syzbot

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WARNING: CPU: 1 PID: 17521 at mm/shmem.c:1420 shmem_evict_inode+0x8ee/0xbe0 mm/shmem.c:1420
Modules linked in:
CPU: 1 UID: 0 PID: 17521 Comm: syz.4.3375 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
RIP: 0010:shmem_evict_inode+0x8ee/0xbe0 mm/shmem.c:1420
Code: fe e8 e6 4e be ff 45 85 ff 75 ac e8 9c 53 be ff 48 8b 74 24 28 48 8b 7c 24 30 e8 3d d8 96 ff e9 e5 fd ff ff e8 83 53 be ff 90 <0f> 0b 90 e9 51 f9 ff ff e8 75 53 be ff 4c 89 e2 48 b8 00 00 00 00
RSP: 0018:ffffc9000cfdf7d0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88805f4d5cf0 RCX: ffffffff81fcae6e
RDX: ffff8880246a2440 RSI: ffffffff81fcb51d RDI: 0000000000000007
RBP: ffffc9000cfdf8f8 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000000 R12: 0000000000000008
R13: 0000000000000000 R14: ffffed100be9ab9a R15: 1ffff1100be9ab7c
FS:  0000000000000000(0000) GS:ffff8880975c3000(0000) knlGS:0000000000000000
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f7416288 CR3: 000000006696a000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 evict+0x3e6/0x920 fs/inode.c:810
 iput_final fs/inode.c:1897 [inline]
 iput fs/inode.c:1923 [inline]
 iput+0x521/0x880 fs/inode.c:1909
 dentry_unlink_inode+0x29c/0x480 fs/dcache.c:466
 __dentry_kill+0x1d0/0x600 fs/dcache.c:669
 dput.part.0+0x4b1/0x9b0 fs/dcache.c:911
 dput+0x1f/0x30 fs/dcache.c:901
 __fput+0x51c/0xb70 fs/file_table.c:476
 task_work_run+0x14d/0x240 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x86f/0x2bf0 kernel/exit.c:961
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1102
 get_signal+0x2673/0x26d0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x8f/0x790 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:40 [inline]
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 irqentry_exit_to_user_mode+0x12a/0x270 kernel/entry/common.c:73
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0023:0xf70de579
Code: Unable to access opcode bytes at 0xf70de54f.
RSP: 002b:00000000f54ce55c EFLAGS: 00010296
RAX: 000000000000000b RBX: 0000000000000004 RCX: 00000000f70de579
RDX: 0000000000000651 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>