syzbot


general protection fault in cgroup_rstat_flush

Status: moderation: reported on 2025/04/02 18:32
Subsystems: cgroups
[Documentation on labels]
Reported-by: syzbot+6c21f0fc03dec816dc2b@syzkaller.appspotmail.com
First crash: 25d, last: 3d13h

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xe7ffed1c347cf773: 0000 [#1] SMP KASAN PTI
KASAN: maybe wild-memory-access in range [0x3fff88e1a3e7bb98-0x3fff88e1a3e7bb9f]
CPU: 0 UID: 0 PID: 999 Comm: kworker/u8:5 Not tainted 6.15.0-rc2-syzkaller-00488-g6fea5fabd332 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events_unbound flush_memcg_stats_dwork
RIP: 0010:cgroup_rstat_push_children kernel/cgroup/rstat.c:165 [inline]
RIP: 0010:cgroup_rstat_updated_list kernel/cgroup/rstat.c:245 [inline]
RIP: 0010:cgroup_rstat_flush+0x871/0x1fa0 kernel/cgroup/rstat.c:325
Code: 00 74 08 48 89 df e8 ee 0d 6f 00 4c 8b 3b 4f 8d 24 2f 49 81 c4 a0 00 00 00 4d 89 e6 49 c1 ee 03 48 b8 00 00 00 00 00 fc ff df <41> 80 3c 06 00 74 08 4c 89 e7 e8 c0 0d 6f 00 4d 01 ef 4d 8b 2c 24
RSP: 0000:ffffc90003907900 EFLAGS: 00010003
RAX: dffffc0000000000 RBX: ffffffff8e786c18 RCX: ffff8880267ada00
RDX: 0000000000000000 RSI: ffffffff8ca0e260 RDI: ffff888058dea5c1
RBP: ffffc90003907b08 R08: ffffffff81bb538b R09: 1ffffffff20bd76e
R10: dffffc0000000000 R11: fffffbfff20bd76f R12: 3fff88e1a3e7bb9c
R13: 400000607edacafc R14: 07fff11c347cf773 R15: ffff8881250cf000
FS:  0000000000000000(0000) GS:ffff888124fcf000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f068e730321 CR3: 00000000587c2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 flush_memcg_stats_dwork+0x15/0x60 mm/memcontrol.c:653
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd50 kernel/workqueue.c:3400
 kthread+0x7b7/0x940 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:cgroup_rstat_push_children kernel/cgroup/rstat.c:165 [inline]
RIP: 0010:cgroup_rstat_updated_list kernel/cgroup/rstat.c:245 [inline]
RIP: 0010:cgroup_rstat_flush+0x871/0x1fa0 kernel/cgroup/rstat.c:325
Code: 00 74 08 48 89 df e8 ee 0d 6f 00 4c 8b 3b 4f 8d 24 2f 49 81 c4 a0 00 00 00 4d 89 e6 49 c1 ee 03 48 b8 00 00 00 00 00 fc ff df <41> 80 3c 06 00 74 08 4c 89 e7 e8 c0 0d 6f 00 4d 01 ef 4d 8b 2c 24
RSP: 0000:ffffc90003907900 EFLAGS: 00010003
RAX: dffffc0000000000 RBX: ffffffff8e786c18 RCX: ffff8880267ada00
RDX: 0000000000000000 RSI: ffffffff8ca0e260 RDI: ffff888058dea5c1
RBP: ffffc90003907b08 R08: ffffffff81bb538b R09: 1ffffffff20bd76e
R10: dffffc0000000000 R11: fffffbfff20bd76f R12: 3fff88e1a3e7bb9c
R13: 400000607edacafc R14: 07fff11c347cf773 R15: ffff8881250cf000
FS:  0000000000000000(0000) GS:ffff888124fcf000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f068e730321 CR3: 00000000587c2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 74 08 48          	add    %dh,0x48(%rax,%rcx,1)
   4:	89 df                	mov    %ebx,%edi
   6:	e8 ee 0d 6f 00       	call   0x6f0df9
   b:	4c 8b 3b             	mov    (%rbx),%r15
   e:	4f 8d 24 2f          	lea    (%r15,%r13,1),%r12
  12:	49 81 c4 a0 00 00 00 	add    $0xa0,%r12
  19:	4d 89 e6             	mov    %r12,%r14
  1c:	49 c1 ee 03          	shr    $0x3,%r14
  20:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  27:	fc ff df
* 2a:	41 80 3c 06 00       	cmpb   $0x0,(%r14,%rax,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 e7             	mov    %r12,%rdi
  34:	e8 c0 0d 6f 00       	call   0x6f0df9
  39:	4d 01 ef             	add    %r13,%r15
  3c:	4d 8b 2c 24          	mov    (%r12),%r13

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/04/20 18:38 upstream 6fea5fabd332 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in cgroup_rstat_flush
2025/04/16 23:37 upstream c62f4b82d571 a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in cgroup_rstat_flush
2025/03/29 18:25 upstream 7d06015d936c d3999433 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in cgroup_rstat_flush
* Struck through repros no longer work on HEAD.