Subject: general protection fault in copy_verifier_state

From: syzbot <[email-masked]>
Date: Tue, 02 Jan 2018 14:58:01 -0800

Hello,

syzkaller hit the following crash on  
6bb8824732f69de0f233ae6b1a8158e149627b38
git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.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

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Reported-by: [email-masked]
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R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff
R13: 656c6c616b7a7973 R14: 000000000000000e R15: 0000000000000000
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
    (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 3197 Comm: syzkaller425062 Not tainted 4.15.0-rc5+ #170
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RIP: 0010:copy_func_state kernel/bpf/verifier.c:403 [inline]
RIP: 0010:copy_verifier_state+0x364/0x590 kernel/bpf/verifier.c:431
RSP: 0018:ffff8801c7fff130 EFLAGS: 00010203
RAX: 0000000000000070 RBX: dffffc0000000000 RCX: 0000000000000384
RDX: 0000000000000000 RSI: ffff8801c938d800 RDI: ffff8801c938d800
RBP: ffff8801c7fff188 R08: ffff8801c938d700 R09: ffff8801c938d700
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801c8066940
R13: ffff8801c938d700 R14: 0000000000000000 R15: ffff8801c938d800
FS:  0000000001581880(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020a97000 CR3: 00000001c839a001 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  pop_stack+0x8c/0x270 kernel/bpf/verifier.c:449
  push_stack kernel/bpf/verifier.c:491 [inline]
  check_cond_jmp_op kernel/bpf/verifier.c:3598 [inline]
  do_check+0x4b60/0xa050 kernel/bpf/verifier.c:4731
  bpf_check+0x3296/0x58c0 kernel/bpf/verifier.c:5489
  bpf_prog_load+0xa2a/0x1b00 kernel/bpf/syscall.c:1198
  SYSC_bpf kernel/bpf/syscall.c:1807 [inline]
  SyS_bpf+0x1044/0x4420 kernel/bpf/syscall.c:1769
  entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x4404f9
RSP: 002b:00007fff03dc4a48 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00000000004404f9
RDX: 0000000000000048 RSI: 0000000020903000 RDI: 0000000000000005
RBP: 000000000000000f R08: 0000000000000002 R09: 0000000000003332
R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff
R13: 656c6c616b7a7973 R14: 000000000000000e R15: 0000000000000000
Code: 4b 8d 3c f7 48 89 f8 48 c1 e8 03 80 3c 18 00 0f 85 05 02 00 00 4f 8b  
34 f7 49 8d 8e 84 03 00 00 48 89 c8 48 89 4d c8 48 c1 e8 03 <0f> b6 14 18  
48 89 c8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85
RIP: copy_func_state kernel/bpf/verifier.c:403 [inline] RSP:  
ffff8801c7fff130
RIP: copy_verifier_state+0x364/0x590 kernel/bpf/verifier.c:431 RSP:  
ffff8801c7fff130
---[ end trace 18f3ab976ca58c6c ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
    (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..

---
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