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From: Eric Dumazet <edumazet@google.com>
Date: Mon, 25 Mar 2024 14:08:36 +0100
Message-ID: <CANn89iKbygQsCLcb0STk7DVnseNQ6rkSxeJ1cFGDaufDo5eSgg@mail.gmail.com>
Subject: Re: [syzbot] [net?] KASAN: slab-use-after-free Read in __ethtool_get_link_ksettings
To: Denis Kirjanov <dkirjanov@suse.de>
Cc: syzbot <syzbot+5fe14f2ff4ccbace9a26@syzkaller.appspotmail.com>, 
	davem@davemloft.net, kuba@kernel.org, linux-kernel@vger.kernel.org, 
	netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com
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On Mon, Mar 25, 2024 at 1:10=E2=80=AFPM Denis Kirjanov <dkirjanov@suse.de> =
wrote:
>
>
>
> On 3/22/24 23:10, syzbot wrote:
> > Hello,
> >
> > syzbot found the following issue on:
> >
> > HEAD commit:    61387b8dcf1d Merge tag 'for-6.9/dm-vdo' of git://git.ke=
rne..
> > git tree:       upstream
> > console output: https://syzkaller.appspot.com/x/log.txt?x=3D11effbd1180=
000
> > kernel config:  https://syzkaller.appspot.com/x/.config?x=3Dc6aea81bc9f=
f5e99
> > dashboard link: https://syzkaller.appspot.com/bug?extid=3D5fe14f2ff4ccb=
ace9a26
> > compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for=
 Debian) 2.40
> >
> > Unfortunately, I don't have any reproducer for this issue yet.
> >
> > Downloadable assets:
> > disk image: https://storage.googleapis.com/syzbot-assets/b972a52930fa/d=
isk-61387b8d.raw.xz
> > vmlinux: https://storage.googleapis.com/syzbot-assets/caa2592898b6/vmli=
nux-61387b8d.xz
> > kernel image: https://storage.googleapis.com/syzbot-assets/4187257afcc5=
/bzImage-61387b8d.xz
> >
> > IMPORTANT: if you fix the issue, please add the following tag to the co=
mmit:
> > Reported-by: syzbot+5fe14f2ff4ccbace9a26@syzkaller.appspotmail.com
> >
> > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> > BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x186/0=
x190 net/ethtool/ioctl.c:441
> > Read of size 8 at addr ffff888021f46308 by task kworker/0:4/5169
> >
> > CPU: 0 PID: 5169 Comm: kworker/0:4 Not tainted 6.8.0-syzkaller-05562-g6=
1387b8dcf1d #0
> > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS=
 Google 02/29/2024
> > Workqueue: infiniband ib_cache_event_task
> > Call Trace:
> >  <TASK>
> >  __dump_stack lib/dump_stack.c:88 [inline]
> >  dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
> >  print_address_description mm/kasan/report.c:377 [inline]
> >  print_report+0xc3/0x620 mm/kasan/report.c:488
> >  kasan_report+0xd9/0x110 mm/kasan/report.c:601
> >  __ethtool_get_link_ksettings+0x186/0x190 net/ethtool/ioctl.c:441
> >  __ethtool_get_link_ksettings+0xf5/0x190 net/ethtool/ioctl.c:445
>
> Hmm, report says that we have a net_device freed even that we have a dev_=
hold()
> before __ethtool_get_link_ksettings()

 dev_hold(dev) might be done too late, the device is already being dismantl=
ed.

