syzbot


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

Status: fixed on 2018/08/07 13:43
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+7700e2bdb39076b6645d@syzkaller.appspotmail.com
Fix commit: 99ba2b5aba24 bpf: sockhash, disallow bpf_tcp_close and update in parallel
First crash: 2161d, last: 2161d

Sample crash report:
==================================================================
BUG: KASAN: stack-out-of-bounds in enqueue_task_fair+0x3ab/0x910 kernel/sched/fair.c:5424
Read of size 8 at addr ffff8801aa1fa918 by task blkid/9200
PANIC: double fault, error_code: 0x0

CPU: 0 PID: 9192 Comm: syz-executor3 Not tainted 4.18.0-rc3+ #57
CPU: 1 PID: 9200 Comm: blkid Not tainted 4.18.0-rc3+ #57
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__lock_acquire+0x2e/0x5020 kernel/locking/lockdep.c:3294
Call Trace:
Code: 41 
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
57 41 
89 
cf 
41 
56 41 
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
55 
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
49 89 
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
fd 
 enqueue_task_fair+0x3ab/0x910 kernel/sched/fair.c:5424
41 
54 
45 89 
cc 53 
 enqueue_task kernel/sched/core.c:751 [inline]
 activate_task+0x123/0x2e0 kernel/sched/core.c:770
65 
 ttwu_activate kernel/sched/core.c:1659 [inline]
 ttwu_do_activate+0xd5/0x1f0 kernel/sched/core.c:1718
4c 8b 
 ttwu_queue kernel/sched/core.c:1863 [inline]
 try_to_wake_up+0x948/0x12b0 kernel/sched/core.c:2076
34 
25 40 
ee 01 
00 
48 83 
e4 
f0 
48 81 
ec 
60 
03 
00 
00 48 
 wake_up_process+0x10/0x20 kernel/sched/core.c:2149
8b 45 
 hrtimer_wakeup+0x48/0x60 kernel/time/hrtimer.c:1647
10 <89> 
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x3eb/0x10c0 kernel/time/hrtimer.c:1460
94 
24 
80 00 
00 00 
48 ba 
00 00 
00 
00 00 
fc 
ff df 
48 
89 
 hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518
84 24 
 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
98 
RSP: 0018:ffff8801a8b54f60 EFLAGS: 00010086
RAX: 0000000000000000 RBX: 1ffff1003516aa68 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff88f92620
RBP: ffff8801a8b552e8 R08: 0000000000000000 R09: 0000000000000000
R10: ffff8801aa57fbe0 R11: ffff8801d904acfb R12: 0000000000000000
R13: ffffffff88f92620 R14: ffff8801d904a580 R15: 0000000000000002
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
FS:  0000000001156940(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
 </IRQ>
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff8801a8b54f58 CR3: 00000001d699d000 CR4: 00000000001406f0
RIP: 0033:0x7fa7a88df79d
DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000020000000
Code: 
DR3: 0000000020000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
85 

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/07/18 03:38 bpf-next dc989d2ce2c2 6d5bd5b5 .config console log report ci-upstream-bpf-next-kasan-gce
* Struck through repros no longer work on HEAD.