general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 PID: 1108 Comm: syz.2.151 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:2952 [inline]
RIP: 0010:update_sit_entry_for_alloc fs/f2fs/segment.c:2396 [inline]
RIP: 0010:update_sit_entry+0x4f9/0x15a0 fs/f2fs/segment.c:2440
Code: 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 7e e3 8c ff 48 8b 1b 4c 01 f3 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 0f 85 55 0f 00 00 44 0f b6 23 44 89 e0 44 08 f8
RSP: 0018:ffffc90002386d00 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: dffffc0000000000
RDX: ffff88811c5f9440 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90002386dd0 R08: ffff88811c5f9440 R09: 0000000000000003
R10: 00000000ffffffff R11: 0000000000000000 R12: 0000000000000000
R13: ffff88811dfb40c8 R14: 0000000000000000 R15: 0000000000000004
FS:  00007f07384836c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0738482f98 CR3: 0000000108d79000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 f2fs_allocate_data_block+0x148c/0x3af0 fs/f2fs/segment.c:3430
 do_write_page+0x297/0xc40 fs/f2fs/segment.c:3532
 f2fs_outplace_write_data+0x14f/0x2d0 fs/f2fs/segment.c:3605
 f2fs_do_writ
----------------
Code disassembly (best guess), 4 bytes skipped:
   0:	df 80 3c 08 00 74    	filds  0x7400083c(%rax)
   6:	08 48 89             	or     %cl,-0x77(%rax)
   9:	df e8                	fucomip %st(0),%st
   b:	7e e3                	jle    0xfffffff0
   d:	8c ff                	mov    %?,%edi
   f:	48 8b 1b             	mov    (%rbx),%rbx
  12:	4c 01 f3             	add    %r14,%rbx
  15:	48 89 d8             	mov    %rbx,%rax
  18:	48 c1 e8 03          	shr    $0x3,%rax
  1c:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  23:	fc ff df
* 26:	0f b6 04 08          	movzbl (%rax,%rcx,1),%eax <-- trapping instruction
  2a:	84 c0                	test   %al,%al
  2c:	0f 85 55 0f 00 00    	jne    0xf87
  32:	44 0f b6 23          	movzbl (%rbx),%r12d
  36:	44 89 e0             	mov    %r12d,%eax
  39:	44 08 f8             	or     %r15b,%al