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: 3128 Comm: syz.8.855 Tainted: G W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:3004 [inline] RIP: 0010:update_sit_entry_for_alloc fs/f2fs/segment.c:2399 [inline] RIP: 0010:update_sit_entry+0x4aa/0x1480 fs/f2fs/segment.c:2443 Code: 8b 45 d0 48 8d 58 18 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 f3 a8 8a ff 48 8b 1b 4c 01 fb 48 89 d8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 95 0e 00 00 44 0f b6 33 44 89 f0 44 08 RSP: 0018:ffffc90000a4e6e0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888141089440 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000a4e7b0 R08: ffff88811cbdc030 R09: 1ffff1102397b806 R10: dffffc0000000000 R11: ffffed102397b807 R12: 0000000000000002 R13: dffffc0000000000 R14: ffff888119c70000 R15: 0000000000000000 FS: 00007faecf7a16c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007faec5614000 CR3: 000000012790a000 CR4: 00000000003526a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: f2fs_allocate_data_block+0x146f/0x3ab0 fs/f2fs/segment.c:3434 do_write_page+0x277/0xb20 fs/f2fs/segment.c:3536 f2fs_outplace_write_data+0x14f/0x2e0 fs/f2fs/segment.c:3609 f2fs_convert_inline_page+0x78c/0xf50 fs/f2fs/inline.c:179 f2fs_convert_inline_inode+0x7bc/0x8b0 fs/f2fs/inline.c:232 f2fs_preallocate_blocks fs/f2fs/file.c:4753 [inline] f2fs_file_write_iter+0x12e9/0x27c0 fs/f2fs/file.c:4998 __kernel_write_iter+0x2a9/0x6a0 fs/read_write.c:517 __kernel_write+0x103/0x170 fs/read_write.c:537 __dump_emit+0x20d/0x310 fs/coredump.c:809 dump_emit+0xa8/0xc0 fs/coredump.c:846 writenote+0x1bd/0x2f0 fs/binfmt_elf.c:1530 write_note_info fs/binfmt_elf.c:1993 [inline] elf_core_dump+0x2786/0x30b0 fs/binfmt_elf.c:2341 do_coredump+0x160e/0x23a0 fs/coredump.c:760 get_signal+0x157d/0x1700 kernel/signal.c:2881 arch_do_signal_or_restart+0xd1/0x11c0 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x7a/0xb0 kernel/entry/common.c:174 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210 irqentry_exit_to_user_mode+0x9/0x10 kernel/entry/common.c:316 irqentry_exit+0x12/0x40 kernel/entry/common.c:419 exc_general_protection+0x14e/0x1e0 arch/x86/kernel/traps.c:729 asm_exc_general_protection+0x27/0x30 arch/x86/include/asm/idtentry.h:602 RIP: 0033:0x7faece99e0e1 Code: 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 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f RSP: 002b:00002000000001c0 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007faecec26090 RCX: 00007faece99e0d9 RDX: 0000000000000000 RSI: 00002000000001c0 RDI: 0000000000002000 RBP: 00007faecea35024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007faecec26128 R14: 00007faecec26090 R15: 00007ffe9fc505f8 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:3004 [inline] RIP: 0010:update_sit_entry_for_alloc fs/f2fs/segment.c:2399 [inline] RIP: 0010:update_sit_entry+0x4aa/0x1480 fs/f2fs/segment.c:2443 Code: 8b 45 d0 48 8d 58 18 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 f3 a8 8a ff 48 8b 1b 4c 01 fb 48 89 d8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 95 0e 00 00 44 0f b6 33 44 89 f0 44 08 RSP: 0018:ffffc90000a4e6e0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888141089440 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000a4e7b0 R08: ffff88811cbdc030 R09: 1ffff1102397b806 R10: dffffc0000000000 R11: ffffed102397b807 R12: 0000000000000002 R13: dffffc0000000000 R14: ffff888119c70000 R15: 0000000000000000 FS: 00007faecf7a16c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f89cafdd000 CR3: 000000012790a000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 8b 45 d0 mov -0x30(%rbp),%eax 3: 48 8d 58 18 lea 0x18(%rax),%rbx 7: 48 89 d8 mov %rbx,%rax a: 48 c1 e8 03 shr $0x3,%rax e: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) 13: 74 08 je 0x1d 15: 48 89 df mov %rbx,%rdi 18: e8 f3 a8 8a ff call 0xff8aa910 1d: 48 8b 1b mov (%rbx),%rbx 20: 4c 01 fb add %r15,%rbx 23: 48 89 d8 mov %rbx,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 0f 85 95 0e 00 00 jne 0xecc 37: 44 0f b6 33 movzbl (%rbx),%r14d 3b: 44 89 f0 mov %r14d,%eax 3e: 44 rex.R 3f: 08 .byte 0x8