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BUG: KASAN: use-after-free in dev_put include/linux/netdevice.h:3676 [inline]
BUG: KASAN: use-after-free in netdevice_event_work_handler+0x15b/0x1b0 drivers/infiniband/core/roce_gid_mgmt.c:626
Read of size 8 at addr ffff888098ba29c0 by task kworker/u4:5/2964

CPU: 1 PID: 2964 Comm: kworker/u4:5 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Workqueue: gid-cache-wq netdevice_event_work_handler
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433
 dev_put include/linux/netdevice.h:3676 [inline]
 netdevice_event_work_handler+0x15b/0x1b0 drivers/infiniband/core/roce_gid_mgmt.c:626
 process_one_work+0x864/0x1570 kernel/workqueue.c:2153
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Allocated by task 21500:
 __do_kmalloc_node mm/slab.c:3689 [inline]
 __kmalloc_node+0x4c/0x70 mm/slab.c:3696
 kmalloc_node include/linux/slab.h:557 [inline]
 kvmalloc_node+0x61/0xf0 mm/util.c:423
 kvmalloc include/linux/mm.h:577 [inline]
 kvzalloc include/linux/mm.h:585 [inline]
 alloc_netdev_mqs+0x97/0xd50 net/core/dev.c:9152
 __ip_tunnel_create+0x201/0x580 net/ipv4/ip_tunnel.c:267
 ip_tunnel_init_net+0x330/0x990 net/ipv4/ip_tunnel.c:1035
 ops_init+0xb3/0x410 net/core/net_namespace.c:129
 setup_net+0x2c2/0x720 net/core/net_namespace.c:316
 copy_net_ns+0x1f7/0x340 net/core/net_namespace.c:439
 create_new_namespaces+0x3f6/0x7b0 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:206
 ksys_unshare+0x36c/0x9a0 kernel/fork.c:2542
 __do_sys_unshare kernel/fork.c:2610 [inline]
 __se_sys_unshare kernel/fork.c:2608 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2608
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 21500:
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcc/0x210 mm/slab.c:3822
 kvfree+0x59/0x60 mm/util.c:452
 device_release+0x76/0x210 drivers/base/core.c:1076
 kobject_cleanup lib/kobject.c:662 [inline]
 kobject_release lib/kobject.c:691 [inline]
 kref_put include/linux/kref.h:70 [inline]
 kobject_put+0x28b/0x5d0 lib/kobject.c:708
 put_device+0x1c/0x30 drivers/base/core.c:2267
 free_netdev+0x309/0x410 net/core/dev.c:9265
 __ip_tunnel_create+0x48f/0x580 net/ipv4/ip_tunnel.c:287
 ip_tunnel_init_net+0x330/0x990 net/ipv4/ip_tunnel.c:1035
 ops_init+0xb3/0x410 net/core/net_namespace.c:129
 setup_net+0x2c2/0x720 net/core/net_namespace.c:316
 copy_net_ns+0x1f7/0x340 net/core/net_namespace.c:439
 create_new_namespaces+0x3f6/0x7b0 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:206
 ksys_unshare+0x36c/0x9a0 kernel/fork.c:2542
 __do_sys_unshare kernel/fork.c:2610 [inline]
 __se_sys_unshare kernel/fork.c:2608 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2608
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff888098ba2480
 which belongs to the cache kmalloc-4096 of size 4096
The buggy address is located 1344 bytes inside of
 4096-byte region [ffff888098ba2480, ffff888098ba3480)
The buggy address belongs to the page:
page:ffffea000262e880 count:1 mapcount:0 mapping:ffff88813bff0dc0 index:0x0 compound_mapcount: 0
flags: 0xfff00000008100(slab|head)
raw: 00fff00000008100 ffffea0001382688 ffffea000259b288 ffff88813bff0dc0
raw: 0000000000000000 ffff888098ba2480 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888098ba2880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888098ba2900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888098ba2980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff888098ba2a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888098ba2a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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