general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 0 PID: 525 Comm: syz.2.18 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:2947 [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 3e 09 8d 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:ffffc90000f371e0 EFLAGS: 00010203 RAX: 0000000000000001 RBX: 000000000000000c RCX: dffffc0000000000 RDX: ffff888120b59440 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000f372b0 R08: ffff888120b59440 R09: 0000000000000003 R10: 00000000ffffffff R11: 0000000000000000 R12: 0000000000000000 R13: ffff8881201e00c8 R14: 000000000000000c R15: 0000000000000004 FS: 00007f1a7d6786c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f067a091000 CR3: 000000011f2ee000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: f2fs_allocate_data_block+0x148c/0x3af0 fs/f2fs/segment.c:3430 __allocate_data_block fs/f2fs/data.c:1488 [inline] f2fs_map_blocks+0x11a8/0x3a60 fs/f2fs/data.c:1671 f2fs_expand_inode_data+0x639/0xa70 fs/f2fs/file.c:1847 f2fs_fallocate+0x3cc/0x720 fs/f2fs/file.c:1948 vfs_fallocate+0x4c5/0x5a0 fs/open.c:324 ioctl_preallocate fs/ioctl.c:290 [inline] file_ioctl fs/ioctl.c:-1 [inline] do_vfs_ioctl+0x1a1d/0x1c80 fs/ioctl.c:849 __do_sys_ioctl fs/ioctl.c:868 [inline] __se_sys_ioctl+0x9f/0x1b0 fs/ioctl.c:856 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f1a7c78e969 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f1a7d678038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f1a7c9b5fa0 RCX: 00007f1a7c78e969 RDX: 00002000000000c0 RSI: 0000000040305828 RDI: 0000000000000004 RBP: 00007f1a7c810ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1a7c9b5fa0 R15: 00007ffc47bfd038 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:2947 [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 3e 09 8d 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:ffffc90000f371e0 EFLAGS: 00010203 RAX: 0000000000000001 RBX: 000000000000000c RCX: dffffc0000000000 RDX: ffff888120b59440 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000f372b0 R08: ffff888120b59440 R09: 0000000000000003 R10: 00000000ffffffff R11: 0000000000000000 R12: 0000000000000000 R13: ffff8881201e00c8 R14: 000000000000000c R15: 0000000000000004 FS: 00007f1a7d6786c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2613e27000 CR3: 000000011f2ee000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- 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: 3e 09 8d ff 48 8b 1b ds or %ecx,0x1b8b48ff(%rbp) 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