==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: null-ptr-deref in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
BUG: KASAN: null-ptr-deref in page_ref_count include/linux/page_ref.h:67 [inline]
BUG: KASAN: null-ptr-deref in put_page_testzero include/linux/mm.h:1033 [inline]
BUG: KASAN: null-ptr-deref in folio_put_testzero include/linux/mm.h:1039 [inline]
BUG: KASAN: null-ptr-deref in folio_put include/linux/mm.h:1466 [inline]
BUG: KASAN: null-ptr-deref in filemap_fault+0x544/0x24a0 mm/filemap.c:3380
Read of size 4 at addr 0000000000000032 by task syz-executor.1/15650

CPU: 0 PID: 15650 Comm: syz-executor.1 Not tainted 6.3.0-rc4-next-20230331-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 print_report mm/kasan/report.c:465 [inline]
 kasan_report+0xec/0x130 mm/kasan/report.c:572
 check_region_inline mm/kasan/generic.c:181 [inline]
 kasan_check_range+0x141/0x190 mm/kasan/generic.c:187
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
 page_ref_count include/linux/page_ref.h:67 [inline]
 put_page_testzero include/linux/mm.h:1033 [inline]
 folio_put_testzero include/linux/mm.h:1039 [inline]
 folio_put include/linux/mm.h:1466 [inline]
 filemap_fault+0x544/0x24a0 mm/filemap.c:3380
 __do_fault+0x107/0x600 mm/memory.c:4177
 do_read_fault mm/memory.c:4531 [inline]
 do_fault mm/memory.c:4660 [inline]
 do_pte_missing mm/memory.c:3648 [inline]
 handle_pte_fault mm/memory.c:4948 [inline]
 __handle_mm_fault+0x2806/0x4180 mm/memory.c:5090
 handle_mm_fault+0x2c0/0x9c0 mm/memory.c:5236
 do_user_addr_fault+0x53d/0x1240 arch/x86/mm/fault.c:1462
 handle_page_fault arch/x86/mm/fault.c:1556 [inline]
 exc_page_fault+0x98/0x170 arch/x86/mm/fault.c:1612
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0010:copy_user_short_string+0xa/0x40 arch/x86/lib/copy_user_64.S:232
Code: 83 f8 12 74 0a 89 d1 f3 a4 89 c8 0f 01 ca c3 89 d0 0f 01 ca c3 01 ca eb e7 0f 1f 80 00 00 00 00 89 d1 83 e2 07 c1 e9 03 74 12 <4c> 8b 06 4c 89 07 48 8d 76 08 48 8d 7f 08 ff c9 75 ee 21 d2 74 10
RSP: 0018:ffffc900059dfa00 EFLAGS: 00050202
RAX: 0000000000000001 RBX: 0000000000000038 RCX: 0000000000000007
RDX: 0000000000000000 RSI: 000000002000a000 RDI: ffffc900059dfa50
RBP: ffffc900059dfa50 R08: 0000000000000001 R09: ffffc900059dfa87
R10: fffff52000b3bf50 R11: 0000000000000000 R12: 00007fffffffefc8
R13: 000000002000a000 R14: 0000000000000000 R15: ffffc900059dfb38
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline]
 _copy_from_user+0x147/0x180 lib/usercopy.c:23
 copy_from_user include/linux/uaccess.h:183 [inline]
 copy_msghdr_from_user+0x89/0x150 net/socket.c:2432
 sendmsg_copy_msghdr net/socket.c:2532 [inline]
 ___sys_sendmsg+0xdd/0x1b0 net/socket.c:2551
 __sys_sendmmsg+0x18f/0x460 net/socket.c:2641
 __do_sys_sendmmsg net/socket.c:2670 [inline]
 __se_sys_sendmmsg net/socket.c:2667 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2667
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f388248c0f9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3883160168 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f38825ac120 RCX: 00007f388248c0f9
RDX: 040000000000035c RSI: 0000000020001700 RDI: 0000000000000009
RBP: 00007f38824e7b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffeb479d36f R14: 00007f3883160300 R15: 0000000000022000
 </TASK>
==================================================================
----------------
Code disassembly (best guess):
   0:	83 f8 12             	cmp    $0x12,%eax
   3:	74 0a                	je     0xf
   5:	89 d1                	mov    %edx,%ecx
   7:	f3 a4                	rep movsb %ds:(%rsi),%es:(%rdi)
   9:	89 c8                	mov    %ecx,%eax
   b:	0f 01 ca             	clac
   e:	c3                   	retq
   f:	89 d0                	mov    %edx,%eax
  11:	0f 01 ca             	clac
  14:	c3                   	retq
  15:	01 ca                	add    %ecx,%edx
  17:	eb e7                	jmp    0x0
  19:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  20:	89 d1                	mov    %edx,%ecx
  22:	83 e2 07             	and    $0x7,%edx
  25:	c1 e9 03             	shr    $0x3,%ecx
  28:	74 12                	je     0x3c
* 2a:	4c 8b 06             	mov    (%rsi),%r8 <-- trapping instruction
  2d:	4c 89 07             	mov    %r8,(%rdi)
  30:	48 8d 76 08          	lea    0x8(%rsi),%rsi
  34:	48 8d 7f 08          	lea    0x8(%rdi),%rdi
  38:	ff c9                	dec    %ecx
  3a:	75 ee                	jne    0x2a
  3c:	21 d2                	and    %edx,%edx
  3e:	74 10                	je     0x50