri, 10 Dec 2021 06:20:50 -0800 (PST) Received: from edumazet1.svl.corp.google.com ([2620:15c:2c4:201:4f5:a6b4:3889:ebe5]) by smtp.gmail.com with ESMTPSA id g15sm4472477pfj.144.2021.12.10.06.20.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 10 Dec 2021 06:20:49 -0800 (PST) From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski Cc: netdev , Eric Dumazet , Eric Dumazet , syzbot , =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= Subject: [PATCH V2 net] sch_cake: do not call cake_destroy() from cake_init() Date: Fri, 10 Dec 2021 06:20:46 -0800 Message-Id: <20211210142046.698336-1-eric.dumazet@gmail.com> X-Mailer: git-send-email 2.34.1.173.g76aa8bc2d0-goog MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Eric Dumazet qdiscs are not supposed to call their own destroy() method from init(), because core stack already does that. syzbot was able to trigger use after free: DEBUG_LOCKS_WARN_ON(lock->magic != lock) WARNING: CPU: 0 PID: 21902 at kernel/locking/mutex.c:586 __mutex_lock_common kernel/locking/mutex.c:586 [inline] WARNING: CPU: 0 PID: 21902 at kernel/locking/mutex.c:586 __mutex_lock+0x9ec/0x12f0 kernel/locking/mutex.c:740 Modules linked in: CPU: 0 PID: 21902 Comm: syz-executor189 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:586 [inline] RIP: 0010:__mutex_lock+0x9ec/0x12f0 kernel/locking/mutex.c:740 Code: 08 84 d2 0f 85 19 08 00 00 8b 05 97 38 4b 04 85 c0 0f 85 27 f7 ff ff 48 c7 c6 20 00 ac 89 48 c7 c7 a0 fe ab 89 e8 bf 76 ba ff <0f> 0b e9 0d f7 ff ff 48 8b 44 24 40 48 8d b8 c8 08 00 00 48 89 f8 RSP: 0018:ffffc9000627f290 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88802315d700 RSI: ffffffff815f1db8 RDI: fffff52000c4fe44 RBP: ffff88818f28e000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815ebb5e R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffc9000627f458 R15: 0000000093c30000 FS: 0000555556abc400(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fda689c3303 CR3: 000000001cfbb000 CR4: 0000000000350ef0 Call Trace: tcf_chain0_head_change_cb_del+0x2e/0x3d0 net/sched/cls_api.c:810 tcf_block_put_ext net/sched/cls_api.c:1381 [inline] tcf_block_put_ext net/sched/cls_api.c:1376 [inline] tcf_block_put+0xbc/0x130 net/sched/cls_api.c:1394 cake_destroy+0x3f/0x80 net/sched/sch_cake.c:2695 qdisc_create.constprop.0+0x9da/0x10f0 net/sched/sch_api.c:1293 tc_modify_qdisc+0x4c5/0x1980 net/sched/sch_api.c:1660 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5571 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2496 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f1bb06badb9 Code: Unable to access opcode bytes at RIP 0x7f1bb06bad8f. RSP: 002b:00007fff3012a658 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f1bb06badb9 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000003 R10: 0000000000000003 R11: 0000000000000246 R12: 00007fff3012a688 R13: 00007fff3012a6a0 R14: 00007fff3012a6e0 R15: 00000000000013c2 Fixes: 046f6fd5daef ("sched: Add Common Applications Kept Enhanced (cake) qdisc") Signed-off-by: Eric Dumazet Reported-by: syzbot Acked-by: Toke Høiland-Jørgensen --- net/sched/sch_cake.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c index 3c2300d144681869a37ada0d20966f9b5b145653..857aaebd49f4315502928fb1f75d2c85eb63eb51 100644 --- a/net/sched/sch_cake.c +++ b/net/sched/sch_cake.c @@ -2736,7 +2736,7 @@ static int cake_init(struct Qdisc *sch, struct nlattr *opt, q->tins = kvcalloc(CAKE_MAX_TINS, sizeof(struct cake_tin_data), GFP_KERNEL); if (!q->tins) - goto nomem; + return -ENOMEM; for (i = 0; i < CAKE_MAX_TINS; i++) { struct cake_tin_data *b = q->tins + i; @@ -2766,10 +2766,6 @@ static int cake_init(struct Qdisc *sch, struct nlattr *opt, q->min_netlen = ~0; q->min_adjlen = ~0; return 0; - -nomem: - cake_destroy(sch); - return -ENOMEM; } static int cake_dump(struct Qdisc *sch, struct sk_buff *skb) -- 2.34.1.173.g76aa8bc2d0-goog