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BUG: KASAN: use-after-free in dev_put include/linux/netdevice.h:3975 [inline]
BUG: KASAN: use-after-free in netdevice_event_work_handler+0x15b/0x1b0 drivers/infiniband/core/roce_gid_mgmt.c:630
Read of size 8 at addr ffff88805fdfc568 by task kworker/u4:8/12719

CPU: 0 PID: 12719 Comm: kworker/u4:8 Not tainted 5.10.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: gid-cache-wq netdevice_event_work_handler
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xae/0x4c8 mm/kasan/report.c:385
 __kasan_report mm/kasan/report.c:545 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:562
 dev_put include/linux/netdevice.h:3975 [inline]
 netdevice_event_work_handler+0x15b/0x1b0 drivers/infiniband/core/roce_gid_mgmt.c:630
 process_one_work+0x933/0x15a0 kernel/workqueue.c:2272
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2418
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Allocated by task 19002:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:461
 kmalloc_node include/linux/slab.h:575 [inline]
 kvmalloc_node+0x61/0xf0 mm/util.c:575
 kvmalloc include/linux/mm.h:765 [inline]
 kvzalloc include/linux/mm.h:773 [inline]
 alloc_netdev_mqs+0x97/0xe70 net/core/dev.c:10452
 __ip_tunnel_create+0x201/0x580 net/ipv4/ip_tunnel.c:254
 ip_tunnel_init_net+0x330/0x9d0 net/ipv4/ip_tunnel.c:1063
 ops_init+0xaf/0x470 net/core/net_namespace.c:152
 setup_net+0x2d8/0x850 net/core/net_namespace.c:342
 copy_net_ns+0x2cf/0x5e0 net/core/net_namespace.c:483
 create_new_namespaces+0x3f6/0xb10 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:231
 ksys_unshare+0x445/0x8e0 kernel/fork.c:2949
 __do_sys_unshare kernel/fork.c:3017 [inline]
 __se_sys_unshare kernel/fork.c:3015 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3015
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 19002:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56
 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355
 __kasan_slab_free+0x102/0x140 mm/kasan/common.c:422
 slab_free_hook mm/slub.c:1544 [inline]
 slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1577
 slab_free mm/slub.c:3142 [inline]
 kfree+0xdb/0x360 mm/slub.c:4124
 kvfree+0x42/0x50 mm/util.c:604
 device_release+0x9f/0x240 drivers/base/core.c:1806
 kobject_cleanup lib/kobject.c:705 [inline]
 kobject_release lib/kobject.c:736 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x1c8/0x540 lib/kobject.c:753
 put_device+0x1b/0x30 drivers/base/core.c:3035
 free_netdev+0x3a2/0x4c0 net/core/dev.c:10572
 __ip_tunnel_create+0x48f/0x580 net/ipv4/ip_tunnel.c:274
 ip_tunnel_init_net+0x330/0x9d0 net/ipv4/ip_tunnel.c:1063
 ops_init+0xaf/0x470 net/core/net_namespace.c:152
 setup_net+0x2d8/0x850 net/core/net_namespace.c:342
 copy_net_ns+0x2cf/0x5e0 net/core/net_namespace.c:483
 create_new_namespaces+0x3f6/0xb10 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:231
 ksys_unshare+0x445/0x8e0 kernel/fork.c:2949
 __do_sys_unshare kernel/fork.c:3017 [inline]
 __se_sys_unshare kernel/fork.c:3015 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3015
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff88805fdfc000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 1384 bytes inside of
 4096-byte region [ffff88805fdfc000, ffff88805fdfd000)
The buggy address belongs to the page:
page:000000004fc278ce refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5fdf8
head:000000004fc278ce order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010042140
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88805fdfc400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805fdfc480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805fdfc500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                          ^
 ffff88805fdfc580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805fdfc600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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