syzbot


WARNING in bpf_prog_kallsyms_add

Status: fixed on 2019/09/06 20:45
Subsystems: bpf
[Documentation on labels]
Reported-by: syzbot+987e48d84abddbe2506d@syzkaller.appspotmail.com
Fix commit: c751798aa224 bpf: fix use after free in prog symbol exposure
First crash: 1967d, last: 1763d
Cause bisection: introduced by (bisect log) :
commit 7607dd35fc34893214284cca740d015154d20452
Author: Ido Schimmel <idosch@mellanox.com>
Date: Mon Jul 17 12:15:30 2017 +0000

  mlxsw: spectrum: Trap IPv4 packets with Router Alert option

Crash: WARNING: refcount bug in addrconf_del_dad_work (log)
Repro: syz .config
  
Fix bisection: fixed by (bisect log) :
commit 06ee7115b0d1742de745ad143fb5e06d77d27fba
Author: Alexei Starovoitov <ast@kernel.org>
Date: Tue Apr 2 04:27:40 2019 +0000

  bpf: add verifier stats and log_level bit 2

  
Discussions (3)
Title Replies (including bot) Last reply
Reminder: 36 open syzbot bugs in "net/bpf" subsystem 1 (1) 2019/07/03 06:01
Reminder: 30 open syzbot bugs in "net/bpf" subsystem 1 (1) 2019/06/24 05:01
WARNING in bpf_prog_kallsyms_add 2 (4) 2019/03/26 08:27
Last patch testing requests (1)
Created Duration User Patch Repo Result
2019/08/26 08:08 17m daniel@iogearbox.net bpf OK

Sample crash report:
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..

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/01/03 22:01 upstream 645ff1e8e704 66fcd29b .config console log report syz ci-upstream-kasan-gce-root
2019/07/26 08:50 bpf-next 192f0f8e9db7 732bc5a0 .config console log report ci-upstream-bpf-next-kasan-gce
* Struck through repros no longer work on HEAD.