------------[ cut here ]------------
WARNING: CPU: 1 PID: 4379 at fs/iomap/buffered-io.c:975 iomap_page_mkwrite_iter fs/iomap/buffered-io.c:975 [inline]
WARNING: CPU: 1 PID: 4379 at fs/iomap/buffered-io.c:975 iomap_page_mkwrite+0x54e/0x690 fs/iomap/buffered-io.c:998
Modules linked in:
CPU: 1 PID: 4379 Comm: syz.4.16 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:iomap_page_mkwrite_iter fs/iomap/buffered-io.c:975 [inline]
RIP: 0010:iomap_page_mkwrite+0x54e/0x690 fs/iomap/buffered-io.c:998
Code: 80 3c 08 00 74 08 4c 89 f7 e8 ee c1 d8 ff 4d 8b 36 4c 89 f6 48 83 e6 04 31 ff e8 ad c1 93 ff 49 83 e6 04 75 3e e8 c2 bd 93 ff <0f> 0b eb 3a 48 89 df 4c 89 f6 44 89 e2 31 c9 4c 8b 44 24 18 e8 f9
RSP: 0018:ffffc9000347f220 EFLAGS: 00010287
RAX: ffffffff81e5528e RBX: ffffea0001723b80 RCX: 0000000000080000
RDX: ffffc9000ef5b000 RSI: 0000000000002f38 RDI: 0000000000002f39
RBP: ffffc9000347f3d0 R08: ffffea0001723b87 R09: 1ffffd40002e4770
R10: dffffc0000000000 R11: fffff940002e4771 R12: 0000000000001000
R13: 1ffff9200068fe4c R14: 0000000000000000 R15: ffffc9000347f280
FS:  00007fc4f247a6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffed2322f04 CR3: 000000002a52e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __xfs_filemap_fault+0x353/0x8f0 fs/xfs/xfs_file.c:1346
 do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922
 wp_page_shared+0x16b/0x6d0 mm/memory.c:3259
 handle_pte_fault mm/memory.c:4668 [inline]
 __handle_mm_fault mm/memory.c:4785 [inline]
 handle_mm_fault+0x1f06/0x4410 mm/memory.c:4883
 do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1357
 handle_page_fault arch/x86/mm/fault.c:1445 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0010:copy_user_enhanced_fast_string+0xe/0x40 arch/x86/lib/copy_user_64.S:206
Code: 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 90 90 90 90 90 90 90 0f 01 cb 83 fa 40 0f 82 70 ff ff ff 89 d1 <f3> a4 31 c0 0f 01 ca c3 90 90 90 90 90 90 90 90 90 90 89 d1 83 f8
RSP: 0018:ffffc9000347f8a0 EFLAGS: 00050206
RAX: ffffffff83e1d001 RBX: 00002000000000ff RCX: 00000000000000ea
RDX: 00000000000000ea RSI: ffff88805c8ee000 RDI: 0000200000000040
RBP: 00000000000000ea R08: ffff88805c8ee0e9 R09: 1ffff1100b91dc1d
R10: dffffc0000000000 R11: ffffed100b91dc1e R12: ffff88805c8ee000
R13: 00000000000000ea R14: 00007ffffffff000 R15: 000020000000012a
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline]
 copyout lib/iov_iter.c:157 [inline]
 copy_page_to_iter_iovec lib/iov_iter.c:228 [inline]
 __copy_page_to_iter lib/iov_iter.c:861 [inline]
 copy_page_to_iter+0x49e/0x910 lib/iov_iter.c:889
 filemap_read+0x1e2d/0x2540 mm/filemap.c:2698
 xfs_file_buffered_read+0x182/0x300 fs/xfs/xfs_file.c:302
 xfs_file_read_iter+0x276/0x500 fs/xfs/xfs_file.c:327
 call_read_iter include/linux/fs.h:2167 [inline]
 new_sync_read fs/read_write.c:404 [inline]
 vfs_read+0x759/0xd60 fs/read_write.c:485
 ksys_read+0x152/0x260 fs/read_write.c:623
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc4f423fcb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc4f247a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fc4f44bb090 RCX: 00007fc4f423fcb9
RDX: 00000000000000ea RSI: 0000200000000040 RDI: 0000000000000004
RBP: 00007fc4f42adbf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc4f44bb128 R14: 00007fc4f44bb090 R15: 00007ffeeb540e48
 </TASK>
----------------
Code disassembly (best guess):
   0:	89 d1                	mov    %edx,%ecx
   2:	c1 e9 03             	shr    $0x3,%ecx
   5:	83 e2 07             	and    $0x7,%edx
   8:	f3 48 a5             	rep movsq %ds:(%rsi),%es:(%rdi)
   b:	89 d1                	mov    %edx,%ecx
   d:	f3 a4                	rep movsb %ds:(%rsi),%es:(%rdi)
   f:	31 c0                	xor    %eax,%eax
  11:	0f 01 ca             	clac
  14:	c3                   	ret
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	90                   	nop
  1c:	0f 01 cb             	stac
  1f:	83 fa 40             	cmp    $0x40,%edx
  22:	0f 82 70 ff ff ff    	jb     0xffffff98
  28:	89 d1                	mov    %edx,%ecx
* 2a:	f3 a4                	rep movsb %ds:(%rsi),%es:(%rdi) <-- trapping instruction
  2c:	31 c0                	xor    %eax,%eax
  2e:	0f 01 ca             	clac
  31:	c3                   	ret
  32:	90                   	nop
  33:	90                   	nop
  34:	90                   	nop
  35:	90                   	nop
  36:	90                   	nop
  37:	90                   	nop
  38:	90                   	nop
  39:	90                   	nop
  3a:	90                   	nop
  3b:	90                   	nop
  3c:	89 d1                	mov    %edx,%ecx
  3e:	83                   	.byte 0x83
  3f:	f8                   	clc