general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 0 PID: 4576 Comm: syz.1.1225 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:2946 [inline] RIP: 0010:update_sit_entry+0x5b4/0xf70 fs/f2fs/segment.c:2256 Code: 00 00 49 8d 5d 18 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 ea 73 90 ff 48 8b 1b 48 03 5d b0 48 89 d8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 a9 08 00 00 44 0f b6 33 44 89 f0 44 8b RSP: 0018:ffffc90000cc6bb8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888147c40000 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000cc6c38 R08: ffff888147c40000 R09: 0000000000000003 R10: 00000000ffffffff R11: 0000000000000002 R12: dffffc0000000000 R13: ffff8881167d6878 R14: 0000000000000000 R15: ffff888119a0c000 FS: 00007f57652256c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5765224ff8 CR3: 0000000117b4f000 CR4: 00000000003526b0 Call Trace: f2fs_allocate_data_block+0x15e8/0x3240 fs/f2fs/segment.c:3457 do_write_page+0x13c/0xab0 fs/f2fs/segment.c:3547 f2fs_outplace_write_data+0xf6/0x240 fs/f2fs/segment.c:3621 f2fs_do_write_data_page+0xf6a/0x1590 fs/f2fs/data.c:2733 f2fs_write_single_data_page+0xd19/0x1760 fs/f2fs/data.c:2832 f2fs_write_cache_pages fs/f2fs/data.c:3106 [inline] __f2fs_write_data_pages fs/f2fs/data.c:3256 [inline] f2fs_write_data_pages+0x17df/0x28e0 fs/f2fs/data.c:3283 do_writepages+0x473/0x6c0 mm/page-writeback.c:2388 filemap_fdatawrite_wbc+0x1f4/0x250 mm/filemap.c:409 __filemap_fdatawrite_range mm/filemap.c:442 [inline] __filemap_fdatawrite mm/filemap.c:448 [inline] filemap_fdatawrite+0xdc/0x140 mm/filemap.c:453 f2fs_sync_dirty_inodes+0x2ac/0x830 fs/f2fs/checkpoint.c:1116 block_operations fs/f2fs/checkpoint.c:1249 [inline] f2fs_write_checkpoint+0x9f5/0x1f50 fs/f2fs/checkpoint.c:1659 f2fs_issue_checkpoint+0x322/0x4e0 fs/f2fs/checkpoint.c:1866 f2fs_sync_fs+0x16f/0x2c0 fs/f2fs/super.c:1749 f2fs_mkdir+0x443/0x540 fs/f2fs/namei.c:727 vfs_mkdir+0x387/0x580 fs/namei.c:4073 do_mkdirat+0x171/0x4c0 fs/namei.c:4098 __do_sys_mkdirat fs/namei.c:4113 [inline] __se_sys_mkdirat fs/namei.c:4111 [inline] __x64_sys_mkdirat+0x89/0xa0 fs/namei.c:4111 x64_sys_call+0x37e/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:259 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: 0033:0x7f57667e8d97 Code: 00 66 90 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 db f7 ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 b8 02 01 00 00 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:00007f5765224e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f5765224ee0 RCX: 00007f57667e8d97 RDX: 00000000000001ff RSI: 0000200000000200 RDI: 00000000ffffff9c RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000200 R13: 00007f5765224ea0 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: ---[ end trace d23ce82a560025c4 ]--- RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:2946 [inline] RIP: 0010:update_sit_entry+0x5b4/0xf70 fs/f2fs/segment.c:2256 Code: 00 00 49 8d 5d 18 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 ea 73 90 ff 48 8b 1b 48 03 5d b0 48 89 d8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 a9 08 00 00 44 0f b6 33 44 89 f0 44 8b RSP: 0018:ffffc90000cc6bb8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888147c40000 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000cc6c38 R08: ffff888147c40000 R09: 0000000000000003 R10: 00000000ffffffff R11: 0000000000000002 R12: dffffc0000000000 R13: ffff8881167d6878 R14: 0000000000000000 R15: ffff888119a0c000 FS: 00007f57652256c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c317c67 CR3: 0000000117b4f000 CR4: 00000000003526a0 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 49 8d 5d 18 lea 0x18(%r13),%rbx 6: 48 89 d8 mov %rbx,%rax 9: 48 c1 e8 03 shr $0x3,%rax d: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) 12: 74 08 je 0x1c 14: 48 89 df mov %rbx,%rdi 17: e8 ea 73 90 ff call 0xff907406 1c: 48 8b 1b mov (%rbx),%rbx 1f: 48 03 5d b0 add -0x50(%rbp),%rbx 23: 48 89 d8 mov %rbx,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 0f b6 04 20 movzbl (%rax,%r12,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 0f 85 a9 08 00 00 jne 0x8e0 37: 44 0f b6 33 movzbl (%rbx),%r14d 3b: 44 89 f0 mov %r14d,%eax 3e: 44 rex.R 3f: 8b .byte 0x8b