===================================== WARNING: bad unlock balance detected! syzkaller #0 Not tainted ------------------------------------- syz.5.1276/10645 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.5.1276/10645: #0: ffffffff8e171810 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x212a/0x3c00 kernel/fork.c:2274 stack backtrace: CPU: 1 UID: 0 PID: 10645 Comm: syz.5.1276 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: 0033:0x7fc5e91c3409 Code: d8 08 00 48 8d 3d 1c d8 08 00 e8 12 29 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:00007ffc943f8a58 EFLAGS: 00000202 ORIG_RAX: 00000000000001b3 RAX: ffffffffffffffda RBX: 00007fc5e9145820 RCX: 00007fc5e91c3409 RDX: 00007fc5e9145820 RSI: 0000000000000058 RDI: 00007ffc943f8aa0 RBP: 00007fc5ea08b6c0 R08: 00007fc5ea08b6c0 R09: 00007ffc943f8b87 R10: 0000000000000008 R11: 0000000000000202 R12: ffffffffffffffa8 R13: 000000000000000b R14: 00007ffc943f8aa0 R15: 00007ffc943f8b88 ------------[ cut here ]------------ pvqspinlock: lock 0xffff88802eb83780 has corrupted value 0x0! WARNING: CPU: 0 PID: 10645 at kernel/locking/qspinlock_paravirt.h:506 __pv_queued_spin_unlock_slowpath+0x1fe/0x2a0 kernel/locking/qspinlock_paravirt.h:504 Modules linked in: CPU: 0 UID: 0 PID: 10645 Comm: syz.5.1276 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: a8 3b a6 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 61 06 f6 90 <0f> 0b 90 90 eb 95 48 c7 c7 90 c5 00 8e 4c 89 f6 4c 89 fa e8 0a c1 RSP: 0018:ffffc900033678c0 EFLAGS: 00010246 RAX: cbd202ff56aaf800 RBX: ffff88802eb83780 RCX: ffff88805b3f8000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002 RBP: 1ffff11005d706f1 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff1bfa22c R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff88802eb83790 R15: ffff88802eb83788 FS: 000055556bca6500(0000) GS:ffff888125c15000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055556bcb9588 CR3: 000000007c52e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 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: 0033:0x7fc5e91c3409 Code: d8 08 00 48 8d 3d 1c d8 08 00 e8 12 29 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:00007ffc943f8a58 EFLAGS: 00000202 ORIG_RAX: 00000000000001b3 RAX: ffffffffffffffda RBX: 00007fc5e9145820 RCX: 00007fc5e91c3409 RDX: 00007fc5e9145820 RSI: 0000000000000058 RDI: 00007ffc943f8aa0 RBP: 00007fc5ea08b6c0 R08: 00007fc5ea08b6c0 R09: 00007ffc943f8b87 R10: 0000000000000008 R11: 0000000000000202 R12: ffffffffffffffa8 R13: 000000000000000b R14: 00007ffc943f8aa0 R15: 00007ffc943f8b88