ib_device_get_netdev() should probably be done under RTNL locking,
otherwise the final part is racy :

if (res && res->reg_state !=3D NETREG_REGISTERED) {
     dev_put(res);
     return NULL;
}


>
> >  ib_get_eth_speed+0x123/0xb50 drivers/infiniband/core/verbs.c:1984
> >  siw_query_port+0x3c/0x3e0 drivers/infiniband/sw/siw/siw_verbs.c:179
> >  iw_query_port drivers/infiniband/core/device.c:2049 [inline]
> >  ib_query_port drivers/infiniband/core/device.c:2090 [inline]
> >  ib_query_port+0x3d5/0x8a0 drivers/infiniband/core/device.c:2082
> >  ib_cache_update.part.0+0xdc/0xa30 drivers/infiniband/core/cache.c:1498
> >  ib_cache_update drivers/infiniband/core/cache.c:1572 [inline]
> >  ib_cache_event_task+0x1c2/0x290 drivers/infiniband/core/cache.c:1572
> >  process_one_work+0x9ac/0x1a60 kernel/workqueue.c:3254
> >  process_scheduled_works kernel/workqueue.c:3335 [inline]
> >  worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416
> >  kthread+0x2c4/0x3a0 kernel/kthread.c:388
> >  ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
> >  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
> >  </TASK>
> >
> > Allocated by task 10125:
> >  kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
> >  kasan_save_track+0x14/0x30 mm/kasan/common.c:68
> >  poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
> >  __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387
> >  kasan_kmalloc include/linux/kasan.h:211 [inline]
> >  __do_kmalloc_node mm/slub.c:3966 [inline]
> >  __kmalloc_node+0x226/0x480 mm/slub.c:3973
> >  kmalloc_node include/linux/slab.h:648 [inline]
> >  kvmalloc_node+0x9d/0x1a0 mm/util.c:634
> >  kvmalloc include/linux/slab.h:766 [inline]
> >  kvzalloc include/linux/slab.h:774 [inline]
> >  alloc_netdev_mqs+0xb3/0x12b0 net/core/dev.c:10840
> >  rtnl_create_link+0xc88/0xfa0 net/core/rtnetlink.c:3358
> >  rtnl_newlink_create net/core/rtnetlink.c:3484 [inline]
> >  __rtnl_newlink+0x10ae/0x1960 net/core/rtnetlink.c:3714
> >  rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3727
> >  rtnetlink_rcv_msg+0x3ca/0xe60 net/core/rtnetlink.c:6595
> >  netlink_rcv_skb+0x16e/0x440 net/netlink/af_netlink.c:2559
> >  netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
> >  netlink_unicast+0x545/0x820 net/netlink/af_netlink.c:1361
> >  netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1905
> >  sock_sendmsg_nosec net/socket.c:730 [inline]
> >  __sock_sendmsg net/socket.c:745 [inline]
> >  __sys_sendto+0x482/0x4e0 net/socket.c:2191
> >  __do_sys_sendto net/socket.c:2203 [inline]
> >  __se_sys_sendto net/socket.c:2199 [inline]
> >  __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2199
> >  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> >  do_syscall_64+0xd5/0x260 arch/x86/entry/common.c:83
> >  entry_SYSCALL_64_after_hwframe+0x6d/0x75
> >
> > Freed by task 61:
> >  kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
> >  kasan_save_track+0x14/0x30 mm/kasan/common.c:68
> >  kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
> >  poison_slab_object mm/kasan/common.c:240 [inline]
> >  __kasan_slab_free+0x11d/0x1a0 mm/kasan/common.c:256
> >  kasan_slab_free include/linux/kasan.h:184 [inline]
> >  slab_free_hook mm/slub.c:2106 [inline]
> >  slab_free mm/slub.c:4280 [inline]
> >  kfree+0x129/0x370 mm/slub.c:4390
> >  kvfree+0x47/0x50 mm/util.c:680
> >  device_release+0xa4/0x240 drivers/base/core.c:2499
> >  kobject_cleanup lib/kobject.c:689 [inline]
> >  kobject_release lib/kobject.c:720 [inline]
> >  kref_put include/linux/kref.h:65 [inline]
> >  kobject_put+0x1fd/0x5b0 lib/kobject.c:737
> >  netdev_run_todo+0x7d1/0x1260 net/core/dev.c:10591
> >  default_device_exit_batch+0x860/0xae0 net/core/dev.c:11632
> >  ops_exit_list+0x12b/0x180 net/core/net_namespace.c:175
