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BUG: KASAN: slab-out-of-bounds in nla_strlcpy+0x13d/0x150 lib/nlattr.c:314
Read of size 1 at addr ffff8801c04c356d by task syz-executor1/25811

CPU: 1 PID: 25811 Comm: syz-executor1 Not tainted 4.17.0-rc7+ #74
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+0x1b9/0x294 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430
 nla_strlcpy+0x13d/0x150 lib/nlattr.c:314
 nfnl_acct_new+0x574/0xc50 net/netfilter/nfnetlink_acct.c:118
 nfnetlink_rcv_msg+0xdb5/0xff0 net/netfilter/nfnetlink.c:212
 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2448
 nfnetlink_rcv+0x1fe/0x1ba0 net/netfilter/nfnetlink.c:513
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x58b/0x740 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x9f0/0xfa0 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:639
 sock_write_iter+0x35a/0x5a0 net/socket.c:908
 call_write_iter include/linux/fs.h:1784 [inline]
 new_sync_write fs/read_write.c:474 [inline]
 __vfs_write+0x64d/0x960 fs/read_write.c:487
 vfs_write+0x1f8/0x560 fs/read_write.c:549
 ksys_write+0xf9/0x250 fs/read_write.c:598
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:607
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455a09
RSP: 002b:00007f307a00bc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f307a00c6d4 RCX: 0000000000455a09
RDX: 000000000000001f RSI: 0000000020000040 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000007a8 R14: 0000000000700860 R15: 0000000000000000

Allocated by task 25770:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490
 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3554
 ptlock_alloc+0x20/0x80 mm/memory.c:4712
 ptlock_init include/linux/mm.h:1809 [inline]
 pgtable_page_ctor include/linux/mm.h:1843 [inline]
 pte_alloc_one+0x6b/0x120 arch/x86/mm/pgtable.c:33
 do_fault_around mm/memory.c:3586 [inline]
 do_read_fault mm/memory.c:3627 [inline]
 do_fault mm/memory.c:3732 [inline]
 handle_pte_fault mm/memory.c:3963 [inline]
 __handle_mm_fault+0x3686/0x4310 mm/memory.c:4087
 handle_mm_fault+0x53a/0xc70 mm/memory.c:4124
 __do_page_fault+0x60b/0xe40 arch/x86/mm/fault.c:1399
 do_page_fault+0xee/0x8a7 arch/x86/mm/fault.c:1474
 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1160

Freed by task 25770:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kmem_cache_free+0x86/0x2d0 mm/slab.c:3756
 ptlock_free+0x38/0x42 mm/memory.c:4721
 pte_lock_deinit include/linux/mm.h:1819 [inline]
 pgtable_page_dtor include/linux/mm.h:1851 [inline]
 ___pte_free_tlb+0x52/0xc0 arch/x86/mm/pgtable.c:59
 __pte_free_tlb arch/x86/include/asm/pgalloc.h:73 [inline]
 free_pte_range mm/memory.c:446 [inline]
 free_pmd_range mm/memory.c:464 [inline]
 free_pud_range mm/memory.c:498 [inline]
 free_p4d_range mm/memory.c:532 [inline]
 free_pgd_range+0xc1d/0xf30 mm/memory.c:612
 free_pgtables+0x2c3/0x380 mm/memory.c:644
 exit_mmap+0x2c9/0x5a0 mm/mmap.c:3106
 __mmput kernel/fork.c:961 [inline]
 mmput+0x251/0x610 kernel/fork.c:982
 exit_mm kernel/exit.c:544 [inline]
 do_exit+0xe98/0x2730 kernel/exit.c:852
 do_group_exit+0x16f/0x430 kernel/exit.c:968
 __do_sys_exit_group kernel/exit.c:979 [inline]
 __se_sys_exit_group kernel/exit.c:977 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:977
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801c04c3528
 which belongs to the cache page->ptl of size 56
The buggy address is located 13 bytes to the right of
 56-byte region [ffff8801c04c3528, ffff8801c04c3560)
The buggy address belongs to the page:
page:ffffea00070130c0 count:1 mapcount:0 mapping:ffff8801c04c3000 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801c04c3000 0000000000000000 000000010000002e
raw: ffffea00074f1c20 ffffea00075ed420 ffff8801da810040 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c04c3400: fc fc fc fc fb fb fb fb fb fb fb fc fc fc fc fb
 ffff8801c04c3480: fb fb fb fb fb fb fc fc fc fc fb fb fb fb fb fb
>ffff8801c04c3500: fb fc fc fc fc fb fb fb fb fb fb fb fc fc fc fc
                                                          ^
 ffff8801c04c3580: fb fb fb fb fb fb fb fc fc fc fc fb fb fb fb fb
 ffff8801c04c3600: fb fb fc fc fc fc fb fb fb fb fb fb fb fc fc fc
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