syzbot

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memcpy: detected field-spanning write (size 93) of single field "&fh->fb" at fs/overlayfs/export.c:799 (size 21)
WARNING: CPU: 0 PID: 3609 at fs/overlayfs/export.c:799 ovl_fid_to_fh fs/overlayfs/export.c:799 [inline]
WARNING: CPU: 0 PID: 3609 at fs/overlayfs/export.c:799 ovl_fh_to_dentry+0x880/0x950 fs/overlayfs/export.c:812
Modules linked in:
CPU: 0 PID: 3609 Comm: syz-executor307 Not tainted 6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
RIP: 0010:ovl_fid_to_fh fs/overlayfs/export.c:799 [inline]
RIP: 0010:ovl_fh_to_dentry+0x880/0x950 fs/overlayfs/export.c:812
Code: f9 ff ff e8 c2 0f ab fe b9 15 00 00 00 4c 89 f6 48 c7 c2 e0 26 28 8a 48 c7 c7 40 27 28 8a c6 05 77 db fa 0a 01 e8 0c 31 78 06 <0f> 0b e9 ec f8 ff ff 49 c7 c6 ea ff ff ff bb ea ff ff ff c7 44 24
RSP: 0018:ffffc90003e6fb30 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000060 RCX: 0000000000000000
RDX: ffff88801e5e57c0 RSI: ffffffff81621b98 RDI: fffff520007cdf58
RBP: ffff88807f4a4180 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 203a7970636d656d R12: 00000000000000fb
R13: 1ffff920007cdf6e R14: 000000000000005d R15: ffff88807f4a4183
FS:  00005555565eb300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005632055db6f8 CR3: 00000000204b2000 CR4: 0000000000350ee0
Call Trace:
 <TASK>
 exportfs_decode_fh_raw+0x127/0x7d0 fs/exportfs/expfs.c:435
 exportfs_decode_fh+0x38/0x90 fs/exportfs/expfs.c:575
 do_handle_to_path fs/fhandle.c:152 [inline]
 handle_to_path fs/fhandle.c:207 [inline]
 do_handle_open+0x2b6/0x8b0 fs/fhandle.c:223
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f27eed2fcc9
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffc2b58678 EFLAGS: 00000246 ORIG_RAX: 0000000000000130
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f27eed2fcc9
RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 00007f27eecf3e70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f27eecf3f00
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>