------------[ cut here ]------------
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 0 PID: 21002 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Modules linked in:
CPU: 0 PID: 21002 Comm: syz-executor.1 Not tainted 5.12.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Code: 1d 3b 53 e8 09 31 ff 89 de e8 fd e7 aa fd 84 db 75 e0 e8 44 e1 aa fd 48 c7 c7 a0 e8 c1 89 c6 05 1b 53 e8 09 01 e8 0e d8 fa 04 <0f> 0b eb c4 e8 28 e1 aa fd 0f b6 1d 0a 53 e8 09 31 ff 89 de e8 c8
RSP: 0018:ffffc90015d07a70 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000040000 RSI: ffffffff815c4d85 RDI: fffff52002ba0f40
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815bdb1e R11: 0000000000000000 R12: ffff88806048a568
R13: ffff88806048ac00 R14: ffff88802fcfa800 R15: ffff88801de91dc0
FS:  00007f3180ca2700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f20153fe018 CR3: 000000002cffd000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 __refcount_dec include/linux/refcount.h:344 [inline]
 refcount_dec include/linux/refcount.h:359 [inline]
 dev_put include/linux/netdevice.h:4135 [inline]
 ip6gre_tunnel_uninit+0x3d7/0x440 net/ipv6/ip6_gre.c:420
 register_netdevice+0xadf/0x1500 net/core/dev.c:10308
 ip6gre_tunnel_locate net/ipv6/ip6_gre.c:381 [inline]
 ip6gre_tunnel_ioctl+0x1087/0x1720 net/ipv6/ip6_gre.c:1298
 dev_do_ioctl net/core/dev_ioctl.c:230 [inline]
 dev_ifsioc+0x90d/0xa60 net/core/dev_ioctl.c:336
 dev_ioctl+0x277/0xb70 net/core/dev_ioctl.c:530
 sock_ioctl+0x50d/0x6a0 net/socket.c:1104
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x466459
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3180ca2188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 0000000020000000 RSI: 00000000000089f1 RDI: 0000000000000003
RBP: 00007f3180ca21d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ffe5b8fd8bf R14: 00007f3180ca2300 R15: 0000000000022000