IPVS: Creating netns size=2552 id=80
==================================================================
BUG: KASAN: use-after-free in link_path_walk+0x1375/0x1710 fs/namei.c:1949
Read of size 4 at addr ffff8800ba2126e0 by task syz-executor2/13198

CPU: 0 PID: 13198 Comm: syz-executor2 Not tainted 4.4.145-g2241aa9 #14
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 f53a467d5f65c21f ffff8801d1f37890 ffffffff81e123cd
 ffffea0002e88480 ffff8800ba2126e0 0000000000000000 ffff8800ba2126e0
 ffff8801d1f37c70 ffff8801d1f378c8 ffffffff81517d66 ffff8800ba2126e0
Call Trace:
 [<ffffffff81e123cd>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81e123cd>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff81517d66>] print_address_description+0x6c/0x216 mm/kasan/report.c:252
 [<ffffffff81518085>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff81518085>] kasan_report.cold.7+0x175/0x2f7 mm/kasan/report.c:408
 [<ffffffff814fbb54>] __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:428
 [<ffffffff8154cf35>] link_path_walk+0x1375/0x1710 fs/namei.c:1949
 [<ffffffff8154e204>] path_openat+0x1a4/0x3a10 fs/namei.c:3358
 [<ffffffff81554787>] do_filp_open+0x197/0x270 fs/namei.c:3393
 [<ffffffff8151ddcc>] do_sys_open+0x31c/0x610 fs/open.c:1038
 [<ffffffff8162925d>] C_SYSC_openat fs/compat.c:1101 [inline]
 [<ffffffff8162925d>] compat_SyS_openat+0x2d/0x40 fs/compat.c:1099
 [<ffffffff81006d94>] do_syscall_32_irqs_on arch/x86/entry/common.c:393 [inline]
 [<ffffffff81006d94>] do_fast_syscall_32+0x324/0x8b0 arch/x86/entry/common.c:460
 [<ffffffff838c9e43>] sysenter_flags_fixed+0xd/0x1a

Allocated by task 13186:
 [<ffffffff81034676>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814fac23>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814faf07>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814faf07>] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:616
 [<ffffffff814fb4d2>] kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:554
 [<ffffffff814f6fce>] slab_post_alloc_hook mm/slub.c:1349 [inline]
 [<ffffffff814f6fce>] slab_alloc_node mm/slub.c:2615 [inline]
 [<ffffffff814f6fce>] slab_alloc mm/slub.c:2623 [inline]
 [<ffffffff814f6fce>] kmem_cache_alloc+0xbe/0x2a0 mm/slub.c:2628
 [<ffffffff8156cdde>] __d_alloc+0x2e/0x7b0 fs/dcache.c:1589
 [<ffffffff8156d807>] d_make_root+0x47/0x90 fs/dcache.c:1956
 [<ffffffff81844f7d>] ramfs_fill_super+0x35d/0x490 fs/ramfs/inode.c:232
 [<ffffffff81528e2b>] mount_nodev+0x5b/0x100 fs/super.c:1086
 [<ffffffff8184441c>] ramfs_mount+0x2c/0x40 fs/ramfs/inode.c:242
 [<ffffffff8152ae5c>] mount_fs+0x28c/0x370 fs/super.c:1146
 [<ffffffff81582e51>] vfs_kern_mount.part.30+0xd1/0x3d0 fs/namespace.c:991
 [<ffffffff8158a49e>] vfs_kern_mount fs/namespace.c:973 [inline]
 [<ffffffff8158a49e>] do_new_mount fs/namespace.c:2517 [inline]
 [<ffffffff8158a49e>] do_mount+0x4ee/0x2860 fs/namespace.c:2833
 [<ffffffff8162811a>] C_SYSC_mount fs/compat.c:824 [inline]
 [<ffffffff8162811a>] compat_SyS_mount+0x57a/0x1040 fs/compat.c:789
