TITLE: kernel BUG in ucma_join_ip_multicast
TYPE: BUG

[   24.127473] ------------[ cut here ]------------
[   24.132205] kernel BUG at lib/string.c:1052!
[   24.136804] invalid opcode: 0000 [#1] SMP KASAN
[   24.141458] Dumping ftrace buffer:
[   24.144969]    (ftrace buffer empty)
[   24.148648] Modules linked in:
[   24.151812] CPU: 1 PID: 4265 Comm: syzkaller394057 Not tainted 4.16.0-rc7+ #369
[   24.159224] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   24.168557] RIP: 0010:fortify_panic+0x13/0x20
[   24.173027] RSP: 0018:ffff8801c0baf940 EFLAGS: 00010282
[   24.178360] RAX: 0000000000000022 RBX: 1ffff10038175f2d RCX: 0000000000000000
[   24.185602] RDX: 0000000000000022 RSI: 1ffff10038175edd RDI: ffffed0038175f1c
[   24.192840] RBP: ffff8801c0baf940 R08: 0000000000000000 R09: 0000000000000000
[   24.200078] R10: 0000000000000006 R11: 0000000000000000 R12: ffff8801c0baf9e8
[   24.207319] R13: ffff8801c0baf988 R14: ffff8801c0bafaa8 R15: 000000000000fa00
[   24.214574] FS:  00000000019a4880(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
[   24.222770] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   24.228621] CR2: 0000000020000140 CR3: 00000001c12ff001 CR4: 00000000001606e0
[   24.235864] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   24.243106] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   24.250369] Call Trace:
[   24.252932]  ucma_join_ip_multicast+0x37a/0x3c0
[   24.274583]  ucma_write+0x2d6/0x3d0
[   24.290464]  __vfs_write+0xef/0x970
[   24.317834]  vfs_write+0x189/0x510
[   24.321347]  SyS_write+0xef/0x220
[   24.339418]  do_syscall_64+0x281/0x940
[   24.377156]  entry_SYSCALL_64_after_hwframe+0x42/0xb7
[   24.382312] RIP: 0033:0x43fd29
[   24.385470] RSP: 002b:00007ffff57bdc78 EFLAGS: 00000213 ORIG_RAX: 0000000000000001
[   24.393148] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fd29
[   24.400388] RDX: 0000000000000118 RSI: 0000000020000f80 RDI: 0000000000000003
[   24.407629] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
[   24.414866] R10: 00000000004002c8 R11: 0000000000000213 R12: 0000000000401650
[   24.422117] R13: 00000000004016e0 R14: 0000000000000000 R15: 0000000000000000
[   24.429384] Code: 08 5b 41 5c 41 5d 41 5e 41 5f 5d c3 0f 0b 48 89 df e8 d2 a7 3f fb eb de 55 48 89 fe 48 c7 c7 c0 43 44 87 48 89 e5 e8 d5 05 f1 fa <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57 41 56 
[   24.448565] RIP: fortify_panic+0x13/0x20 RSP: ffff8801c0baf940
[   24.454568] ---[ end trace 1b9f94576855f965 ]---
