WARNING in free_ei

Status: moderation: reported on 2026/08/18 04:10
Subsystems: trace fs
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+cafb733a6adbecdbfd4d@syzkaller.appspotmail.com
First crash: 6d04h, last: 15m
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
fcf3f5a9 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ WARNING in free_ei 2026/08/16 00:00 2026/08/16 00:00 2026/08/16 00:34 746171ee

Sample crash report:
Could not create tracefs 'set_event_notrace_pid' entry
------------[ cut here ]------------
!list_empty(&ei->children)
WARNING: fs/tracefs/event_inode.c:128 at free_ei+0x284/0x340 fs/tracefs/event_inode.c:128, CPU#1: syz.4.591/8581
Modules linked in:
CPU: 1 UID: 0 PID: 8581 Comm: syz.4.591 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:free_ei+0x284/0x340 fs/tracefs/event_inode.c:128
Code: 48 c7 c7 00 c1 11 8f 48 89 de 48 c7 c2 e0 94 d9 83 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d e9 32 a5 d1 fd e8 cd 6c ed fd 90 <0f> 0b 90 e9 c7 fd ff ff e8 bf 6c ed fd 90 0f 0b 90 48 b8 00 00 00
RSP: 0018:ffffc9000432fa88 EFLAGS: 00010202
RAX: ffffffff83d99873 RBX: ffff8880752fe210 RCX: ffff888036070000
RDX: 0000000000000003 RSI: ffffffff8c4bdd60 RDI: ffff8880752fe200
RBP: ffff8880752fe200 R08: 00000000ffffffff R09: 1ffffffff20afb46
R10: dffffc0000000000 R11: fffffbfff20afb47 R12: 0000000000000000
R13: ffff888066e81800 R14: ffff8880752fe200 R15: 0000000000000003
FS:  00007f59a15ec6c0(0000) GS:ffff888125036000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8cd675da08 CR3: 000000006f27f000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 cleanup_ei fs/tracefs/event_inode.c:150 [inline]
 eventfs_create_events_dir+0x7c4/0x9f0 fs/tracefs/event_inode.c:834
 create_event_toplevel_files+0x11e/0x1a0 kernel/trace/trace_events.c:4593
 event_trace_add_tracer+0x8a/0x3b0 kernel/trace/trace_events.c:4624
 trace_array_create_dir+0x77/0x160 kernel/trace/trace.c:8548
 trace_array_create_systems+0xb3c/0xe60 kernel/trace/trace.c:8639
 trace_array_create kernel/trace/trace.c:8666 [inline]
 instance_mkdir+0xd5/0x140 kernel/trace/trace.c:8681
 tracefs_syscall_mkdir+0x11a/0x190 fs/tracefs/inode.c:121
 vfs_mkdir+0x40c/0x620 fs/namei.c:5410
 filename_mkdirat+0x285/0x510 fs/namei.c:5443
 __do_sys_mkdirat fs/namei.c:5464 [inline]
 __se_sys_mkdirat+0x35/0x150 fs/namei.c:5461
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f59a079e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f59a15ec028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f59a0a25fa0 RCX: 00007f59a079e0d9
RDX: 00000000000001ff RSI: 0000200000000140 RDI: ffffffffffffff9c
RBP: 00007f59a0835024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f59a0a26038 R14: 00007f59a0a25fa0 R15: 00007ffde26bcc48
 </TASK>

Crashes (26):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/20 08:11 upstream 98f21c54f995 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in free_ei
2026/08/20 08:04 upstream 98f21c54f995 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in free_ei
2026/08/20 08:04 upstream 98f21c54f995 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in free_ei
2026/08/20 07:04 upstream a4ff2be345d0 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/19 18:52 upstream bd5f485f3f02 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/19 18:50 upstream bd5f485f3f02 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/19 08:31 upstream b126f6f5940f 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/18 18:11 upstream 0f23d56f17fd 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/18 09:12 upstream ff68e5f557f6 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/17 12:00 upstream 8d3ae59288f1 905244d6 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/17 11:58 upstream 8d3ae59288f1 905244d6 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/17 11:53 upstream 8d3ae59288f1 905244d6 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/17 11:43 upstream 8d3ae59288f1 905244d6 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/16 21:45 upstream dcb68831eac7 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/16 21:40 upstream dcb68831eac7 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/16 21:40 upstream dcb68831eac7 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/15 15:35 upstream 15ef2f78c49d 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/15 00:15 upstream a5161661ae99 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/15 00:14 upstream a5161661ae99 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/15 00:14 upstream a5161661ae99 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/14 21:10 upstream 2f1baf1fc892 2cf1fbb7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/14 18:27 upstream 2f1baf1fc892 2cf1fbb7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/14 18:25 upstream 2f1baf1fc892 2cf1fbb7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/14 04:01 upstream 3aa1dcaa4f6f b13552fe .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/14 04:01 upstream 3aa1dcaa4f6f b13552fe .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
2026/08/14 04:01 upstream 3aa1dcaa4f6f b13552fe .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in free_ei
* Struck through repros no longer work on HEAD.