> >  cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:637
> >  process_one_work+0x9ac/0x1a60 kernel/workqueue.c:3254
> >  process_scheduled_works kernel/workqueue.c:3335 [inline]
> >  worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416
> >  kthread+0x2c4/0x3a0 kernel/kthread.c:388
> >  ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
> >  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
> >
> > The buggy address belongs to the object at ffff888021f46000
> >  which belongs to the cache kmalloc-cg-4k of size 4096
> > The buggy address is located 776 bytes inside of
> >  freed 4096-byte region [ffff888021f46000, ffff888021f47000)
> >
> > The buggy address belongs to the physical page:
> > page:ffffea000087d000 refcount:1 mapcount:0 mapping:0000000000000000 in=
dex:0x0 pfn:0x21f40
> > head:ffffea000087d000 order:3 entire_mapcount:0 nr_pages_mapped:0 pinco=
unt:0
> > memcg:ffff8880636ce481
> > flags: 0xfff00000000840(slab|head|node=3D0|zone=3D1|lastcpupid=3D0x7ff)
> > page_type: 0xffffffff()
> > raw: 00fff00000000840 ffff88801504f500 dead000000000122 000000000000000=
0
> > raw: 0000000000000000 0000000000040004 00000001ffffffff ffff8880636ce48=
1
> > page dumped because: kasan: bad access detected
> > page_owner tracks the page as allocated
> > page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20=
c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC=
|__GFP_HARDWALL), pid 10125, tgid 10125 (syz-executor.2), ts 404185927295, =
free_ts 404019420685
> >  set_page_owner include/linux/page_owner.h:31 [inline]
> >  post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1533
> >  prep_new_page mm/page_alloc.c:1540 [inline]
> >  get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3311
> >  __alloc_pages+0x22b/0x2410 mm/page_alloc.c:4569
> >  __alloc_pages_node include/linux/gfp.h:238 [inline]
> >  alloc_pages_node include/linux/gfp.h:261 [inline]
> >  alloc_slab_page mm/slub.c:2175 [inline]
> >  allocate_slab mm/slub.c:2338 [inline]
> >  new_slab+0xcc/0x3a0 mm/slub.c:2391
> >  ___slab_alloc+0x66d/0x1790 mm/slub.c:3525
> >  __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3610
> >  __slab_alloc_node mm/slub.c:3663 [inline]
> >  slab_alloc_node mm/slub.c:3835 [inline]
> >  __do_kmalloc_node mm/slub.c:3965 [inline]
> >  __kmalloc_node_track_caller+0x367/0x470 mm/slub.c:3986
> >  kmemdup+0x29/0x60 mm/util.c:131
> >  kmemdup include/linux/fortify-string.h:738 [inline]
> >  __devinet_sysctl_register+0xbc/0x360 net/ipv4/devinet.c:2577
> >  devinet_sysctl_register net/ipv4/devinet.c:2629 [inline]
> >  devinet_sysctl_register+0x17b/0x200 net/ipv4/devinet.c:2619
> >  inetdev_init+0x28b/0x580 net/ipv4/devinet.c:286
> >  inetdev_event+0xd23/0x19b0 net/ipv4/devinet.c:1560
> >  notifier_call_chain+0xbc/0x3e0 kernel/notifier.c:93
> >  call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1950
> >  call_netdevice_notifiers_extack net/core/dev.c:1988 [inline]
> >  call_netdevice_notifiers net/core/dev.c:2002 [inline]
> >  register_netdevice+0x15f5/0x1ca0 net/core/dev.c:10307
> >  virt_wifi_newlink+0x3ed/0x970 drivers/net/wireless/virtual/virt_wifi.c=
:553
> > page last free pid 10234 tgid 10232 stack trace:
> >  reset_page_owner include/linux/page_owner.h:24 [inline]
> >  free_pages_prepare mm/page_alloc.c:1140 [inline]
> >  free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2346
> >  free_unref_page+0x33/0x3c0 mm/page_alloc.c:2486
> >  __put_partials+0x14c/0x170 mm/slub.c:2906
> >  qlink_free mm/kasan/quarantine.c:163 [inline]
> >  qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
> >  kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
> >  __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
> >  kasan_slab_alloc include/linux/kasan.h:201 [inline]
> >  slab_post_alloc_hook mm/slub.c:3798 [inline]
