F2FS-fs (loop4): Mounted with checkpoint version = 48b305e6 general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] CPU: 1 PID: 773 Comm: syz.4.90 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:2958 [inline] RIP: 0010:update_sit_entry_for_alloc fs/f2fs/segment.c:2398 [inline] RIP: 0010:update_sit_entry+0x4f9/0x15a0 fs/f2fs/segment.c:2442 Code: 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 5e eb 8a 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:ffffc900016771c0 EFLAGS: 00010206 RAX: 0000000000000005 RBX: 000000000000002b RCX: dffffc0000000000 RDX: ffff88811bbf1440 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90001677290 R08: ffff88811bbf1440 R09: 0000000000000003 R10: 00000000ffffffff R11: 0000000000000000 R12: 0000000000000000 R13: ffff8881093200c8 R14: 000000000000002b R15: 0000000000000020 FS: 00007f499963a6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4999619d58 CR3: 0000000123558000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: f2fs_allocate_data_block+0x14b8/0x3b00 fs/f2fs/segment.c:3432 __allocate_data_block fs/f2fs/data.c:1488 [inline] f2fs_map_blocks+0x126e/0x3ba0 fs/f2fs/data.c:1671 f2fs_expand_inode_data+0x6c8/0xb00 fs/f2fs/file.c:1852 f2fs_fallocate+0x3cc/0x720 fs/f2fs/file.c:1953 vfs_fallocate+0x4c5/0x5a0 fs/open.c:324 ioctl_preallocate fs/ioctl.c:290 [inline] file_ioctl fs/ioctl.c:330 [inline] do_vfs_ioctl+0x194b/0x1cd0 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:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f499879c799 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:00007f499963a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f4998a15fa0 RCX: 00007f499879c799 RDX: 00002000000000c0 RSI: 0000000040305828 RDI: 0000000000000004 RBP: 00007f4998832bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4998a16038 R14: 00007f4998a15fa0 R15: 00007fffafcc9908 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:2958 [inline] RIP: 0010:update_sit_entry_for_alloc fs/f2fs/segment.c:2398 [inline] RIP: 0010:update_sit_entry+0x4f9/0x15a0 fs/f2fs/segment.c:2442 Code: 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 5e eb 8a 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:ffffc900016771c0 EFLAGS: 00010206 RAX: 0000000000000005 RBX: 000000000000002b RCX: dffffc0000000000 RDX: ffff88811bbf1440 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90001677290 R08: ffff88811bbf1440 R09: 0000000000000003 R10: 00000000ffffffff R11: 0000000000000000 R12: 0000000000000000 R13: ffff8881093200c8 R14: 000000000000002b R15: 0000000000000020 FS: 00007f499963a6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f862ba6f000 CR3: 0000000123558000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: fc cld 3: ff lcall (bad) 4: df 80 3c 08 00 74 filds 0x7400083c(%rax) a: 08 48 89 or %cl,-0x77(%rax) d: df e8 fucomip %st(0),%st f: 5e pop %rsi 10: eb 8a jmp 0xffffff9c 12: ff 48 8b decl -0x75(%rax) 15: 1b 4c 01 f3 sbb -0xd(%rcx,%rax,1),%ecx 19: 48 89 d8 mov %rbx,%rax 1c: 48 c1 e8 03 shr $0x3,%rax 20: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 27: fc ff df * 2a: 0f b6 04 08 movzbl (%rax,%rcx,1),%eax <-- trapping instruction 2e: 84 c0 test %al,%al 30: 0f 85 55 0f 00 00 jne 0xf8b 36: 44 0f b6 23 movzbl (%rbx),%r12d 3a: 44 89 e0 mov %r12d,%eax 3d: 44 08 f8 or %r15b,%al