Subject: kernel BUG at net/key/af_key.c:LINE!

From: syzbot <[email-masked]>
Date: Tue, 24 Oct 2017 08:08:31 -0700

Hello,

syzkaller hit the following crash on  
02a2b05395dde2f49e7777b67b51a5fbc6606943
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.
C reproducer is attached
syzkaller reproducer is attached. See https://goo.gl/kgGztJ
for information about syzkaller reproducers

------------[ cut here ]------------
kernel BUG at net/key/af_key.c:2068!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
    (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 3024 Comm: syzkaller790413 Not tainted 4.14.0-rc2+ #16
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
task: ffff8801cddc8100 task.stack: ffff8801c0a88000
RIP: 0010:pfkey_xfrm_policy2msg+0x209c/0x22b0 net/key/af_key.c:2068
RSP: 0018:ffff8801c0a8f318 EFLAGS: 00010297
RAX: ffff8801cddc8100 RBX: ffff8801cea778cc RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000000000000204e RDI: ffff8801cea7776c
RBP: ffff8801c0a8f3f0 R08: 0000000000000001 R09: ffff8801d0b66dc0
R10: 000000000000001b R11: ffffed003a16cdd2 R12: ffff8801cea77788
R13: ffff8801cea77680 R14: 0000000000000008 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8801db200000(0063) knlGS:00000000ecf1fb40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000020002ff0 CR3: 00000001d4b3c000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  dump_sp+0x14f/0x510 net/key/af_key.c:2669
  xfrm_policy_walk+0x2f1/0xa30 net/xfrm/xfrm_policy.c:1015
  pfkey_dump_sp+0x42/0x50 net/key/af_key.c:2692
  pfkey_do_dump+0xaa/0x3f0 net/key/af_key.c:299
  pfkey_spddump+0x1a0/0x210 net/key/af_key.c:2719
  pfkey_process+0x60b/0x720 net/key/af_key.c:2809
  pfkey_sendmsg+0x4d6/0x9f0 net/key/af_key.c:3648
  sock_sendmsg_nosec net/socket.c:633 [inline]
  sock_sendmsg+0xca/0x110 net/socket.c:643
  sock_write_iter+0x320/0x5e0 net/socket.c:912
  call_write_iter include/linux/fs.h:1770 [inline]
  new_sync_write fs/read_write.c:468 [inline]
  __vfs_write+0x68a/0x970 fs/read_write.c:481
  vfs_write+0x18f/0x510 fs/read_write.c:543
  SYSC_write fs/read_write.c:588 [inline]
  SyS_write+0xef/0x220 fs/read_write.c:580
  do_syscall_32_irqs_on arch/x86/entry/common.c:329 [inline]
  do_fast_syscall_32+0x3f2/0xf05 arch/x86/entry/common.c:391
  entry_SYSENTER_compat+0x51/0x60 arch/x86/entry/entry_64_compat.S:124
RIP: 0023:0xf7f39c79
RSP: 002b:00000000ecf1f1ec EFLAGS: 00000297 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 0000000020002ff0
RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Code: ff ff 48 89 95 58 ff ff ff 89 8d 70 ff ff ff e8 ab 90 5f fd 48 8b 95  
58 ff ff ff 8b 8d 70 ff ff ff e9 04 e3 ff ff e8 54 d2 2a fd <0f> 0b be 02  
00 00 00 4c 89 f7 e8 c5 91 5f fd e9 6f e3 ff ff 48
RIP: pfkey_xfrm_policy2msg+0x209c/0x22b0 net/key/af_key.c:2068 RSP:  
ffff8801c0a8f318
---[ end trace 5d48d18d4a6d272b ]---

---
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