From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752848AbeBGGrV (ORCPT ); Wed, 7 Feb 2018 01:47:21 -0500 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:54424 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750729AbeBGGrU (ORCPT ); Wed, 7 Feb 2018 01:47:20 -0500 Subject: Re: WARNING: kmalloc bug in tun_device_event To: syzbot , Linyu.Yuan@alcatel-sbell.com.cn, davem@davemloft.net, edumazet@google.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, peterpenkov96@gmail.com, syzkaller-bugs@googlegroups.com, willemb@google.com, xiyou.wangcong@gmail.com References: <089e082603c453a0730564931ce5@google.com> From: Jason Wang Message-ID: <7de8cd87-021a-5c8f-7df4-07be1ca651a5@redhat.com> Date: Wed, 7 Feb 2018 14:47:10 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 MIME-Version: 1.0 In-Reply-To: <089e082603c453a0730564931ce5@google.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018年02月07日 06:58, syzbot wrote: > Hello, > > syzbot hit the following crash on net-next commit > 617aebe6a97efa539cc4b8a52adccd89596e6be0 (Sun Feb 4 00:25:42 2018 +0000) > Merge tag 'usercopy-v4.16-rc1' of > git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux > > So far this crash happened 5 times on net-next, upstream. > C reproducer is attached. > syzkaller reproducer is attached. > Raw console output is attached. > compiler: gcc (GCC) 7.1.1 20170620 > .config is attached. > > IMPORTANT: if you fix the bug, please add the following tag to the > commit: > Reported-by: syzbot+e4d4f9ddd4295539735d@syzkaller.appspotmail.com > It will help syzbot understand when the bug is fixed. See footer for > details. > If you forward the report, please keep this part and the footer. > > WARNING: CPU: 1 PID: 4134 at mm/slab_common.c:1012 > kmalloc_slab+0x5d/0x70 mm/slab_common.c:1012 > Kernel panic - not syncing: panic_on_warn set ... > > CPU: 1 PID: 4134 Comm: syzkaller993072 Not tainted 4.15.0+ #221 > Hardware name: Google Google Compute Engine/Google Compute Engine, > BIOS Google 01/01/2011 > Call Trace: >  __dump_stack lib/dump_stack.c:17 [inline] >  dump_stack+0x194/0x257 lib/dump_stack.c:53 >  panic+0x1e4/0x41c kernel/panic.c:183 >  __warn+0x1dc/0x200 kernel/panic.c:547 >  report_bug+0x211/0x2d0 lib/bug.c:184 >  fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178 >  fixup_bug arch/x86/kernel/traps.c:247 [inline] >  do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296 >  do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315 >  invalid_op+0x22/0x40 arch/x86/entry/entry_64.S:1097 > RIP: 0010:kmalloc_slab+0x5d/0x70 mm/slab_common.c:1012 > RSP: 0018:ffff8801ba7ceb20 EFLAGS: 00010246 > RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff83b88bed > RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000400000008 > RBP: ffff8801ba7ceb20 R08: 1ffff100374f9cd7 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000000 R12: 0000000400000008 > R13: dffffc0000000000 R14: 00000000014080c0 R15: ffff8801b5d52080 >  __do_kmalloc mm/slab.c:3700 [inline] >  __kmalloc+0x25/0x760 mm/slab.c:3714 >  kmalloc_array include/linux/slab.h:631 [inline] >  kcalloc include/linux/slab.h:642 [inline] >  __ptr_ring_init_queue_alloc include/linux/ptr_ring.h:469 [inline] >  ptr_ring_resize_multiple include/linux/ptr_ring.h:629 [inline] >  tun_queue_resize drivers/net/tun.c:3319 [inline] >  tun_device_event+0x471/0xec0 drivers/net/tun.c:3338 >  notifier_call_chain+0x136/0x2c0 kernel/notifier.c:93 >  __raw_notifier_call_chain kernel/notifier.c:394 [inline] >  raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401 >  call_netdevice_notifiers_info+0x32/0x70 net/core/dev.c:1707 >  call_netdevice_notifiers net/core/dev.c:1725 [inline] >  dev_change_tx_queue_len+0x117/0x220 net/core/dev.c:7065 >  do_setlink+0xba7/0x3bb0 net/core/rtnetlink.c:2341 >  rtnl_newlink+0xf1c/0x1a20 net/core/rtnetlink.c:2915 >  rtnetlink_rcv_msg+0x57f/0xb10 net/core/rtnetlink.c:4587 >  netlink_rcv_skb+0x14b/0x380 net/netlink/af_netlink.c:2442 >  rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4605 >  netlink_unicast_kernel net/netlink/af_netlink.c:1308 [inline] >  netlink_unicast+0x4c4/0x6b0 net/netlink/af_netlink.c:1334 >  netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1897 >  sock_sendmsg_nosec net/socket.c:630 [inline] >  sock_sendmsg+0xca/0x110 net/socket.c:640 >  ___sys_sendmsg+0x767/0x8b0 net/socket.c:2046 >  __sys_sendmsg+0xe5/0x210 net/socket.c:2080 >  SYSC_sendmsg net/socket.c:2091 [inline] >  SyS_sendmsg+0x2d/0x50 net/socket.c:2087 >  entry_SYSCALL_64_fastpath+0x29/0xa0 > RIP: 0033:0x4463c9 > RSP: 002b:00007ffe63916e68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e > RAX: ffffffffffffffda RBX: 00000000004a7af2 RCX: 00000000004463c9 > RDX: 0000000000000000 RSI: 0000000020504000 RDI: 0000000000000004 > RBP: 00007ffe63916f08 R08: 0000000000000000 R09: 00000000004a7af2 > R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe63916f08 > R13: 0000000000403890 R14: 0000000000000000 R15: 0000000000000000 > Dumping ftrace buffer: >    (ftrace buffer empty) > Kernel Offset: disabled > Rebooting in 86400 seconds.. > > > --- > This bug is generated by a dumb bot. It may contain errors. > See https://goo.gl/tpsmEJ for details. > Direct all questions to syzkaller@googlegroups.com. > > syzbot will keep track of this bug report. > If you forgot to add the Reported-by tag, once the fix for this bug is > merged > into any tree, please reply to this email with: > #syz fix: exact-commit-title > If you want to test a patch for this bug, please reply with: > #syz test: git://repo/address.git branch > and provide the patch inline or as an attachment. > To mark this as a duplicate of another syzbot report, please reply with: > #syz dup: exact-subject-of-another-report > If it's a one-off invalid bug report, please reply with: > #syz invalid > Note: if the crash happens again, it will cause creation of a new bug > report. > Note: all commands must start from beginning of the line in the email > body. Looks like we need cap the maximum size that ptr_ring could allocate. Will post a patch soon. Thanks