usercopy: kernel memory overwrite attempt detected to 000000004fd47519 (kmalloc-1024) (984 bytes)
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kernel BUG at mm/usercopy.c:72!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 30730 Comm: syz-executor2 Not tainted 4.15.0-rc2+ #144
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: 00000000401de85a task.stack: 000000006ad720fe
RIP: 0010:report_usercopy mm/usercopy.c:64 [inline]
RIP: 0010:__check_object_size+0x3a2/0x4f0 mm/usercopy.c:264
RSP: 0018:ffff8801c96e7c60 EFLAGS: 00010286
RAX: 0000000000000061 RBX: ffffffff85328580 RCX: 0000000000000000
RDX: 0000000000000061 RSI: ffffc900047de000 RDI: ffffed00392dcf80
RBP: ffff8801c96e7d50 R08: 1ffffffff0d2ab1f R09: 0000000000000000
R10: 000000004047ad4f R11: 0000000000000000 R12: ffffffff85328540
R13: ffff8801d407d710 R14: 00000000000003d8 R15: ffffea0007501f00
FS:  00007fcd7d8ab700(0000) GS:ffff8801db500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe1ead1eb0 CR3: 00000001d1022000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 check_object_size include/linux/thread_info.h:112 [inline]
 check_copy_size include/linux/thread_info.h:143 [inline]
 copy_from_user include/linux/uaccess.h:146 [inline]
 memdup_user+0x46/0x90 mm/util.c:168
 ioctl_file_dedupe_range fs/ioctl.c:597 [inline]
 do_vfs_ioctl+0x53e/0x1530 fs/ioctl.c:680
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x452a39
RSP: 002b:00007fcd7d8aac58 EFLAGS: 00000212 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000007580d8 RCX: 0000000000452a39
RDX: 00000000206a9fe0 RSI: 00000000c0189436 RDI: 0000000000000017
RBP: 000000000000039b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f2728
R13: 00000000ffffffff R14: 00007fcd7d8ab6d4 R15: 0000000000000005
Code: 48 0f 44 da e8 c0 6f c2 ff 48 8b 85 28 ff ff ff 4d 89 f1 4c 89 e9 4c 89 e2 48 89 de 48 c7 c7 40 86 32 85 49 89 c0 e8 b3 2d ac ff <0f> 0b 48 c7 c0 00 84 32 85 eb 96 48 c7 c0 40 84 32 85 eb 8d 48 
RIP: report_usercopy mm/usercopy.c:64 [inline] RSP: ffff8801c96e7c60
RIP: __check_object_size+0x3a2/0x4f0 mm/usercopy.c:264 RSP: ffff8801c96e7c60
---[ end trace 6515e030b769ca0f ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..