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: 5d18h, last: 5d18h

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xe7ffed1c347b351d: 0000 [#1] SMP KASAN PTI
KASAN: maybe wild-memory-access in range [0x3fff88e1a3d9a8e8-0x3fff88e1a3d9a8ef]
CPU: 0 UID: 0 PID: 5932 Comm: syz.4.9 Not tainted 6.14.0-syzkaller-09584-g7d06015d936c #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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+0x865/0x1fa0 kernel/cgroup/rstat.c:321
Code: 00 74 08 48 89 df e8 ca 0e 6d 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 9c 0e 6d 00 4d 01 ef 4d 8b 2c 24
RSP: 0018:ffffc9000454f380 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: ffffffff8e774b90 RCX: 0000000000080000
RDX: ffffc9000d734000 RSI: 0000000000038299 RDI: ffff88802adfe5c1
RBP: ffffc9000454f590 R08: ffffffff81bc21df R09: 1ffffffff20bc0ae
R10: dffffc0000000000 R11: fffffbfff20bc0af R12: 3fff88e1a3d9a8e9
R13: 400000607edac849 R14: 07fff11c347b351d R15: ffff888124fee000
FS:  00007f89286926c0(0000) GS:ffff888124fee000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055592e7364f8 CR3: 000000007e230000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 zswap_shrinker_count+0x235/0x5d0 mm/zswap.c:1272
 do_shrink_slab+0x84/0x1140 mm/shrinker.c:384
 shrink_slab+0x1097/0x14e0 mm/shrinker.c:664
 drop_slab_node mm/vmscan.c:421 [inline]
 drop_slab+0x142/0x280 mm/vmscan.c:439
 drop_caches_sysctl_handler+0xbc/0x160 fs/drop_caches.c:68
 proc_sys_call_handler+0x60a/0x950 fs/proc/proc_sysctl.c:601
 do_iter_readv_writev+0x71f/0x9d0 fs/read_write.c:-1
 vfs_writev+0x38d/0xbc0 fs/read_write.c:1055
 do_writev+0x1b8/0x360 fs/read_write.c:1101
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f892778d169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8928692038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f89279a5fa0 RCX: 00007f892778d169
RDX: 0000000000000001 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f892780e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f89279a5fa0 R15: 00007ffe6544ecc8
 </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+0x865/0x1fa0 kernel/cgroup/rstat.c:321
Code: 00 74 08 48 89 df e8 ca 0e 6d 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 9c 0e 6d 00 4d 01 ef 4d 8b 2c 24
RSP: 0018:ffffc9000454f380 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: ffffffff8e774b90 RCX: 0000000000080000
RDX: ffffc9000d734000 RSI: 0000000000038299 RDI: ffff88802adfe5c1
RBP: ffffc9000454f590 R08: ffffffff81bc21df R09: 1ffffffff20bc0ae
R10: dffffc0000000000 R11: fffffbfff20bc0af R12: 3fff88e1a3d9a8e9
R13: 400000607edac849 R14: 07fff11c347b351d R15: ffff888124fee000
FS:  00007f89286926c0(0000) GS:ffff888124fee000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055592e7364f8 CR3: 000000007e230000 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 ca 0e 6d 00       	call   0x6d0ed5
   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 9c 0e 6d 00       	call   0x6d0ed5
  39:	4d 01 ef             	add    %r13,%r15
  3c:	4d 8b 2c 24          	mov    (%r12),%r13

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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.