audit: type=1400 audit(1513711436.700:7): avc: denied { map } for pid=3124 comm="syzkaller396275" path="/root/syzkaller396275826" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 ------------[ cut here ]------------ refcount_t: increment on 0; use-after-free. WARNING: CPU: 1 PID: 3125 at lib/refcount.c:153 refcount_inc+0x47/0x50 lib/refcount.c:153 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 3125 Comm: syzkaller396275 Not tainted 4.15.0-rc3-next-20171214+ #67 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+0xe9/0x14b lib/dump_stack.c:53 panic+0x10e/0x2f8 kernel/panic.c:183 __warn+0x14e/0x150 kernel/panic.c:547 report_bug+0x11e/0x1a0 lib/bug.c:184 fixup_bug.part.11+0x17/0x30 arch/x86/kernel/traps.c:177 fixup_bug arch/x86/kernel/traps.c:246 [inline] do_error_trap+0x14a/0x180 arch/x86/kernel/traps.c:295 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314 invalid_op+0x22/0x40 arch/x86/entry/entry_64.S:1079 RIP: 0010:refcount_inc+0x47/0x50 lib/refcount.c:153 RSP: 0018:ffffc9000186bb90 EFLAGS: 00010282 RAX: 000000000000002b RBX: ffff880214e2f800 RCX: ffffffff8123dede RDX: 0000000000000000 RSI: ffff880214d5f018 RDI: 0000000000000293 RBP: ffffc9000186bb98 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc9000186bb18 R11: 0000000000000000 R12: ffffffff8162ef10 R13: ffff8802156d2578 R14: ffff8802156d2600 R15: 0000000000000001 get_ipc_ns include/linux/ipc_namespace.h:129 [inline] __get_ns_from_inode ipc/mqueue.c:110 [inline] get_ns_from_inode ipc/mqueue.c:118 [inline] mqueue_evict_inode+0x69/0x340 ipc/mqueue.c:402 evict+0x102/0x230 fs/inode.c:552 iput_final fs/inode.c:1514 [inline] iput+0x32b/0x400 fs/inode.c:1541 dentry_unlink_inode+0x1ab/0x1e0 fs/dcache.c:375 __dentry_kill+0x12d/0x210 fs/dcache.c:572 shrink_dentry_list+0x140/0x660 fs/dcache.c:1019 shrink_dcache_parent+0x2f/0x90 fs/dcache.c:1453 do_one_tree+0x15/0x50 fs/dcache.c:1484 shrink_dcache_for_umount+0x37/0xb0 fs/dcache.c:1501 generic_shutdown_super+0x2d/0x170 fs/super.c:424 kill_anon_super fs/super.c:987 [inline] kill_litter_super+0x36/0x50 fs/super.c:997 deactivate_locked_super+0x4d/0x80 fs/super.c:312 deactivate_super+0x61/0x90 fs/super.c:343 cleanup_mnt+0x49/0x90 fs/namespace.c:1173 __cleanup_mnt+0x16/0x20 fs/namespace.c:1180 task_work_run+0xa3/0xe0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x3e6/0x1050 kernel/exit.c:869 do_group_exit+0x60/0x100 kernel/exit.c:972 SYSC_exit_group kernel/exit.c:983 [inline] SyS_exit_group+0x18/0x20 kernel/exit.c:981 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x4406f9 RSP: 002b:00007ffde12b8798 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00000000004406f9 RDX: 00000000004406f9 RSI: 00000000004406f9 RDI: 0000000000000001 RBP: 00000000006cb018 R08: 0000000000000000 R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000401bc0 R13: 0000000000401c50 R14: 0000000000000000 R15: 0000000000000000 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds..