------------[ cut here ]------------ refcount_t: increment on 0; use-after-free. WARNING: CPU: 0 PID: 32713 at lib/refcount.c:156 refcount_inc_checked lib/refcount.c:156 [inline] WARNING: CPU: 0 PID: 32713 at lib/refcount.c:156 refcount_inc_checked+0x61/0x70 lib/refcount.c:154 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 32713 Comm: syz-executor.4 Not tainted 5.3.0-rc1+ #87 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 panic+0x2dc/0x755 kernel/panic.c:219 __warn.cold+0x20/0x4c kernel/panic.c:576 report_bug+0x263/0x2b0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:179 [inline] fixup_bug arch/x86/kernel/traps.c:174 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1026 RIP: 0010:refcount_inc_checked lib/refcount.c:156 [inline] RIP: 0010:refcount_inc_checked+0x61/0x70 lib/refcount.c:154 Code: 1d ed 9b 64 06 31 ff 89 de e8 8b a3 35 fe 84 db 75 dd e8 42 a2 35 fe 48 c7 c7 80 03 c6 87 c6 05 cd 9b 64 06 01 e8 17 0f 07 fe <0f> 0b eb c1 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57 41 RSP: 0018:ffff8880ae809bf0 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000100 RSI: ffffffff815c51f6 RDI: ffffed1015d01370 RBP: ffff8880ae809c00 R08: ffff888058fa8300 R09: fffffbfff11b42a5 R10: fffffbfff11b42a4 R11: ffffffff88da1523 R12: ffff888090498600 R13: ffff8880904985e8 R14: ffff8880923ef5c8 R15: ffff8880923ef5a0 sock_hold include/net/sock.h:649 [inline] sk_add_node include/net/sock.h:701 [inline] nr_insert_socket+0x2d/0xe0 net/netrom/af_netrom.c:137 nr_rx_frame+0x1605/0x1e73 net/netrom/af_netrom.c:1023 nr_loopback_timer+0x7b/0x170 net/netrom/nr_loopback.c:59 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1322 expire_timers kernel/time/timer.c:1366 [inline] __run_timers kernel/time/timer.c:1685 [inline] __run_timers kernel/time/timer.c:1653 [inline] run_timer_softirq+0x697/0x17a0 kernel/time/timer.c:1698 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:537 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1095 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:828 RIP: 0010:stack_trace_save+0xc1/0xe0 kernel/stacktrace.c:125 Code: 48 8b 14 25 40 fe 01 00 44 89 6d 88 44 89 65 8c e8 b4 7f c8 ff 8b 45 90 48 c7 03 00 00 00 00 c7 43 08 00 00 00 00 48 8b 4d d8 <65> 48 33 0c 25 28 00 00 00 75 0d 48 83 ec 80 5b 41 5c 41 5d 41 5e RSP: 0018:ffff88805c2ff350 EFLAGS: 00000292 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000019 RBX: ffffed100b85fe6a RCX: e98dc53e7d81eb00 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000286 RBP: ffff88805c2ff3f0 R08: 1ffffffff134addf R09: fffffbfff134ade0 R10: fffffbfff134addf R11: ffffffff89a56eff R12: 0000000000000001 R13: 0000000000000040 R14: ffff88805c2ff400 R15: ffff8880aa400e00 save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc mm/kasan/common.c:487 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:460 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:501 kmem_cache_alloc_node_trace+0x15a/0x750 mm/slab.c:3594 __do_kmalloc_node mm/slab.c:3614 [inline] __kmalloc_node_track_caller+0x3d/0x70 mm/slab.c:3629 __kmalloc_reserve.isra.0+0x40/0xf0 net/core/skbuff.c:141 pskb_expand_head+0x151/0xe00 net/core/skbuff.c:1628 netlink_trim+0x218/0x270 net/netlink/af_netlink.c:1284 netlink_broadcast_filtered+0x68/0xb90 net/netlink/af_netlink.c:1489 netlink_broadcast net/netlink/af_netlink.c:1534 [inline] nlmsg_multicast include/net/netlink.h:969 [inline] nlmsg_notify+0x93/0x1c0 net/netlink/af_netlink.c:2520 rtnl_notify net/core/rtnetlink.c:737 [inline] rtmsg_ifinfo_send net/core/rtnetlink.c:3492 [inline] rtmsg_ifinfo_event.part.0+0xb0/0xe0 net/core/rtnetlink.c:3507 rtmsg_ifinfo_event net/core/rtnetlink.c:3515 [inline] rtmsg_ifinfo+0x8d/0xa0 net/core/rtnetlink.c:3513 register_netdevice+0xb51/0xf10 net/core/dev.c:8764 __ip_tunnel_create+0x36b/0x530 net/ipv4/ip_tunnel.c:269 ip_tunnel_init_net+0x375/0x9e0 net/ipv4/ip_tunnel.c:1060 ipgre_tap_init_net+0x2a/0x30 net/ipv4/ip_gre.c:1572 ops_init+0xb3/0x420 net/core/net_namespace.c:137 setup_net+0x2d2/0x890 net/core/net_namespace.c:334 copy_net_ns+0x290/0x41f net/core/net_namespace.c:475 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:103 unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:202 ksys_unshare+0x444/0x980 kernel/fork.c:2831 __do_sys_unshare kernel/fork.c:2899 [inline] __se_sys_unshare kernel/fork.c:2897 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2897 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459829 Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f21b0acdc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000459829 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f21b0ace6d4 R13: 00000000004c8f0a R14: 00000000004dff80 R15: 00000000ffffffff Kernel Offset: disabled Rebooting in 86400 seconds..