================================================================== BUG: KASAN: use-after-free in __list_del_entry_valid+0xe6/0xf5 lib/list_debug.c:51 Read of size 8 at addr ffff8880a1a21ea8 by task syz-executor.1/18892 CPU: 0 PID: 18892 Comm: syz-executor.1 Not tainted 5.2.0-rc3-next-20190607 #11 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0xd4/0x306 mm/kasan/report.c:351 __kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482 kasan_report+0x12/0x20 mm/kasan/common.c:614 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 __list_del_entry_valid+0xe6/0xf5 lib/list_debug.c:51 __list_del_entry include/linux/list.h:117 [inline] list_del include/linux/list.h:125 [inline] unregister_shrinker+0xb2/0x2e0 mm/vmscan.c:443 deactivate_locked_super+0x73/0x100 fs/super.c:330 deactivate_super fs/super.c:362 [inline] deactivate_super+0x1b2/0x1d0 fs/super.c:358 cleanup_mnt+0xbf/0x160 fs/namespace.c:1120 mntput_no_expire fs/namespace.c:1199 [inline] mntput_no_expire+0x7d4/0x960 fs/namespace.c:1141 mntput fs/namespace.c:1209 [inline] kern_unmount fs/namespace.c:3779 [inline] kern_unmount+0xbd/0xf0 fs/namespace.c:3773 mq_put_mnt+0x37/0x41 ipc/mqueue.c:1615 put_ipc_ns ipc/namespace.c:151 [inline] put_ipc_ns+0x5c/0x180 ipc/namespace.c:146 free_nsproxy+0xd3/0x230 kernel/nsproxy.c:180 switch_task_namespaces+0xb3/0xd0 kernel/nsproxy.c:229 exit_task_namespaces+0x18/0x20 kernel/nsproxy.c:234 do_exit+0x905/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x360 kernel/exit.c:981 get_signal+0x463/0x2490 kernel/signal.c:2728 do_signal+0x87/0x1990 arch/x86/kernel/signal.c:815 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x58e/0x680 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459279 Code: Bad RIP value. RSP: 002b:00007f7b9e041cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000075c068 RCX: 0000000000459279 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000075c068 RBP: 000000000075c060 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000075c06c R13: 00007ffef56328cf R14: 00007f7b9e0429c0 R15: 000000000075c06c Allocated by task 18888: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:503 __do_kmalloc mm/slab.c:3654 [inline] __kmalloc+0x15c/0x740 mm/slab.c:3663 kmalloc include/linux/slab.h:552 [inline] kzalloc include/linux/slab.h:742 [inline] ops_init+0xff/0x410 net/core/net_namespace.c:120 setup_net+0x2d3/0x740 net/core/net_namespace.c:316 copy_net_ns+0x1df/0x340 net/core/net_namespace.c:439 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:107 copy_namespaces+0x351/0x3f0 kernel/nsproxy.c:165 copy_process.part.0+0x2c11/0x6720 kernel/fork.c:2060 copy_process kernel/fork.c:1828 [inline] _do_fork+0x25d/0xfe0 kernel/fork.c:2394 __do_sys_clone kernel/fork.c:2501 [inline] __se_sys_clone kernel/fork.c:2495 [inline] __x64_sys_clone+0xbf/0x150 kernel/fork.c:2495 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 18888: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3426 [inline] kfree+0x106/0x2a0 mm/slab.c:3753 ops_init+0xd1/0x410 net/core/net_namespace.c:135 setup_net+0x2d3/0x740 net/core/net_namespace.c:316 copy_net_ns+0x1df/0x340 net/core/net_namespace.c:439 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:107 copy_namespaces+0x351/0x3f0 kernel/nsproxy.c:165 copy_process.part.0+0x2c11/0x6720 kernel/fork.c:2060 copy_process kernel/fork.c:1828 [inline] _do_fork+0x25d/0xfe0 kernel/fork.c:2394 __do_sys_clone kernel/fork.c:2501 [inline] __se_sys_clone kernel/fork.c:2495 [inline] __x64_sys_clone+0xbf/0x150 kernel/fork.c:2495 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880a1a21b40 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 872 bytes inside of 1024-byte region [ffff8880a1a21b40, ffff8880a1a21f40) The buggy address belongs to the page: page:ffffea0002868800 refcount:1 mapcount:0 mapping:ffff8880aa400ac0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0002910f88 ffffea0002168888 ffff8880aa400ac0 raw: 0000000000000000 ffff8880a1a20040 0000000100000007 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a1a21d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a1a21e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880a1a21e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a1a21f00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880a1a21f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================