 [<ffffffff81006d94>] do_syscall_32_irqs_on arch/x86/entry/common.c:393 [inline]
 [<ffffffff81006d94>] do_fast_syscall_32+0x324/0x8b0 arch/x86/entry/common.c:460
 [<ffffffff838c9e43>] sysenter_flags_fixed+0xd/0x1a

Freed by task 13201:
 [<ffffffff81034676>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814fac23>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814fb552>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814fb552>] kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:589
 [<ffffffff814f86de>] slab_free_hook mm/slub.c:1383 [inline]
 [<ffffffff814f86de>] slab_free_freelist_hook mm/slub.c:1405 [inline]
 [<ffffffff814f86de>] slab_free mm/slub.c:2859 [inline]
 [<ffffffff814f86de>] kmem_cache_free+0xbe/0x340 mm/slub.c:2881
 [<ffffffff815643d5>] __d_free fs/dcache.c:257 [inline]
 [<ffffffff815643d5>] dentry_free+0xd5/0x150 fs/dcache.c:333
 [<ffffffff8156659c>] __dentry_kill+0x4ac/0x5f0 fs/dcache.c:576
 [<ffffffff81569e77>] dentry_kill fs/dcache.c:603 [inline]
 [<ffffffff81569e77>] dput.part.26+0x587/0x760 fs/dcache.c:818
 [<ffffffff8156bec3>] dput fs/dcache.c:782 [inline]
 [<ffffffff8156bec3>] do_one_tree+0x43/0x50 fs/dcache.c:1473
 [<ffffffff8156cce2>] shrink_dcache_for_umount+0x62/0x130 fs/dcache.c:1487
 [<ffffffff8152647d>] generic_shutdown_super+0x6d/0x300 fs/super.c:413
 [<ffffffff81526d02>] kill_anon_super fs/super.c:914 [inline]
 [<ffffffff81526d02>] kill_litter_super+0x72/0x90 fs/super.c:924
 [<ffffffff818443df>] ramfs_kill_sb+0x3f/0x50 fs/ramfs/inode.c:248
 [<ffffffff815271dd>] deactivate_locked_super+0x8d/0xd0 fs/super.c:301
 [<ffffffff81527b21>] deactivate_super+0x91/0xd0 fs/super.c:332
 [<ffffffff81582102>] cleanup_mnt+0xb2/0x160 fs/namespace.c:1119
 [<ffffffff81582236>] __cleanup_mnt+0x16/0x20 fs/namespace.c:1126
 [<ffffffff8118e00f>] task_work_run+0x10f/0x190 kernel/task_work.c:115
 [<ffffffff8100362d>] tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 [<ffffffff8100362d>] exit_to_usermode_loop+0x13d/0x160 arch/x86/entry/common.c:253
 [<ffffffff8100708e>] prepare_exit_to_usermode arch/x86/entry/common.c:284 [inline]
 [<ffffffff8100708e>] syscall_return_slowpath arch/x86/entry/common.c:349 [inline]
 [<ffffffff8100708e>] do_syscall_32_irqs_on arch/x86/entry/common.c:399 [inline]
 [<ffffffff8100708e>] do_fast_syscall_32+0x61e/0x8b0 arch/x86/entry/common.c:460
 [<ffffffff838c9e43>] sysenter_flags_fixed+0xd/0x1a

The buggy address belongs to the object at ffff8800ba2126e0
 which belongs to the cache dentry of size 288
The buggy address is located 0 bytes inside of
 288-byte region [ffff8800ba2126e0, ffff8800ba212800)
The buggy address belongs to the page:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 3888 Comm: syz-executor0 Not tainted 4.4.145-g2241aa9 #14
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d926c800 task.stack: ffff8800a5168000
RIP: 0010:[<ffffffff81e2304d>]  [<ffffffff81e2304d>] ____rb_erase_color lib/rbtree.c:263 [inline]
