syzbot


BUG: unable to handle kernel paging request in find_lock_lowest_rq

Status: moderation: reported on 2024/06/10 00:55
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+a31ed07855a48cbcb76d@syzkaller.appspotmail.com
First crash: 20d, last: 20d

Sample crash report:
BUG: unable to handle page fault for address: fffffbfff2b36b63
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 23ffe4067 P4D 23ffe4067 PUD 23ffe3067 PMD 0 
Oops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 PID: 8452 Comm: syz-executor.5 Not tainted 6.10.0-rc2-syzkaller-00064-g71d7b52cc33b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:87 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:104 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x82/0x290 mm/kasan/generic.c:189
Code: 01 00 00 00 00 fc ff df 4f 8d 3c 31 4c 89 fd 4c 29 dd 48 83 fd 10 7f 29 48 85 ed 0f 84 3e 01 00 00 4c 89 cd 48 f7 d5 48 01 dd <41> 80 3b 00 0f 85 c9 01 00 00 49 ff c3 48 ff c5 75 ee e9 1e 01 00
RSP: 0018:ffffc9000484f5e0 EFLAGS: 00010086
RAX: 0000000000541a01 RBX: 1ffffffff2b36b63 RCX: ffffffff8172778d
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff959b5b18
RBP: ffffffffffffffff R08: ffffffff959b5b1f R09: 1ffffffff2b36b63
R10: dffffc0000000000 R11: fffffbfff2b36b63 R12: 0000000000000001
R13: ffff888020bc5a00 R14: dffffc0000000001 R15: fffffbfff2b36b64
FS:  0000555568719480(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffbfff2b36b63 CR3: 000000007cc5e000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 __lock_acquire+0xc5d/0x1fd0 kernel/locking/lockdep.c:5107
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
 _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378
 raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559
 _double_lock_balance kernel/sched/sched.h:2715 [inline]
 double_lock_balance kernel/sched/sched.h:2760 [inline]
 find_lock_lowest_rq+0x1e1/0x670 kernel/sched/rt.c:1941
 push_rt_task+0x13f/0x7e0 kernel/sched/rt.c:2074
 push_rt_tasks kernel/sched/rt.c:2124 [inline]
 task_woken_rt+0x14c/0x220 kernel/sched/rt.c:2424
 ttwu_do_activate+0x338/0x7e0 kernel/sched/core.c:3805
 ttwu_queue kernel/sched/core.c:4057 [inline]
 try_to_wake_up+0x884/0x1470 kernel/sched/core.c:4378
 signal_wake_up_state+0xb4/0x120 kernel/signal.c:773
 signal_wake_up include/linux/sched/signal.h:448 [inline]
 complete_signal+0xb36/0xcf0 kernel/signal.c:1055
 __send_signal_locked+0xb1b/0xdc0 kernel/signal.c:1185
 do_send_sig_info kernel/signal.c:1301 [inline]
 group_send_sig_info+0x292/0x310 kernel/signal.c:1451
 __kill_pgrp_info kernel/signal.c:1467 [inline]
 kill_something_info kernel/signal.c:1617 [inline]
 __do_sys_kill kernel/signal.c:3830 [inline]
 __se_sys_kill+0x431/0x5d0 kernel/signal.c:3824
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff3068405c7
Code: 48 83 c4 08 c3 66 0f 1f 44 00 00 48 c7 c2 b0 ff ff ff 64 89 02 b8 ff ff ff ff eb e4 0f 1f 80 00 00 00 00 b8 3e 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe5dcdc558 EFLAGS: 00000293 ORIG_RAX: 000000000000003e
RAX: ffffffffffffffda RBX: 00000000000004db RCX: 00007ff3068405c7
RDX: 0000000000000591 RSI: 0000000000000009 RDI: 00000000fffffb25
RBP: 00007ffe5dcdc5ac R08: 0000000006bf36b6 R09: 7fffffffffffffff
R10: 00007ff3076590b8 R11: 0000000000000293 R12: 0000000000000064
R13: 00000000001265b8 R14: 0000000000125ea5 R15: 0000000000000015
 </TASK>
Modules linked in:
CR2: fffffbfff2b36b63
---[ end trace 0000000000000000 ]---
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:87 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:104 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x82/0x290 mm/kasan/generic.c:189
Code: 01 00 00 00 00 fc ff df 4f 8d 3c 31 4c 89 fd 4c 29 dd 48 83 fd 10 7f 29 48 85 ed 0f 84 3e 01 00 00 4c 89 cd 48 f7 d5 48 01 dd <41> 80 3b 00 0f 85 c9 01 00 00 49 ff c3 48 ff c5 75 ee e9 1e 01 00
RSP: 0018:ffffc9000484f5e0 EFLAGS: 00010086
RAX: 0000000000541a01 RBX: 1ffffffff2b36b63 RCX: ffffffff8172778d
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff959b5b18
RBP: ffffffffffffffff R08: ffffffff959b5b1f R09: 1ffffffff2b36b63
R10: dffffc0000000000 R11: fffffbfff2b36b63 R12: 0000000000000001
R13: ffff888020bc5a00 R14: dffffc0000000001 R15: fffffbfff2b36b64
FS:  0000555568719480(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffbfff2b36b63 CR3: 000000007cc5e000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 7 bytes skipped:
   0:	df 4f 8d             	fisttps -0x73(%rdi)
   3:	3c 31                	cmp    $0x31,%al
   5:	4c 89 fd             	mov    %r15,%rbp
   8:	4c 29 dd             	sub    %r11,%rbp
   b:	48 83 fd 10          	cmp    $0x10,%rbp
   f:	7f 29                	jg     0x3a
  11:	48 85 ed             	test   %rbp,%rbp
  14:	0f 84 3e 01 00 00    	je     0x158
  1a:	4c 89 cd             	mov    %r9,%rbp
  1d:	48 f7 d5             	not    %rbp
  20:	48 01 dd             	add    %rbx,%rbp
* 23:	41 80 3b 00          	cmpb   $0x0,(%r11) <-- trapping instruction
  27:	0f 85 c9 01 00 00    	jne    0x1f6
  2d:	49 ff c3             	inc    %r11
  30:	48 ff c5             	inc    %rbp
  33:	75 ee                	jne    0x23
  35:	e9                   	.byte 0xe9
  36:	1e                   	(bad)
  37:	01 00                	add    %eax,(%rax)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/06 00:45 upstream 71d7b52cc33b 121701b6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root BUG: unable to handle kernel paging request in find_lock_lowest_rq
* Struck through repros no longer work on HEAD.