syzbot


BUG: unable to handle kernel paging request in update_rq_clock

Status: upstream: reported on 2025/07/01 01:53
Reported-by: syzbot+d59af6aff2b50d7575c5@syzkaller.appspotmail.com
First crash: 25d, last: 25d
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-use-after-free Read in update_rq_clock kernel 19 1 338d 334d 0/29 auto-obsoleted due to no activity on 2024/10/21 09:09

Sample crash report:
BUG: unable to handle page fault for address: ffffff88802b1c49
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD c691067 P4D c691067 PUD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 6.1.142-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:is_idle_task include/linux/sched.h:1922 [inline]
RIP: 0010:update_rq_clock_pelt kernel/sched/pelt.h:97 [inline]
RIP: 0010:update_rq_clock_task kernel/sched/core.c:726 [inline]
RIP: 0010:update_rq_clock+0x25d/0x440 kernel/sched/core.c:748
Code: 42 80 3c 28 00 74 08 4c 89 ff e8 2e 95 7a 00 4d 8b 3f 49 83 c7 2c 4c 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 85 01 00 00 <41> f6 07 02 0f 85 af 00 00 00 48 8b 44 24 08 42 0f b6 04 28 84 c0
RSP: 0000:ffffc90000007e68 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffff8880b8f3aa80 RCX: 9b0596fe66d25000
RDX: 1ffffffff1ef9c00 RSI: ffffffff8f7ce01c RDI: ffffffff8f7ce000
RBP: 00000000000056d0 R08: ffffffff8f7ce008 R09: ffffffff8f7ce018
R10: ffffffff8f7ce010 R11: ffffffff8f7ce003 R12: ffff8880b8f3b500
R13: dffffc0000000000 R14: 00000000ac05cfd9 R15: ffffff88802b1c49
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffff88802b1c49 CR3: 000000005305f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 ttwu_runnable kernel/sched/core.c:3737 [inline]
 try_to_wake_up+0x11a/0x1080 kernel/sched/core.c:4141
 swake_up_locked kernel/sched/swait.c:29 [inline]
 complete+0x9e/0x1b0 kernel/sched/completion.c:36
 __flush_smp_call_function_queue+0x60f/0xd20 kernel/smp.c:676
 __sysvec_call_function_single+0xba/0x350 arch/x86/kernel/smp.c:267
 instr_sysvec_call_function_single arch/x86/kernel/smp.c:262 [inline]
 sysvec_call_function_single+0x98/0xc0 arch/x86/kernel/smp.c:262
 </IRQ>
 <TASK>
 asm_sysvec_call_function_single+0x16/0x20 arch/x86/include/asm/idtentry.h:699
RIP: 0010:blk_account_io_done+0x4cb/0x5f0 block/blk-mq.c:994
Code: f7 e8 99 86 e3 fd 49 8b 06 48 8d 9c 18 88 00 00 00 43 0f b6 44 3d 00 84 c0 0f 85 12 01 00 00 41 8b 04 24 83 e0 01 48 ff 0c c3 <bf> 01 00 00 00 e8 ab e1 68 fd 65 8b 1d 7c a2 13 7c 31 ff 89 de e8
RSP: 0000:ffffc90000147bd8 EFLAGS: 00000206
RAX: 0000000000000000 RBX: ffffe8ffffc0f298 RCX: ffff88813feb3b80
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000008
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1bfd1a6
R10: fffffbfff1bfd1a6 R11: 1ffffffff1bfd1a5 R12: ffff888024762858
R13: 1ffff110048ec50b R14: ffffffff8c3d1970 R15: dffffc0000000000
 __blk_mq_end_request_acct block/blk-mq.c:1028 [inline]
 __blk_mq_end_request+0x2b7/0x550 block/blk-mq.c:1034
 blk_complete_reqs block/blk-mq.c:1130 [inline]
 blk_done_softirq+0x100/0x150 block/blk-mq.c:1135
 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
 run_ksoftirqd+0x98/0xf0 kernel/softirq.c:963
 smpboot_thread_fn+0x64a/0xa40 kernel/smpboot.c:164
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Modules linked in:
CR2: ffffff88802b1c49
---[ end trace 0000000000000000 ]---
RIP: 0010:is_idle_task include/linux/sched.h:1922 [inline]
RIP: 0010:update_rq_clock_pelt kernel/sched/pelt.h:97 [inline]
RIP: 0010:update_rq_clock_task kernel/sched/core.c:726 [inline]
RIP: 0010:update_rq_clock+0x25d/0x440 kernel/sched/core.c:748
Code: 42 80 3c 28 00 74 08 4c 89 ff e8 2e 95 7a 00 4d 8b 3f 49 83 c7 2c 4c 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 85 01 00 00 <41> f6 07 02 0f 85 af 00 00 00 48 8b 44 24 08 42 0f b6 04 28 84 c0
RSP: 0000:ffffc90000007e68 EFLAGS: 00010046

RAX: 0000000000000000 RBX: ffff8880b8f3aa80 RCX: 9b0596fe66d25000
RDX: 1ffffffff1ef9c00 RSI: ffffffff8f7ce01c RDI: ffffffff8f7ce000
RBP: 00000000000056d0 R08: ffffffff8f7ce008 R09: ffffffff8f7ce018
R10: ffffffff8f7ce010 R11: ffffffff8f7ce003 R12: ffff8880b8f3b500
R13: dffffc0000000000 R14: 00000000ac05cfd9 R15: ffffff88802b1c49
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffff88802b1c49 CR3: 000000005305f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1)
   5:	74 08                	je     0xf
   7:	4c 89 ff             	mov    %r15,%rdi
   a:	e8 2e 95 7a 00       	call   0x7a953d
   f:	4d 8b 3f             	mov    (%r15),%r15
  12:	49 83 c7 2c          	add    $0x2c,%r15
  16:	4c 89 f8             	mov    %r15,%rax
  19:	48 c1 e8 03          	shr    $0x3,%rax
  1d:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax
  22:	84 c0                	test   %al,%al
  24:	0f 85 85 01 00 00    	jne    0x1af
* 2a:	41 f6 07 02          	testb  $0x2,(%r15) <-- trapping instruction
  2e:	0f 85 af 00 00 00    	jne    0xe3
  34:	48 8b 44 24 08       	mov    0x8(%rsp),%rax
  39:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax
  3e:	84 c0                	test   %al,%al

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/01 12:18 linux-6.1.y 7e69c33e4858 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan BUG: unable to handle kernel paging request in update_rq_clock
2025/07/01 01:52 linux-6.1.y 7e69c33e4858 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan BUG: unable to handle kernel paging request in update_rq_clock
* Struck through repros no longer work on HEAD.