> >  slab_alloc_node mm/slub.c:3845 [inline]
> >  kmem_cache_alloc_node+0x177/0x340 mm/slub.c:3888
> >  __alloc_skb+0x2b1/0x380 net/core/skbuff.c:658
> >  alloc_skb_fclone include/linux/skbuff.h:1368 [inline]
> >  tipc_buf_acquire+0x26/0xe0 net/tipc/msg.c:72
> >  tipc_msg_build+0x10c/0x1120 net/tipc/msg.c:386
> >  tipc_sendmcast+0x79e/0xb70 net/tipc/socket.c:881
> >  __tipc_sendmsg+0x1317/0x1940 net/tipc/socket.c:1469
> >  tipc_sendmsg+0x4f/0x70 net/tipc/socket.c:1403
> >  sock_sendmsg_nosec net/socket.c:730 [inline]
> >  __sock_sendmsg net/socket.c:745 [inline]
> >  ____sys_sendmsg+0xab8/0xc90 net/socket.c:2584
> >  ___sys_sendmsg+0x135/0x1e0 net/socket.c:2638
> >  __sys_sendmmsg+0x1a1/0x450 net/socket.c:2724
> >
> > Memory state around the buggy address:
> >  ffff888021f46200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> >  ffff888021f46280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> >> ffff888021f46300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> >                       ^
> >  ffff888021f46380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> >  ffff888021f46400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> > BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x165/0=
x190 net/ethtool/ioctl.c:445
> > Read of size 8 at addr ffff888021f46308 by task kworker/0:4/5169
> >
> > CPU: 0 PID: 5169 Comm: kworker/0:4 Tainted: G    B              6.8.0-s=
yzkaller-05562-g61387b8dcf1d #0
> > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS=
 Google 02/29/2024
> > Workqueue: infiniband ib_cache_event_task
> > Call Trace:
> >  <TASK>
> >  __dump_stack lib/dump_stack.c:88 [inline]
> >  dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
> >  print_address_description mm/kasan/report.c:377 [inline]
> >  print_report+0xc3/0x620 mm/kasan/report.c:488
> >  kasan_report+0xd9/0x110 mm/kasan/report.c:601
> >  __ethtool_get_link_ksettings+0x165/0x190 net/ethtool/ioctl.c:445
> >  __ethtool_get_link_ksettings+0xf5/0x190 net/ethtool/ioctl.c:445
> >  ib_get_eth_speed+0x123/0xb50 drivers/infiniband/core/verbs.c:1984
> >  siw_query_port+0x3c/0x3e0 drivers/infiniband/sw/siw/siw_verbs.c:179
> >  iw_query_port drivers/infiniband/core/device.c:2049 [inline]
> >  ib_query_port drivers/infiniband/core/device.c:2090 [inline]
> >  ib_query_port+0x3d5/0x8a0 drivers/infiniband/core/device.c:2082
> >  ib_cache_update.part.0+0xdc/0xa30 drivers/infiniband/core/cache.c:1498
> >  ib_cache_update drivers/infiniband/core/cache.c:1572 [inline]
> >  ib_cache_event_task+0x1c2/0x290 drivers/infiniband/core/cache.c:1572
> >  process_one_work+0x9ac/0x1a60 kernel/workqueue.c:3254
> >  process_scheduled_works kernel/workqueue.c:3335 [inline]
> >  worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416
> >  kthread+0x2c4/0x3a0 kernel/kthread.c:388
> >  ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
> >  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
> >  </TASK>
> >
> > Allocated by task 10125:
> >  kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
> >  kasan_save_track+0x14/0x30 mm/kasan/common.c:68
> >  poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
> >  __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387
> >  kasan_kmalloc include/linux/kasan.h:211 [inline]
> >  __do_kmalloc_node mm/slub.c:3966 [inline]
> >  __kmalloc_node+0x226/0x480 mm/slub.c:3973
> >  kmalloc_node include/linux/slab.h:648 [inline]
> >  kvmalloc_node+0x9d/0x1a0 mm/util.c:634
> >  kvmalloc include/linux/slab.h:766 [inline]
> >  kvzalloc include/linux/slab.h:774 [inline]
> >  alloc_netdev_mqs+0xb3/0x12b0 net/core/dev.c:10840
> >  rtnl_create_link+0xc88/0xfa0 net/core/rtnetlink.c:3358
> >  rtnl_newlink_create net/core/rtnetlink.c:3484 [inline]
> >  __rtnl_newlink+0x10ae/0x1960 net/core/rtnetlink.c:3714
