input: syz1 as /devices/virtual/input/input1208 refcount_t: increment on 0; use-after-free. ------------[ cut here ]------------ WARNING: CPU: 0 PID: 5653 at lib/refcount.c:153 refcount_inc lib/refcount.c:153 [inline] WARNING: CPU: 0 PID: 5653 at lib/refcount.c:153 refcount_inc.cold+0x18/0x1f lib/refcount.c:151 kobject: 'tx-0' (ffff8880a53fd058): kobject_uevent_env Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 5653 Comm: syz-executor.5 Not tainted 4.14.151 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x138/0x197 lib/dump_stack.c:53 panic+0x1f9/0x42d kernel/panic.c:183 __warn.cold+0x2f/0x2f kernel/panic.c:547 report_bug+0x216/0x254 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:177 [inline] fixup_bug arch/x86/kernel/traps.c:172 [inline] do_error_trap+0x1bb/0x310 arch/x86/kernel/traps.c:295 kobject: 'tx-0' (ffff8880a53fd058): kobject_uevent_env: uevent_suppress caused the event to drop! do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:963 RIP: 0010:refcount_inc lib/refcount.c:153 [inline] RIP: 0010:refcount_inc.cold+0x18/0x1f lib/refcount.c:151 RSP: 0018:ffff888026eef980 EFLAGS: 00010286 RAX: 000000000000002b RBX: 1ffff11004dddf3d RCX: 0000000000000000 RDX: 000000000000afcc RSI: ffffffff814b3f65 RDI: ffffed1004dddf26 RBP: ffff888026eef988 R08: 000000000000002b R09: ffff88806747aea0 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880942ea720 R13: 0000000000000000 R14: ffff8880847e8d00 R15: ffff8880880f0488 kref_get include/linux/kref.h:47 [inline] kobject_get+0x5b/0x70 lib/kobject.c:596 cdev_get+0x54/0xa0 fs/char_dev.c:364 chrdev_open+0x9b/0x590 fs/char_dev.c:409 do_dentry_open+0x73b/0xeb0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:891 kobject: 'tx-0' (ffff8880a53fd058): auto cleanup kobject_del do_last fs/namei.c:3425 [inline] path_openat+0x8bd/0x3f70 fs/namei.c:3566 kobject: 'tx-0' (ffff8880a53fd058): calling ktype release kobject: 'tx-0': free name do_filp_open+0x18e/0x250 fs/namei.c:3600 kobject: 'queues' (ffff888080356e48): kobject_cleanup, parent (null) do_sys_open+0x2c5/0x430 fs/open.c:1084 SYSC_open fs/open.c:1102 [inline] SyS_open+0x2d/0x40 fs/open.c:1097 kobject: 'queues' (ffff888080356e48): calling ktype release do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x413ce1 RSP: 002b:00007fb48a80b7a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000413ce1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007fb48a80b850 RBP: 000000000075c118 R08: 000000000000000f R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007fb48a80c6d4 R13: 00000000004c97fd R14: 00000000004e1218 R15: 00000000ffffffff Kernel Offset: disabled Rebooting in 86400 seconds..