ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 non-slab/vmalloc memory list_del corruption. prev->next should be ffffc90003567c50, but was 0000000000000000. (prev=ffff8880368e80a8) ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:62! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI CPU: 1 UID: 0 PID: 11779 Comm: khidpd_00050001 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:__list_del_entry_valid_or_report+0x14a/0x1d0 lib/list_debug.c:62 Code: 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 8d 00 00 00 48 8b 55 00 48 89 e9 48 89 de 48 c7 c7 40 fa 1a 8c e8 87 c2 25 fc 90 <0f> 0b 4c 89 e7 e8 fc 7c 52 fd 48 89 ea 48 b8 00 00 00 00 00 fc ff RSP: 0018:ffffc90003567b20 EFLAGS: 00010082 RAX: 000000000000006d RBX: ffffc90003567c50 RCX: 0000000000000000 RDX: 000000000000006d RSI: ffffffff81e77f29 RDI: fffff520006acf55 RBP: ffff8880368e80a8 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000002 R11: 6c65645f7473696c R12: ffff8880368e80a8 R13: 0000000000000246 R14: ffffc90003567c50 R15: ffff888059283d00 FS: 0000000000000000(0000) GS:ffff888124445000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c35b446 CR3: 000000002b160000 CR4: 0000000000350ef0 Call Trace: __list_del_entry_valid include/linux/list.h:132 [inline] __list_del_entry include/linux/list.h:223 [inline] list_del include/linux/list.h:237 [inline] __mutex_remove_waiter+0x1a/0x1a0 kernel/locking/mutex.c:221 __mutex_lock_common kernel/locking/mutex.c:742 [inline] __mutex_lock+0x828/0x1b90 kernel/locking/mutex.c:776 l2cap_unregister_user+0x71/0x240 net/bluetooth/l2cap_core.c:1721 hidp_session_thread+0x459/0x680 net/bluetooth/hidp/core.c:1304 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__list_del_entry_valid_or_report+0x14a/0x1d0 lib/list_debug.c:62 Code: 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 8d 00 00 00 48 8b 55 00 48 89 e9 48 89 de 48 c7 c7 40 fa 1a 8c e8 87 c2 25 fc 90 <0f> 0b 4c 89 e7 e8 fc 7c 52 fd 48 89 ea 48 b8 00 00 00 00 00 fc ff RSP: 0018:ffffc90003567b20 EFLAGS: 00010082 RAX: 000000000000006d RBX: ffffc90003567c50 RCX: 0000000000000000 RDX: 000000000000006d RSI: ffffffff81e77f29 RDI: fffff520006acf55 RBP: ffff8880368e80a8 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000002 R11: 6c65645f7473696c R12: ffff8880368e80a8 R13: 0000000000000246 R14: ffffc90003567c50 R15: ffff888059283d00 FS: 0000000000000000(0000) GS:ffff888124445000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c35b446 CR3: 000000002b160000 CR4: 0000000000350ef0