general protection fault, probably for non-canonical address 0xdffffc0000000009: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000048-0x000000000000004f] CPU: 1 PID: 3607 Comm: segctord Not tainted 6.0.0-syzkaller-09589-g55be6084c8e0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 RIP: 0010:_compound_head include/linux/page-flags.h:253 [inline] RIP: 0010:end_page_writeback+0x21/0x130 mm/folio-compat.c:26 Code: 00 eb b9 66 0f 1f 44 00 00 41 54 55 48 89 fd 53 e8 94 71 d3 ff 48 8d 7d 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 e4 00 00 00 4c 8b 65 08 31 ff 4c 89 e3 83 e3 01 RSP: 0018:ffffc90003f9fb20 EFLAGS: 00010216 RAX: dffffc0000000000 RBX: ffff888071099570 RCX: 0000000000000000 RDX: 0000000000000009 RSI: ffffffff81a7d8ac RDI: 0000000000000048 RBP: 0000000000000040 R08: 0000000000000001 R09: ffff888071099577 R10: ffffed100e2132ae R11: 0000000000000001 R12: ffff8880754f21f8 R13: dffffc0000000000 R14: 0000000000000040 R15: ffffea0002d63e00 FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000079554000 CR4: 0000000000350ee0 Call Trace: nilfs_segctor_complete_write fs/nilfs2/segment.c:1836 [inline] nilfs_segctor_wait fs/nilfs2/segment.c:1923 [inline] nilfs_segctor_do_construct+0x491a/0x6970 fs/nilfs2/segment.c:2086 nilfs_segctor_construct+0x8e3/0xb30 fs/nilfs2/segment.c:2375 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2483 [inline] nilfs_segctor_thread+0x3c3/0xf30 fs/nilfs2/segment.c:2566 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:_compound_head include/linux/page-flags.h:253 [inline] RIP: 0010:end_page_writeback+0x21/0x130 mm/folio-compat.c:26 Code: 00 eb b9 66 0f 1f 44 00 00 41 54 55 48 89 fd 53 e8 94 71 d3 ff 48 8d 7d 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 e4 00 00 00 4c 8b 65 08 31 ff 4c 89 e3 83 e3 01 RSP: 0018:ffffc90003f9fb20 EFLAGS: 00010216 RAX: dffffc0000000000 RBX: ffff888071099570 RCX: 0000000000000000 RDX: 0000000000000009 RSI: ffffffff81a7d8ac RDI: 0000000000000048 RBP: 0000000000000040 R08: 0000000000000001 R09: ffff888071099577 R10: ffffed100e2132ae R11: 0000000000000001 R12: ffff8880754f21f8 R13: dffffc0000000000 R14: 0000000000000040 R15: ffffea0002d63e00 FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f966c269290 CR3: 000000007ec55000 CR4: 0000000000350ef0 ---------------- Code disassembly (best guess): 0: 00 eb add %ch,%bl 2: b9 66 0f 1f 44 mov $0x441f0f66,%ecx 7: 00 00 add %al,(%rax) 9: 41 54 push %r12 b: 55 push %rbp c: 48 89 fd mov %rdi,%rbp f: 53 push %rbx 10: e8 94 71 d3 ff callq 0xffd371a9 15: 48 8d 7d 08 lea 0x8(%rbp),%rdi 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 20: fc ff df 23: 48 89 fa mov %rdi,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 0f 85 e4 00 00 00 jne 0x118 34: 4c 8b 65 08 mov 0x8(%rbp),%r12 38: 31 ff xor %edi,%edi 3a: 4c 89 e3 mov %r12,%rbx 3d: 83 e3 01 and $0x1,%ebx