syzbot


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

Status: fixed on 2018/08/07 13:43
Subsystems: kernel
[Documentation on labels]
Fix commit: 99ba2b5aba24 bpf: sockhash, disallow bpf_tcp_close and update in parallel
First crash: 2167d, last: 2167d

Sample crash report:
==================================================================
BUG: KASAN: stack-out-of-bounds in __enqueue_entity+0x133/0x1f0 kernel/sched/fair.c:545
Read of size 8 at addr ffff8801b42f92a0 by task udevd/20299

kasan: CONFIG_KASAN_INLINE enabled
CPU: 0 PID: 20299 Comm: udevd Not tainted 4.18.0-rc3+ #53
kasan: GPF could be caused by NULL-ptr deref or user memory access
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
general protection fault: 0000 [#1] SMP KASAN
Call Trace:
CPU: 1 PID: -2000753008 Comm:  Not tainted 4.18.0-rc3+ #53
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:update_curr+0xa2/0xc00 kernel/sched/fair.c:806
Code: 
40 14 
00 f2 
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
f2 
f2 
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
c7 
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
40 
 __enqueue_entity+0x133/0x1f0 kernel/sched/fair.c:545
18 
 put_prev_entity+0xbf/0x2a0 kernel/sched/fair.c:4486
f2 
 put_prev_task_fair+0x3e/0x80 kernel/sched/fair.c:7044
f2 
 put_prev_task kernel/sched/sched.h:1535 [inline]
 pick_next_task_stop+0xc0/0x1f0 kernel/sched/stop_task.c:34
f2 
 pick_next_task kernel/sched/core.c:3363 [inline]
 __schedule+0x1401/0x1ed0 kernel/sched/core.c:3478
f2 
c7 
40 
1c 
00 
f2 
f2 
f2 
65 
 preempt_schedule_common+0x22/0x60 kernel/sched/core.c:3628
48 
 _cond_resched+0x1d/0x30 kernel/sched/core.c:4994
8b 
 stop_one_cpu+0x173/0x240 kernel/stop_machine.c:133
04 
25 28 
00 00 
00 
48 
89 
 sched_exec+0x1bf/0x2a0 kernel/sched/core.c:2995
45 
d0 
31 
 __do_execve_file.isra.36+0xb50/0x2730 fs/exec.c:1760
c0 
48 
89 
f8 
48 
c1 e8 
03 
<80> 
3c 
10 
00 
0f 
85 0f 
09 
00 00 
49 
 do_execveat_common fs/exec.c:1866 [inline]
 do_execve fs/exec.c:1883 [inline]
 __do_sys_execve fs/exec.c:1964 [inline]
 __se_sys_execve fs/exec.c:1959 [inline]
 __x64_sys_execve+0x8f/0xc0 fs/exec.c:1959
8d 
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
bf 
70 
01 00 
00 
49 
8b 
5f 
40 
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
48 
RIP: 0033:0x7f908868c207
Code: 
RSP: 0018:ffff8801daf07828 EFLAGS: 00010002
77 
19 
RAX: 0000000000000008 RBX: dffffc0000000000 RCX: 1ffffffff0fd511b
f4 
RDX: dffffc0000000000 RSI: ffff8801b20b6640 RDI: 0000000000000040
48 
RBP: ffff8801daf07990 R08: ffff88021fff8058 R09: ffff88021fff805b
89 
R10: ffffed0043fff009 R11: 0000000000000000 R12: 1ffff1003b5e0f09
d7 
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
44 
FS:  00000000017b4940(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
89 c0 
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
0f 05 
CR2: 00007f17d1827848 CR3: 0000000199451000 CR4: 00000000001406e0
48 
DR0: 00000000200001c0 DR1: 0000000020000080 DR2: 0000000000000000
3d 
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
00 
Call Trace:
f0 ff 
 <IRQ>
ff 
76 
e0 
f7 
d8 
64 
 entity_tick kernel/sched/fair.c:4499 [inline]
 task_tick_fair+0xdb/0x320 kernel/sched/fair.c:9934
41 
 scheduler_tick+0x18b/0x430 kernel/sched/core.c:3087
89 
01 
eb 
d8 
f7 
d8 
64 
 update_process_times+0x51/0x70 kernel/time/timer.c:1641
41 
 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164
89 
 tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274
01 
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x3eb/0x10c0 kernel/time/hrtimer.c:1460
eb 
df 
b8 
3b 
00 
00 
00 
0f 
05 
<48> 
3d 
00 
 hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518
f0 ff 
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline]
 smp_apic_timer_interrupt+0x165/0x730 arch/x86/kernel/apic/apic.c:1050
ff 
77 
02 
f3 
c3 
48 
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
8b 
 </IRQ>
15 
Modules linked in:
00 
8c 
Dumping ftrace buffer:
2d 
   (ftrace buffer empty)
00 f7 
---[ end trace 477eb5a7e89bc623 ]---
d8 
RIP: 0010:update_curr+0xa2/0xc00 kernel/sched/fair.c:806
64 
Code: 
89 
40 
02 
14 
00 f2 
RSP: 002b:00007ffcc4d0d7d8 EFLAGS: 00000206
f2 f2 
 ORIG_RAX: 000000000000003b
c7 
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f908868c207
40 
RDX: 00000000010b7540 RSI: 00007ffcc4d0d8d0 RDI: 00007ffcc4d0e8e0
18 
RBP: 0000000000625500 R08: 0000000000000ac4 R09: 0000000000000ac4
f2 f2 f2 
R10: 0000000000000000 R11: 0000000000000206 R12: 00000000010b7540
f2 
R13: 0000000000000007 R14: 00000000010a6250 R15: 0000000000000005
c7 

