WARNING in bpf_tracing_link_release

Status: upstream: reported C repro on 2026/09/15 20:49
Reported-by: syzbot+758122b4b9bfec085f84@syzkaller.appspotmail.com
First crash: 3d05h, last: 3d04h
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 WARNING in bpf_tracing_link_release -1 syz, C 3 4d08h 4d14h 0/2 upstream: reported C repro on 2026/09/14 12:18

Sample crash report:
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007f847a025fac R14: 00007f847a025fa0 R15: 00007f847a025fa0
 </TASK>
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4428 at kernel/bpf/syscall.c:2954 bpf_tracing_link_release+0xc2/0xd0 kernel/bpf/syscall.c:2953
Modules linked in:
CPU: 1 PID: 4428 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:bpf_tracing_link_release+0xc2/0xd0 kernel/bpf/syscall.c:2953
Code: 74 15 e8 b1 f1 f0 ff 48 89 df 5b 41 5c 41 5e 41 5f 5d e9 41 b9 fe ff e8 9c f1 f0 ff 5b 41 5c 41 5e 41 5f 5d c3 e8 8e f1 f0 ff <0f> 0b 43 80 3c 3c 00 75 96 eb 9c 0f 1f 00 53 48 89 fb e8 77 f1 f0
RSP: 0018:ffffc90003497d10 EFLAGS: 00010293
RAX: ffffffff81914152 RBX: ffff888077c11800 RCX: ffff888078f95a00
RDX: 0000000000000000 RSI: 00000000fffffff4 RDI: 0000000000000000
RBP: 00000000fffffff4 R08: ffffc90003497c47 R09: 1ffff92000692f88
R10: dffffc0000000000 R11: fffff52000692f89 R12: 1ffff1100ef82311
R13: 1ffff1100ef82303 R14: ffff888077c11888 R15: dffffc0000000000
FS:  0000555574083500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8479c70050 CR3: 000000007c4ee000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 bpf_link_free kernel/bpf/syscall.c:2769 [inline]
 bpf_link_put+0x22a/0x2c0 kernel/bpf/syscall.c:2795
 bpf_link_release+0x37/0x40 kernel/bpf/syscall.c:2804
 __fput+0x20a/0x8b0 fs/file_table.c:320
 task_work_run+0x1d0/0x260 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:180
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:213
 __syscall_exit_to_user_mode_work kernel/entry/common.c:295 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:306
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8479d9e159
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:00007fff559274f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00007f847a025fa0 RCX: 00007f8479d9e159
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fff55927560 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007f847a025fac R14: 00007f847a025fa0 R15: 00007f847a025fa0
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/15 21:41 linux-6.1.y 1a8763b93150 2daa4bb5 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in bpf_tracing_link_release
2026/09/15 20:48 linux-6.1.y 1a8763b93150 2daa4bb5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in bpf_tracing_link_release
* Struck through repros no longer work on HEAD.