===================================== WARNING: bad unlock balance detected! syzkaller #0 Not tainted ------------------------------------- syz.2.868/8722 is trying to release lock (&sighand->siglock) at: [] spin_unlock include/linux/spinlock.h:391 [inline] [] copy_process+0x2793/0x3c00 kernel/fork.c:2432 but there are no more locks to release! other info that might help us debug this: 1 lock held by syz.2.868/8722: #0: ffffffff8e171810 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x212a/0x3c00 kernel/fork.c:2274 stack backtrace: CPU: 0 UID: 0 PID: 8722 Comm: syz.2.868 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_unlock_imbalance_bug+0xdc/0xf0 kernel/locking/lockdep.c:5298 __lock_release kernel/locking/lockdep.c:5537 [inline] lock_release+0x269/0x3e0 kernel/locking/lockdep.c:5889 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline] _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] copy_process+0x2793/0x3c00 kernel/fork.c:2432 kernel_clone+0x21e/0x840 kernel/fork.c:2605 __do_sys_clone3 kernel/fork.c:2909 [inline] __se_sys_clone3+0x256/0x2d0 kernel/fork.c:2888 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f48ac7c3609 Code: d7 08 00 48 8d 3d 9c d7 08 00 e8 e2 28 f6 ff 66 90 b8 ea ff ff ff 48 85 ff 74 2c 48 85 d2 74 27 49 89 c8 b8 b3 01 00 00 0f 05 <48> 85 c0 7c 18 74 01 c3 31 ed 48 83 e4 f0 4c 89 c7 ff d2 48 89 c7 RSP: 002b:00007ffd18341778 EFLAGS: 00000206 ORIG_RAX: 00000000000001b3 RAX: ffffffffffffffda RBX: 00007f48ac7459f0 RCX: 00007f48ac7c3609 RDX: 00007f48ac7459f0 RSI: 0000000000000058 RDI: 00007ffd183417c0 RBP: 00007f48ad6276c0 R08: 00007f48ad6276c0 R09: 00007ffd183418a7 R10: 0000000000000008 R11: 0000000000000206 R12: ffffffffffffffa8 R13: 000000000000000b R14: 00007ffd183417c0 R15: 00007ffd183418a8 ------------[ cut here ]------------ pvqspinlock: lock 0xffff888029a76f00 has corrupted value 0x0! WARNING: CPU: 1 PID: 8722 at kernel/locking/qspinlock_paravirt.h:506 __pv_queued_spin_unlock_slowpath+0x1fe/0x2a0 kernel/locking/qspinlock_paravirt.h:504 Modules linked in: CPU: 1 UID: 0 PID: 8722 Comm: syz.2.868 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:__pv_queued_spin_unlock_slowpath+0x1fe/0x2a0 kernel/locking/qspinlock_paravirt.h:504 Code: 58 ba ac f6 48 89 d8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 93 00 00 00 8b 13 48 c7 c7 00 0c 8b 8b 48 89 de e8 d3 d1 0c f6 90 <0f> 0b 90 90 eb 95 48 c7 c7 90 c5 00 8e 4c 89 f6 4c 89 fa e8 ca 64 RSP: 0018:ffffc9001b3478c0 EFLAGS: 00010246 RAX: 80fb57d29651d500 RBX: ffff888029a76f00 RCX: ffff88802afdbc00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002 RBP: 1ffff1100534ede1 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff1bfa22c R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff888029a76f10 R15: ffff888029a76f08 FS: 000055557ef32500(0000) GS:ffff888125d39000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055556de085c8 CR3: 000000007873e000 CR4: 00000000003526f0 Call Trace: __raw_callee_save___pv_queued_spin_unlock_slowpath+0x15/0x30 .slowpath+0x9/0x18 pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:562 [inline] queued_spin_unlock arch/x86/include/asm/qspinlock.h:57 [inline] do_raw_spin_unlock+0x122/0x240 kernel/locking/spinlock_debug.c:142 __raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_unlock+0x1e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] copy_process+0x2793/0x3c00 kernel/fork.c:2432 kernel_clone+0x21e/0x840 kernel/fork.c:2605 __do_sys_clone3 kernel/fork.c:2909 [inline] __se_sys_clone3+0x256/0x2d0 kernel/fork.c:2888 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f48ac7c3609 Code: d7 08 00 48 8d 3d 9c d7 08 00 e8 e2 28 f6 ff 66 90 b8 ea ff ff ff 48 85 ff 74 2c 48 85 d2 74 27 49 89 c8 b8 b3 01 00 00 0f 05 <48> 85 c0 7c 18 74 01 c3 31 ed 48 83 e4 f0 4c 89 c7 ff d2 48 89 c7 RSP: 002b:00007ffd18341778 EFLAGS: 00000206 ORIG_RAX: 00000000000001b3 RAX: ffffffffffffffda RBX: 00007f48ac7459f0 RCX: 00007f48ac7c3609 RDX: 00007f48ac7459f0 RSI: 0000000000000058 RDI: 00007ffd183417c0 RBP: 00007f48ad6276c0 R08: 00007f48ad6276c0 R09: 00007ffd183418a7 R10: 0000000000000008 R11: 0000000000000206 R12: ffffffffffffffa8 R13: 000000000000000b R14: 00007ffd183417c0 R15: 00007ffd183418a8