RIP: 0010:[<ffffffff81e2304d>]  [<ffffffff81e2304d>] rb_erase+0x2ed/0x1cb0 lib/rbtree.c:429
RSP: 0000:ffff8800a516f528  EFLAGS: 00010007
RAX: 00000000841f0f2e RBX: dffffc0000000000 RCX: ffff8801d130e078
RDX: ffffed003b663ec2 RSI: ffff8801db31f610 RDI: 0cc003e1fa7d6000
RBP: ffff8800a516f570 R08: 1ffffffff0291e59 R09: ffff8801db31f540
R10: ffff8801db31f5e8 R11: ffff8801d926ca70 R12: ffff8801d130e070
R13: ffffffff8148f2c7 R14: 66001f0fd3eb0006 R15: ffffffff8148f2d7
FS:  0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000008360a80 CR3: 00000000a5580000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 0000000000000001 ffff8801baf048c8 ffff8801baf048e0 ffff8801baf048c8
 ffff8801baf04860 ffff8801db31f5e8 ffff8801baf04870 ffff8801db31f618
 ffff8801db31f540 ffff8800a516f5a8 ffffffff811e577f ffff8801d926c860
Call Trace:
 [<ffffffff811e577f>] __dequeue_entity kernel/sched/fair.c:589 [inline]
 [<ffffffff811e577f>] set_next_entity+0x2af/0x3d0 kernel/sched/fair.c:3688
 [<ffffffff811ff789>] pick_next_task_fair+0x1159/0x1fc0 kernel/sched/fair.c:7089
 [<ffffffff838b885e>] pick_next_task kernel/sched/core.c:3178 [inline]
 [<ffffffff838b885e>] __schedule+0x31e/0x1d70 kernel/sched/core.c:3308
 [<ffffffff838ba2d2>] preempt_schedule_common+0x22/0x60 kernel/sched/core.c:3396
 [<ffffffff838ba335>] preempt_schedule+0x25/0x30 kernel/sched/core.c:3421
 [<ffffffff81003058>] ___preempt_schedule+0x12/0x14
 [<ffffffff81497fe0>] spin_unlock include/linux/spinlock.h:347 [inline]
 [<ffffffff81497fe0>] zap_pte_range mm/memory.c:1207 [inline]
 [<ffffffff81497fe0>] zap_pmd_range mm/memory.c:1262 [inline]
 [<ffffffff81497fe0>] zap_pud_range mm/memory.c:1283 [inline]
 [<ffffffff81497fe0>] unmap_page_range mm/memory.c:1307 [inline]
 [<ffffffff81497fe0>] unmap_single_vma+0xc50/0x1250 mm/memory.c:1352
 [<ffffffff8149a101>] unmap_vmas+0x81/0xd0 mm/memory.c:1382
 [<ffffffff814b2639>] exit_mmap+0x1c9/0x3a0 mm/mmap.c:2958
 [<ffffffff811276d8>] __mmput kernel/fork.c:717 [inline]
 [<ffffffff811276d8>] mmput+0xf8/0x2d0 kernel/fork.c:737
 [<ffffffff81137368>] exit_mm kernel/exit.c:440 [inline]
 [<ffffffff81137368>] do_exit+0x8d8/0x26b0 kernel/exit.c:742
 [<ffffffff8113d3b1>] do_group_exit+0x111/0x330 kernel/exit.c:885
 [<ffffffff811607ac>] get_signal+0x4ec/0x14b0 kernel/signal.c:2321
 [<ffffffff8100df4b>] do_signal+0x8b/0x1d30 arch/x86/kernel/signal.c:712
 [<ffffffff8100360a>] exit_to_usermode_loop+0x11a/0x160 arch/x86/entry/common.c:249
 [<ffffffff81006363>] prepare_exit_to_usermode+0xe3/0x100 arch/x86/entry/common.c:284
 [<ffffffff838c9088>] retint_user+0x8/0x3c
Code: 84 f4 01 00 00 49 8d 7d 08 49 89 f8 49 c1 e8 03 41 80 3c 18 00 0f 85 26 0f 00 00 4d 8b 75 08 4d 85 f6 74 1b 4c 89 f7 48 c1 ef 03 <80> 3c 1f 00 0f 85 f8 0c 00 00 41 f6 06 01 0f 84 5a 09 00 00 48 
RIP  [<ffffffff81e2304d>] ____rb_erase_color lib/rbtree.c:263 [inline]
RIP  [<ffffffff81e2304d>] rb_erase+0x2ed/0x1cb0 lib/rbtree.c:429
 RSP <ffff8800a516f528>
---[ end trace f4dcfac929fe6217 ]---