> >  rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3727
> >  rtnetlink_rcv_msg+0x3ca/0xe60 net/core/rtnetlink.c:6595
> >  netlink_rcv_skb+0x16e/0x440 net/netlink/af_netlink.c:2559
> >  netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
> >  netlink_unicast+0x545/0x820 net/netlink/af_netlink.c:1361
> >  netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1905
> >  sock_sendmsg_nosec net/socket.c:730 [inline]
> >  __sock_sendmsg net/socket.c:745 [inline]
> >  __sys_sendto+0x482/0x4e0 net/socket.c:2191
> >  __do_sys_sendto net/socket.c:2203 [inline]
> >  __se_sys_sendto net/socket.c:2199 [inline]
> >  __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2199
> >  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> >  do_syscall_64+0xd5/0x260 arch/x86/entry/common.c:83
> >  entry_SYSCALL_64_after_hwframe+0x6d/0x75
> >
> > Freed by task 61:
> >  kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
> >  kasan_save_track+0x14/0x30 mm/kasan/common.c:68
> >  kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
> >  poison_slab_object mm/kasan/common.c:240 [inline]
> >  __kasan_slab_free+0x11d/0x1a0 mm/kasan/common.c:256
> >  kasan_slab_free include/linux/kasan.h:184 [inline]
> >  slab_free_hook mm/slub.c:2106 [inline]
> >  slab_free mm/slub.c:4280 [inline]
> >  kfree+0x129/0x370 mm/slub.c:4390
> >  kvfree+0x47/0x50 mm/util.c:680
> >  device_release+0xa4/0x240 drivers/base/core.c:2499
> >  kobject_cleanup lib/kobject.c:689 [inline]
> >  kobject_release lib/kobject.c:720 [inline]
> >  kref_put include/linux/kref.h:65 [inline]
> >  kobject_put+0x1fd/0x5b0 lib/kobject.c:737
> >  netdev_run_todo+0x7d1/0x1260 net/core/dev.c:10591
> >  default_device_exit_batch+0x860/0xae0 net/core/dev.c:11632
> >  ops_exit_list+0x12b/0x180 net/core/net_namespace.c:175
> >  cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:637
> >  process_one_work+0x9ac/0x1a60 kernel/workqueue.c:3254
> >  process_scheduled_works kernel/workqueue.c:3335 [inline]
> >  worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416
> >  kthread+0x2c4/0x3a0 kernel/kthread.c:388
> >  ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
> >  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
> >
> > The buggy address belongs to the object at ffff888021f46000
> >  which belongs to the cache kmalloc-cg-4k of size 4096
> > The buggy address is located 776 bytes inside of
> >  freed 4096-byte region [ffff888021f46000, ffff888021f47000)
> >
> > The buggy address belongs to the physical page:
> > page:ffffea000087d000 refcount:1 mapcount:0 mapping:0000000000000000 in=
dex:0x0 pfn:0x21f40
> > head:ffffea000087d000 order:3 entire_mapcount:0 nr_pages_mapped:0 pinco=
unt:0
> > memcg:ffff8880636ce481
> > flags: 0xfff00000000840(slab|head|node=3D0|zone=3D1|lastcpupid=3D0x7ff)
> > page_type: 0xffffffff()
> > raw: 00fff00000000840 ffff88801504f500 dead000000000122 000000000000000=
0
> > raw: 0000000000000000 0000000000040004 00000001ffffffff ffff8880636ce48=
1
> > page dumped because: kasan: bad access detected
> > page_owner tracks the page as allocated
> > page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20=
c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC=
|__GFP_HARDWALL), pid 10125, tgid 10125 (syz-executor.2), ts 404185927295, =
free_ts 404019420685
> >  set_page_owner include/linux/page_owner.h:31 [inline]
> >  post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1533
> >  prep_new_page mm/page_alloc.c:1540 [inline]
> >  get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3311
> >  __alloc_pages+0x22b/0x2410 mm/page_alloc.c:4569
> >  __alloc_pages_node include/linux/gfp.h:238 [inline]
> >  alloc_pages_node include/linux/gfp.h:261 [inline]
> >  alloc_slab_page mm/slub.c:2175 [inline]
> >  allocate_slab mm/slub.c:2338 [inline]
