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BUG: KASAN: slab-out-of-bounds in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline]
BUG: KASAN: slab-out-of-bounds in bitmap_ipmac_gc_test net/netfilter/ipset/ip_set_bitmap_ipmac.c:102 [inline]
BUG: KASAN: slab-out-of-bounds in bitmap_ipmac_gc+0x119/0x590 net/netfilter/ipset/ip_set_bitmap_gen.h:277
Read of size 8 at addr ffff8880993dc400 by task kworker/0:4/9931

CPU: 0 PID: 9931 Comm: kworker/0:4 Not tainted 5.5.0-rc6-next-20200116-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x197/0x210 lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
 __kasan_report.cold+0x1b/0x32 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:641
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192
 __kasan_check_read+0x11/0x20 mm/kasan/common.c:95
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline]
 bitmap_ipmac_gc_test net/netfilter/ipset/ip_set_bitmap_ipmac.c:102 [inline]
 bitmap_ipmac_gc+0x119/0x590 net/netfilter/ipset/ip_set_bitmap_gen.h:277
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x6c3/0x1790 kernel/time/timer.c:1786
 __do_softirq+0x262/0x98c kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x19b/0x1e0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:cpu_relax arch/x86/include/asm/processor.h:689 [inline]
RIP: 0010:mutex_spin_on_owner+0x247/0x330 kernel/locking/mutex.c:579
Code: c3 be 08 00 00 00 4c 89 e7 e8 05 40 5a 00 4c 89 e0 48 c1 e8 03 42 80 3c 38 00 0f 85 e1 00 00 00 49 8b 04 24 a8 01 75 96 f3 90 <e9> 2f fe ff ff 0f 0b e8 ed 5d 08 00 84 c0 0f 85 ff fd ff ff 48 c7
RSP: 0018:ffffc90002887a50 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffff88809ac5a340 RCX: 1ffffffff1367781
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000001
RBP: ffffc90002887a90 R08: 1ffff1100a97b4a0 R09: ffffed100a97b4a1
R10: ffffed100a97b4a0 R11: ffff888054bda507 R12: ffffffff8a747960
R13: ffff888054bda500 R14: 0000000000000000 R15: dffffc0000000000
 mutex_optimistic_spin kernel/locking/mutex.c:673 [inline]
 __mutex_lock_common kernel/locking/mutex.c:959 [inline]
 __mutex_lock+0x32b/0x13c0 kernel/locking/mutex.c:1103
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72
 addrconf_dad_work+0xad/0x11d0 net/ipv6/addrconf.c:4033
 process_one_work+0xa05/0x17a0 kernel/workqueue.c:2264
 worker_thread+0x98/0xe40 kernel/workqueue.c:2410
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Allocated by task 9962:
 save_stack+0x23/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 __kasan_kmalloc mm/kasan/common.c:515 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:488
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:529
 __do_kmalloc mm/slab.c:3656 [inline]
 __kmalloc+0x163/0x770 mm/slab.c:3665
 kmalloc include/linux/slab.h:560 [inline]
 kzalloc include/linux/slab.h:669 [inline]
 ip_set_alloc+0x38/0x5e net/netfilter/ipset/ip_set_core.c:255
 init_map_ipmac net/netfilter/ipset/ip_set_bitmap_ipmac.c:302 [inline]
 bitmap_ipmac_create+0x4e8/0xa00 net/netfilter/ipset/ip_set_bitmap_ipmac.c:365
 ip_set_create+0x6f1/0x1500 net/netfilter/ipset/ip_set_core.c:1111
 nfnetlink_rcv_msg+0xcf2/0xfb0 net/netfilter/nfnetlink.c:229
 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
 nfnetlink_rcv+0x1ba/0x460 net/netfilter/nfnetlink.c:563
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:672
 ____sys_sendmsg+0x753/0x880 net/socket.c:2343
 ___sys_sendmsg+0x100/0x170 net/socket.c:2397
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430
 __do_sys_sendmsg net/socket.c:2439 [inline]
 __se_sys_sendmsg net/socket.c:2437 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 9741:
 save_stack+0x23/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 kasan_set_free_info mm/kasan/common.c:337 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:476
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:485
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x10a/0x2c0 mm/slab.c:3757
 security_cred_free+0xa9/0x110 security/security.c:1581
 put_cred_rcu+0x129/0x4b0 kernel/cred.c:114
 __put_cred+0x1ef/0x270 kernel/cred.c:148
 put_cred include/linux/cred.h:287 [inline]
 do_faccessat+0x693/0x7f0 fs/open.c:439
 __do_sys_access fs/open.c:450 [inline]
 __se_sys_access fs/open.c:448 [inline]
 __x64_sys_access+0x59/0x80 fs/open.c:448
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8880993dc400
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes inside of
 32-byte region [ffff8880993dc400, ffff8880993dc420)
The buggy address belongs to the page:
page:ffffea000264f700 refcount:1 mapcount:0 mapping:ffff8880aa4001c0 index:0xffff8880993dcfc1
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea0002a41a48 ffffea00029f6308 ffff8880aa4001c0
raw: ffff8880993dcfc1 ffff8880993dc000 000000010000003f 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880993dc300: fb fb fb fb fc fc fc fc 00 00 05 fc fc fc fc fc
 ffff8880993dc380: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
>ffff8880993dc400: 04 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc
                   ^
 ffff8880993dc480: 00 01 fc fc fc fc fc fc fb fb fb fb fc fc fc fc
 ffff8880993dc500: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
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