audit: type=1400 audit(1542453762.972:15): avc:  denied  { write } for  pid=5271 comm="syz-executor2" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_netfilter_socket permissive=1
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kernel BUG at fs/ext4/inode.c:2462!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 5277 Comm: syz-executor0 Not tainted 4.4.163+ #122
task: ffff8801d63cdf00 task.stack: ffff8801c1448000
RIP: 0010:[<ffffffff81640120>]  [<ffffffff81640120>] mpage_prepare_extent_to_map+0x670/0x8e0 fs/ext4/inode.c:2462
RSP: 0018:ffff8801c144f5a0  EFLAGS: 00010212
RAX: 0000000000040000 RBX: ffffea000288fd00 RCX: ffffc90000d2b000
RDX: 0000000000037c5c RSI: ffffffff81640120 RDI: ffffea000288fd10
RBP: ffff8801c144f758 R08: ffff8801d63ce7c8 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000018 R14: dffffc0000000000 R15: ffff8801c144f8a0
FS:  00007f7aa7d5b700(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f521000 CR3: 00000001cf561000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 1ffff10038289ec2 ffff8801c144f630 ffff8801c144f8a8 ffff8801c144f8b0
 0000000081a38520 0007ffffffffffff ffff8801cecd5388 0000000e0000000c
 7fffffffffffffef ffff8801c144f670 ffff8801c144f8b8 ffffed0038289f15
Call Trace:
 [<ffffffff8164f37c>] ext4_writepages+0xd4c/0x2c20 fs/ext4/inode.c:2617
 [<ffffffff813d76ff>] do_writepages+0xef/0x1d0 mm/page-writeback.c:2334
 [<ffffffff813b90b9>] __filemap_fdatawrite_range+0x1a9/0x250 mm/filemap.c:347
 [<ffffffff813b91b3>] __filemap_fdatawrite mm/filemap.c:355 [inline]
 [<ffffffff813b91b3>] filemap_flush+0x23/0x30 mm/filemap.c:380
 [<ffffffff81646a18>] ext4_alloc_da_blocks+0x108/0x3c0 fs/ext4/inode.c:2993
 [<ffffffff8162ae7f>] ext4_release_file+0x1ff/0x2e0 fs/ext4/file.c:42
 [<ffffffff81496e35>] __fput+0x235/0x6f0 fs/file_table.c:208
 [<ffffffff81497375>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8112f23f>] task_work_run+0x10f/0x190 kernel/task_work.c:115
 [<ffffffff81101ab2>] get_signal+0x1182/0x14a0 kernel/signal.c:2151
 [<ffffffff8100bf65>] do_signal+0x95/0x1840 arch/x86/kernel/signal.c:712
 [<ffffffff81003eba>] exit_to_usermode_loop+0x11a/0x160 arch/x86/entry/common.c:250
 [<ffffffff81005924>] prepare_exit_to_usermode arch/x86/entry/common.c:287 [inline]
 [<ffffffff81005924>] syscall_return_slowpath+0x254/0x2d0 arch/x86/entry/common.c:352
 [<ffffffff8271256d>] int_ret_from_sys_call+0x25/0xa3
Code: 48 89 df e8 c3 44 d7 ff e9 32 ff ff ff e8 79 71 cc ff 48 89 df e8 51 5e d7 ff e9 fa fd ff ff e8 67 71 cc ff 0f 0b e8 60 71 cc ff <0f> 0b 31 c0 89 85 b0 fe ff ff e8 51 71 cc ff 8b 85 18 ff ff ff 
RIP  [<ffffffff81640120>] mpage_prepare_extent_to_map+0x670/0x8e0 fs/ext4/inode.c:2462
 RSP <ffff8801c144f5a0>
---[ end trace 8a11740fa5c4ec34 ]---