syzbot

==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: slab-use-after-free in atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1383 [inline]
BUG: KASAN: slab-use-after-free in gfs2_qd_dealloc+0x81/0xe0 fs/gfs2/quota.c:112
Write of size 4 at addr ffff888012448b68 by task udevd/4737

CPU: 0 UID: 0 PID: 4737 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <IRQ>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:200
 instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
 atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1383 [inline]
 gfs2_qd_dealloc+0x81/0xe0 fs/gfs2/quota.c:112
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core+0xd70/0x1870 kernel/rcu/tree.c:2857
 handle_softirqs+0x27d/0x850 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:stack_trace_consume_entry+0xa2/0x280 kernel/stacktrace.c:93
Code: cc 41 0f b6 04 17 84 c0 0f 85 78 01 00 00 44 89 23 b0 01 e9 99 00 00 00 31 c0 e9 92 00 00 00 48 89 f8 48 c1 e8 03 80 3c 10 00 <74> 29 49 89 ff 48 89 74 24 08 49 89 d4 4c 89 04 24 4c 89 cb e8 55
RSP: 0018:ffffc9000271f378 EFLAGS: 00000246
RAX: 1ffff920004e3e90 RBX: ffffc9000271f48c RCX: a8ffc95ddb968900
RDX: dffffc0000000000 RSI: ffffffff823e5756 RDI: ffffc9000271f480
RBP: 1ffff920004e3e92 R08: ffffc9000271f490 R09: 0000000000000005
R10: ffffc9000271f418 R11: ffffffff81ad9fb0 R12: 0000000000000000
R13: 1ffff920004e3e91 R14: ffffc9000271f488 R15: 1ffff920004e3e91
 arch_stack_walk+0x110/0x150 arch/x86/kernel/stacktrace.c:27
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4948 [inline]
 slab_alloc_node mm/slub.c:5258 [inline]
 kmem_cache_alloc_lru_noprof+0x36c/0x6e0 mm/slub.c:5277
 __d_alloc+0x37/0x6f0 fs/dcache.c:1730
 d_alloc_parallel+0xe1/0x1610 fs/dcache.c:2594
 __lookup_slow+0x116/0x3d0 fs/namei.c:1843
 lookup_slow+0x53/0x70 fs/namei.c:1875
 walk_component fs/namei.c:2221 [inline]
 lookup_last fs/namei.c:2722 [inline]
 path_lookupat+0x3f5/0x8c0 fs/namei.c:2746
 filename_lookup+0x212/0x570 fs/namei.c:2775
 do_readlinkat+0xd9/0x500 fs/stat.c:576
 __do_sys_readlink fs/stat.c:613 [inline]
 __se_sys_readlink fs/stat.c:610 [inline]
 __x64_sys_readlink+0x7f/0x90 fs/stat.c:610
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0078b153a7
Code: 00 00 90 48 83 ec 10 48 63 ff 45 31 c9 45 31 c0 6a 00 31 c9 e8 8a 20 f9 ff 48 83 c4 18 c3 0f 1f 44 00 00 b8 59 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 21 ba 0d 00 f7 d8 64 89 02 48
RSP: 002b:00007ffddb25b7e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000059
RAX: ffffffffffffffda RBX: 00007ffddb25bcc0 RCX: 00007f0078b153a7
RDX: 0000000000000400 RSI: 00007ffddb25b7f0 RDI: 00007ffddb25bcc0
RBP: 00007ffddb25b7f0 R08: 00005624bd4fbb60 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000400
R13: 0000000000000100 R14: 00005624b341cbe0 R15: 00007ffddb25c740
 </TASK>