40 1c 
Allocated by task 0:
00 
(stack is not available)
f2 

f2 
Freed by task 5412:
f2 
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
65 
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
48 
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
8b 
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xd9/0x260 mm/slab.c:3813
04 
 skb_free_head+0x99/0xc0 net/core/skbuff.c:550
25 28 
 skb_release_data+0x6a4/0x880 net/core/skbuff.c:570
00 
 skb_release_all+0x4a/0x60 net/core/skbuff.c:627
00 
 __kfree_skb net/core/skbuff.c:641 [inline]
 consume_skb+0x193/0x560 net/core/skbuff.c:701
00 
 netlink_broadcast_filtered+0x6aa/0x1620 net/netlink/af_netlink.c:1512
48 
 netlink_broadcast net/netlink/af_netlink.c:1534 [inline]
 nlmsg_multicast include/net/netlink.h:591 [inline]
 nlmsg_notify+0xa0/0x1a0 net/netlink/af_netlink.c:2491
89 
 rtnl_notify+0xce/0xf0 net/core/rtnetlink.c:732
45 
 rtmsg_fib+0x369/0x4d0 net/ipv4/fib_semantics.c:428
d0 
 fib_table_insert+0x7a8/0x17a0 net/ipv4/fib_trie.c:1287
31 c0 
 fib_magic.isra.22+0x66b/0x890 net/ipv4/fib_frontend.c:885
48 
 fib_add_ifaddr+0x382/0x500 net/ipv4/fib_frontend.c:920
89 
 fib_netdev_event+0x13c/0x3a0 net/ipv4/fib_frontend.c:1263
f8 48 
 notifier_call_chain+0x180/0x390 kernel/notifier.c:93
c1 
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
e8 
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1734
03 
 call_netdevice_notifiers net/core/dev.c:1752 [inline]
 __dev_notify_flags+0x17a/0x480 net/core/dev.c:7335
<80> 
 dev_change_flags+0xfd/0x150 net/core/dev.c:7371
3c 
 do_setlink+0xb16/0x3dd0 net/core/rtnetlink.c:2413
10 
 rtnl_newlink+0x138d/0x1d60 net/core/rtnetlink.c:3023
00 0f 
 rtnetlink_rcv_msg+0x46e/0xc30 net/core/rtnetlink.c:4699
85 
 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2448
0f 
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4717
09 
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x5a0/0x760 net/netlink/af_netlink.c:1336
00 
 netlink_sendmsg+0xa18/0xfc0 net/netlink/af_netlink.c:1901
00 
 sock_sendmsg_nosec net/socket.c:641 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:651
49 
 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2125
8d 
 __sys_sendmsg+0x11d/0x290 net/socket.c:2163
bf 70 
 __do_sys_sendmsg net/socket.c:2172 [inline]
 __se_sys_sendmsg net/socket.c:2170 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2170
01 
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
00 
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
00 

49 
The buggy address belongs to the object at ffff8801b42f9280
 which belongs to the cache kmalloc-512 of size 512
8b 
The buggy address is located 32 bytes inside of
 512-byte region [ffff8801b42f9280, ffff8801b42f9480)
5f 
The buggy address belongs to the page:
40 
page:ffffea0006d0be40 count:1 mapcount:0 mapping:ffff8801da800940 index:0xffff8801b42f9c80
48 
RSP: 0018:ffff8801daf07828 EFLAGS: 00010002
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffffea0006b45c88 ffffea0006ad5408 ffff8801da800940
raw: ffff8801b42f9c80 ffff8801b42f9000 0000000100000004 0000000000000000
RAX: 0000000000000008 RBX: dffffc0000000000 RCX: 1ffffffff0fd511b
page dumped because: kasan: bad access detected
RDX: dffffc0000000000 RSI: ffff8801b20b6640 RDI: 0000000000000040

RBP: ffff8801daf07990 R08: ffff88021fff8058 R09: ffff88021fff805b
Memory state around the buggy address:
R10: ffffed0043fff009 R11: 0000000000000000 R12: 1ffff1003b5e0f09
 ffff8801b42f9180: f1 f1 f1 00 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2 f2
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 ffff8801b42f9200: f2 f2 f2 00 f2 f2 f2 f2 f2 f2 f2 f8 f2 f2 f2 f2
FS:  00000000017b4940(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
>ffff8801b42f9280: f2 f2 f2 00 f2 f2 f2 00 00 00 00 00 00 00 00 00
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
                               ^
CR2: 00007f17d1827848 CR3: 0000000199451000 CR4: 00000000001406e0
 ffff8801b42f9300: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
DR0: 00000000200001c0 DR1: 0000000020000080 DR2: 0000000000000000
 ffff8801b42f9380: 00 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2 f2 f2 f2 f2
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/07/14 16:10 bpf-next d23b27c02f03 92a49505 .config console log report ci-upstream-bpf-next-kasan-gce
* Struck through repros no longer work on HEAD.