syzbot


BUG: unable to handle kernel paging request in process_srcu

Status: moderation: reported on 2025/03/11 10:55
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+f994f893ad3476b150ec@syzkaller.appspotmail.com
First crash: 4d18h, last: 4d18h
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: uninit-value in process_srcu block 3 700d 743d 0/28 auto-obsoleted due to no activity on 2023/07/10 12:54
upstream KASAN: slab-use-after-free Read in process_srcu kernel 3 283d 296d 0/28 auto-obsoleted due to no activity on 2024/08/30 14:51

Sample crash report:
BUG: unable to handle page fault for address: ffffffff919c1b50
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD e93c067 P4D e93c067 PUD e93d063 PMD 35620063 PTE 800fffffee63e062
Oops: Oops: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 9 Comm: kworker/0:1 Not tainted 6.14.0-rc5-syzkaller-00109-g0f52fd4f67c6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: rcu_gp process_srcu
RIP: 0010:__queue_work+0x5a6/0x1090 kernel/workqueue.c:2271
Code: 89 ef e8 7d 6f 9d 00 48 03 5d 00 48 89 d8 48 c1 e8 03 48 bd 00 00 00 00 00 fc ff df 80 3c 28 00 74 08 48 89 df e8 5a 6f 9d 00 <4c> 8b 2b e8 b2 b1 77 0a 89 c3 31 ff 89 c6 e8 47 bf 38 00 85 db 74
RSP: 0018:ffffc900000e7888 EFLAGS: 00010046
RAX: 1ffffffff233836a RBX: ffffffff919c1b50 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000008
RBP: dffffc0000000000 R08: ffffffff818912db R09: 1ffffffff28a2908
R10: dffffc0000000000 R11: fffffbfff28a2909 R12: 1ffff110036105b8
R13: ffff88801b082c00 R14: 0000000000000002 R15: ffffe8ffffc7c7a0
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff919c1b50 CR3: 000000005f0ce000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 queue_work_on+0x1c2/0x380 kernel/workqueue.c:2392
 srcu_queue_delayed_work_on kernel/rcu/srcutree.c:831 [inline]
 srcu_schedule_cbs_sdp kernel/rcu/srcutree.c:844 [inline]
 srcu_gp_end kernel/rcu/srcutree.c:911 [inline]
 srcu_advance_state kernel/rcu/srcutree.c:1747 [inline]
 process_srcu+0xf0d/0x12e0 kernel/rcu/srcutree.c:1851
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Modules linked in:
CR2: ffffffff919c1b50
---[ end trace 0000000000000000 ]---
RIP: 0010:__queue_work+0x5a6/0x1090 kernel/workqueue.c:2271
Code: 89 ef e8 7d 6f 9d 00 48 03 5d 00 48 89 d8 48 c1 e8 03 48 bd 00 00 00 00 00 fc ff df 80 3c 28 00 74 08 48 89 df e8 5a 6f 9d 00 <4c> 8b 2b e8 b2 b1 77 0a 89 c3 31 ff 89 c6 e8 47 bf 38 00 85 db 74
RSP: 0018:ffffc900000e7888 EFLAGS: 00010046
RAX: 1ffffffff233836a RBX: ffffffff919c1b50 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000008
RBP: dffffc0000000000 R08: ffffffff818912db R09: 1ffffffff28a2908
R10: dffffc0000000000 R11: fffffbfff28a2909 R12: 1ffff110036105b8
R13: ffff88801b082c00 R14: 0000000000000002 R15: ffffe8ffffc7c7a0
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff919c1b50 CR3: 000000005f0ce000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	89 ef                	mov    %ebp,%edi
   2:	e8 7d 6f 9d 00       	call   0x9d6f84
   7:	48 03 5d 00          	add    0x0(%rbp),%rbx
   b:	48 89 d8             	mov    %rbx,%rax
   e:	48 c1 e8 03          	shr    $0x3,%rax
  12:	48 bd 00 00 00 00 00 	movabs $0xdffffc0000000000,%rbp
  19:	fc ff df
  1c:	80 3c 28 00          	cmpb   $0x0,(%rax,%rbp,1)
  20:	74 08                	je     0x2a
  22:	48 89 df             	mov    %rbx,%rdi
  25:	e8 5a 6f 9d 00       	call   0x9d6f84
* 2a:	4c 8b 2b             	mov    (%rbx),%r13 <-- trapping instruction
  2d:	e8 b2 b1 77 0a       	call   0xa77b1e4
  32:	89 c3                	mov    %eax,%ebx
  34:	31 ff                	xor    %edi,%edi
  36:	89 c6                	mov    %eax,%esi
  38:	e8 47 bf 38 00       	call   0x38bf84
  3d:	85 db                	test   %ebx,%ebx
  3f:	74                   	.byte 0x74

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/07 10:51 upstream 0f52fd4f67c6 831e3629 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs BUG: unable to handle kernel paging request in process_srcu
* Struck through repros no longer work on HEAD.