syzbot


KASAN: stack-out-of-bounds Read in neigh_flush_dev

Status: fixed on 2018/08/07 13:43
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+1dce5f906943dfcdfe59@syzkaller.appspotmail.com
Fix commit: 99ba2b5aba24 bpf: sockhash, disallow bpf_tcp_close and update in parallel
First crash: 2106d, last: 2106d

Sample crash report:
netlink: 8 bytes leftover after parsing attributes in process `syz-executor6'.
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
==================================================================
BUG: KASAN: stack-out-of-bounds in neigh_flush_dev+0x82f/0x900 net/core/neighbour.c:249
Read of size 8 at addr ffff880190b382c0 by task syz-executor0/14089

CPU: 1 PID: 14089 Comm: syz-executor0 Not tainted 4.18.0-rc4+ #144
PANIC: double fault, error_code: 0x0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
CPU: 0 PID: 14090 Comm: syz-executor5 Not tainted 4.18.0-rc4+ #144
Call Trace:
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mark_lock+0x46/0x19f0 kernel/locking/lockdep.c:3118
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
Code: 00 
00 00 
41 56 
41 d3 
e7 41 
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
55 4c 
8d 6e 
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
20 41 
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
54 49 
 neigh_flush_dev+0x82f/0x900 net/core/neighbour.c:249
89 f4 
53 48 
8d 9d 
f8 fe 
ff ff 
48 c1 
eb 03 
48 8d 04 13 
 neigh_changeaddr+0x2f/0x40 net/core/neighbour.c:288
48 81 
 ndisc_netdev_event+0x509/0x580 net/ipv6/ndisc.c:1786
ec 08 
01 00 
00 <48> 
c7 85 
 notifier_call_chain+0x180/0x390 kernel/notifier.c:93
f8 fe 
ff ff 
b3 8a 
b5 41 
48 c7 
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
85 00 
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1735
ff ff 
 __dev_notify_flags+0x3dc/0x480 net/core/dev.c:7043
ff 80 
77 bd 
88 
RSP: 0018:ffff88018edfffc0 EFLAGS: 00010086
RAX: ffffed0031dbfffd RBX: 1ffff10031dbfffd RCX: 0000000000000008
RDX: dffffc0000000000 RSI: ffff8801b0e38f20 RDI: ffff8801b0e386c0
RBP: ffff88018ee000f0 R08: 0000000000000008 R09: 0000000000000001
R10: ffff8801b0e386c0 R11: ffff8801b0e38ee4 R12: ffff8801b0e38f20
 dev_change_flags+0xfd/0x150 net/core/dev.c:7065
R13: ffff8801b0e38f40 R14: ffff8801b0e386c0 R15: 0000000000000100
FS:  00000000015c8940(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
 do_setlink+0xb1d/0x3e10 net/core/rtnetlink.c:2376
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff88018edfffb8 CR3: 00000001d92d0000 CR4: 00000000001406f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/07/13 15:16 upstream 63f047771621 92a49505 .config console log report ci-upstream-kasan-gce-root
* Struck through repros no longer work on HEAD.