Allocated by task 5743:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 poison_kmalloc_redzone mm/kasan/common.c:397 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414
 kasan_kmalloc include/linux/kasan.h:262 [inline]
 __kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5771
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 init_sbd fs/gfs2/ops_fstype.c:79 [inline]
 gfs2_fill_super+0x11f/0x21b0 fs/gfs2/ops_fstype.c:1121
 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691
 gfs2_get_tree+0x51/0x1e0 fs/gfs2/ops_fstype.c:1332
 vfs_get_tree+0x92/0x2a0 fs/super.c:1751
 fc_mount fs/namespace.c:1199 [inline]
 do_new_mount_fc fs/namespace.c:3636 [inline]
 do_new_mount+0x302/0xa10 fs/namespace.c:3712
 do_mount fs/namespace.c:4035 [inline]
 __do_sys_mount fs/namespace.c:4224 [inline]
 __se_sys_mount+0x313/0x410 fs/namespace.c:4201
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5743:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2540 [inline]
 slab_free mm/slub.c:6663 [inline]
 kfree+0x1c0/0x660 mm/slub.c:6871
 free_sbd fs/gfs2/ops_fstype.c:72 [inline]
 gfs2_fill_super+0x14ef/0x21b0 fs/gfs2/ops_fstype.c:1316
 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691
 gfs2_get_tree+0x51/0x1e0 fs/gfs2/ops_fstype.c:1332
 vfs_get_tree+0x92/0x2a0 fs/super.c:1751
 fc_mount fs/namespace.c:1199 [inline]
 do_new_mount_fc fs/namespace.c:3636 [inline]
 do_new_mount+0x302/0xa10 fs/namespace.c:3712
 do_mount fs/namespace.c:4035 [inline]
 __do_sys_mount fs/namespace.c:4224 [inline]
 __se_sys_mount+0x313/0x410 fs/namespace.c:4201
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888012448000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 2920 bytes inside of
 freed 8192-byte region [ffff888012448000, ffff88801244a000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12448
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a442280 ffffea0000456000 dead000000000002
raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a442280 ffffea0000456000 dead000000000002
head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0000491201 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5441, tgid 5441 (syz-executor), ts 131440682441, free_ts 125215198586
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x234/0x290 mm/page_alloc.c:1846
 prep_new_page mm/page_alloc.c:1854 [inline]
 get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
 alloc_slab_page mm/slub.c:3075 [inline]
 allocate_slab+0x86/0x3b0 mm/slub.c:3248
 new_slab mm/slub.c:3302 [inline]
 ___slab_alloc+0xf2b/0x1960 mm/slub.c:4651
 __slab_alloc+0x65/0x100 mm/slub.c:4774
 __slab_alloc_node mm/slub.c:4850 [inline]
 slab_alloc_node mm/slub.c:5246 [inline]
 __do_kmalloc_node mm/slub.c:5651 [inline]
 __kmalloc_noprof+0x47d/0x800 mm/slub.c:5664
 kmalloc_noprof include/linux/slab.h:961 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 ops_init+0x7b/0x5c0 net/core/net_namespace.c:127
 setup_net+0x110/0x330 net/core/net_namespace.c:446
 copy_net_ns+0x3e3/0x570 net/core/net_namespace.c:581
 create_new_namespaces+0x3e7/0x6a0 kernel/nsproxy.c:130
 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:226
 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3171
 __do_sys_unshare kernel/fork.c:3242 [inline]
 __se_sys_unshare kernel/fork.c:3240 [inline]
 __x64_sys_unshare+0x38/0x50 kernel/fork.c:3240
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
page last free pid 4568 tgid 4568 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2943
 __slab_free+0x21b/0x2a0 mm/slub.c:5999
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:349
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4948 [inline]
 slab_alloc_node mm/slub.c:5258 [inline]
 __do_kmalloc_node mm/slub.c:5651 [inline]
 __kvmalloc_node_noprof+0x57f/0x920 mm/slub.c:7129
 allocate_hook_entries_size net/netfilter/core.c:58 [inline]
 __nf_hook_entries_try_shrink+0x31b/0x6f0 net/netfilter/core.c:257
 __nf_unregister_net_hook+0x4cc/0x6f0 net/netfilter/core.c:517
 nf_unregister_net_hook net/netfilter/core.c:-1 [inline]
 nf_unregister_net_hooks+0xcb/0x140 net/netfilter/core.c:610
 ops_pre_exit_list net/core/net_namespace.c:161 [inline]
 ops_undo_list+0x187/0x990 net/core/net_namespace.c:234
 cleanup_net+0x4d8/0x7a0 net/core/net_namespace.c:696
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Memory state around the buggy address:
 ffff888012448a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888012448a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888012448b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                          ^
 ffff888012448b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888012448c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	cc                   	int3
   1:	41 0f b6 04 17       	movzbl (%r15,%rdx,1),%eax
   6:	84 c0                	test   %al,%al
   8:	0f 85 78 01 00 00    	jne    0x186
   e:	44 89 23             	mov    %r12d,(%rbx)
  11:	b0 01                	mov    $0x1,%al
  13:	e9 99 00 00 00       	jmp    0xb1
  18:	31 c0                	xor    %eax,%eax
  1a:	e9 92 00 00 00       	jmp    0xb1
  1f:	48 89 f8             	mov    %rdi,%rax
  22:	48 c1 e8 03          	shr    $0x3,%rax
  26:	80 3c 10 00          	cmpb   $0x0,(%rax,%rdx,1)
* 2a:	74 29                	je     0x55 <-- trapping instruction
  2c:	49 89 ff             	mov    %rdi,%r15
  2f:	48 89 74 24 08       	mov    %rsi,0x8(%rsp)
  34:	49 89 d4             	mov    %rdx,%r12
  37:	4c 89 04 24          	mov    %r8,(%rsp)
  3b:	4c 89 cb             	mov    %r9,%rbx
  3e:	e8                   	.byte 0xe8
  3f:	55                   	push   %rbp