> >  new_slab+0xcc/0x3a0 mm/slub.c:2391
> >  ___slab_alloc+0x66d/0x1790 mm/slub.c:3525
> >  __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3610
> >  __slab_alloc_node mm/slub.c:3663 [inline]
> >  slab_alloc_node mm/slub.c:3835 [inline]
> >  __do_kmalloc_node mm/slub.c:3965 [inline]
> >  __kmalloc_node_track_caller+0x367/0x470 mm/slub.c:3986
> >  kmemdup+0x29/0x60 mm/util.c:131
> >  kmemdup include/linux/fortify-string.h:738 [inline]
> >  __devinet_sysctl_register+0xbc/0x360 net/ipv4/devinet.c:2577
> >  devinet_sysctl_register net/ipv4/devinet.c:2629 [inline]
> >  devinet_sysctl_register+0x17b/0x200 net/ipv4/devinet.c:2619
> >  inetdev_init+0x28b/0x580 net/ipv4/devinet.c:286
> >  inetdev_event+0xd23/0x19b0 net/ipv4/devinet.c:1560
> >  notifier_call_chain+0xbc/0x3e0 kernel/notifier.c:93
> >  call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1950
> >  call_netdevice_notifiers_extack net/core/dev.c:1988 [inline]
> >  call_netdevice_notifiers net/core/dev.c:2002 [inline]
> >  register_netdevice+0x15f5/0x1ca0 net/core/dev.c:10307
> >  virt_wifi_newlink+0x3ed/0x970 drivers/net/wireless/virtual/virt_wifi.c=
:553
> > page last free pid 10234 tgid 10232 stack trace:
> >  reset_page_owner include/linux/page_owner.h:24 [inline]
> >  free_pages_prepare mm/page_alloc.c:1140 [inline]
> >  free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2346
> >  free_unref_page+0x33/0x3c0 mm/page_alloc.c:2486
> >  __put_partials+0x14c/0x170 mm/slub.c:2906
> >  qlink_free mm/kasan/quarantine.c:163 [inline]
> >  qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
> >  kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
> >  __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
> >  kasan_slab_alloc include/linux/kasan.h:201 [inline]
> >  slab_post_alloc_hook mm/slub.c:3798 [inline]
> >  slab_alloc_node mm/slub.c:3845 [inline]
> >  kmem_cache_alloc_node+0x177/0x340 mm/slub.c:3888
> >  __alloc_skb+0x2b1/0x380 net/core/skbuff.c:658
> >  alloc_skb_fclone include/linux/skbuff.h:1368 [inline]
> >  tipc_buf_acquire+0x26/0xe0 net/tipc/msg.c:72
> >  tipc_msg_build+0x10c/0x1120 net/tipc/msg.c:386
> >  tipc_sendmcast+0x79e/0xb70 net/tipc/socket.c:881
> >  __tipc_sendmsg+0x1317/0x1940 net/tipc/socket.c:1469
> >  tipc_sendmsg+0x4f/0x70 net/tipc/socket.c:1403
> >  sock_sendmsg_nosec net/socket.c:730 [inline]
> >  __sock_sendmsg net/socket.c:745 [inline]
> >  ____sys_sendmsg+0xab8/0xc90 net/socket.c:2584
> >  ___sys_sendmsg+0x135/0x1e0 net/socket.c:2638
> >  __sys_sendmmsg+0x1a1/0x450 net/socket.c:2724
> >
> > Memory state around the buggy address:
> >  ffff888021f46200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> >  ffff888021f46280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> >> ffff888021f46300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> >                       ^
> >  ffff888021f46380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> >  ffff888021f46400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> >
> >
> > ---
> > This report is generated by a bot. It may contain errors.
> > See https://goo.gl/tpsmEJ for more information about syzbot.
> > syzbot engineers can be reached at syzkaller@googlegroups.com.
> >
> > syzbot will keep track of this issue. See:
> > https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> >
> > If the report is already addressed, let syzbot know by replying with:
> > #syz fix: exact-commit-title
> >
> > If you want to overwrite report's subsystems, reply with:
> > #syz set subsystems: new-subsystem
> > (See the list of subsystem names on the web dashboard)
> >
> > If the report is a duplicate of another one, reply with:
> > #syz dup: exact-subject-of-another-report
> >
> > If you want to undo deduplication, reply with:
> > #syz undup
> >