Subject: WARNING in bpf_prog_kallsyms_add

From: syzbot <[email-masked]>
Date: Fri, 04 Jan 2019 07:41:04 -0800

Hello,

syzbot found the following crash on:

HEAD commit:    645ff1e8e704 Merge branch 'for-linus' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14a5c64b400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=20271e14bc1c87f0
dashboard link: https://syzkaller.appspot.com/bug?extid=987e48d84abddbe2506d
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=13c69d20c00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: [email-masked]

8021q: adding VLAN 0 to HW filter on device batadv0
8021q: adding VLAN 0 to HW filter on device batadv0
IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready
8021q: adding VLAN 0 to HW filter on device batadv0
8021q: adding VLAN 0 to HW filter on device batadv0
WARNING: CPU: 1 PID: 8154 at kernel/bpf/core.c:578 bpf_prog_ksym_node_add  
kernel/bpf/core.c:578 [inline]
WARNING: CPU: 1 PID: 8154 at kernel/bpf/core.c:578  
bpf_prog_kallsyms_add+0x909/0xaf0 kernel/bpf/core.c:610
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 8154 Comm: syz-executor0 Not tainted 4.20.0+ #7
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+0x1db/0x2d0 lib/dump_stack.c:113
  panic+0x2cb/0x589 kernel/panic.c:189
  __warn.cold+0x20/0x4b kernel/panic.c:544
  report_bug+0x263/0x2b0 lib/bug.c:186
  fixup_bug arch/x86/kernel/traps.c:178 [inline]
  fixup_bug arch/x86/kernel/traps.c:173 [inline]
  do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271
  do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:290
  invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
RIP: 0010:bpf_prog_ksym_node_add kernel/bpf/core.c:578 [inline]
RIP: 0010:bpf_prog_kallsyms_add+0x909/0xaf0 kernel/bpf/core.c:610
Code: 2d d9 36 00 e9 a4 fe ff ff 31 db 48 c7 c0 f0 db 80 89 e9 a0 fb ff ff  
31 db 48 c7 c0 e8 db 80 89 e9 f6 fc ff ff e8 37 06 f3 ff <0f> 0b e9 c6 f8  
ff ff 48 89 85 10 ff ff ff e8 54 d9 36 00 48 8b 85
RSP: 0018:ffff88808de979b8 EFLAGS: 00010293
RAX: ffff8880901a6280 RBX: ffff88809292c628 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff818e9039 RDI: ffffc90001933020
RBP: ffff88808de97ac8 R08: 1ffff11011bd2f24 R09: ffffed1011bd2f25
R10: ffffed1011bd2f24 R11: 0000000000000003 R12: ffff88809292c5c0
R13: 1ffff11011bd2f48 R14: ffff88808de97aa0 R15: ffffffff899f1c80
  bpf_prog_load+0x13a9/0x1d00 kernel/bpf/syscall.c:1556
  __do_sys_bpf+0xc52/0x4410 kernel/bpf/syscall.c:2618
  __se_sys_bpf kernel/bpf/syscall.c:2580 [inline]
  __x64_sys_bpf+0x73/0xb0 kernel/bpf/syscall.c:2580
  do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457ec9
Code: 6d 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 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f94ae545c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9
RDX: 0000000000000048 RSI: 0000000020000780 RDI: 0000000000000005
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f94ae5466d4
R13: 00000000004be236 R14: 00000000004ce360 R15: 00000000ffffffff
Kernel Offset: disabled
Rebooting in 86400 seconds..

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