general protection fault, probably for non-canonical address 0xdffffc0000000008: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000040-0x0000000000000047] CPU: 0 PID: 23098 Comm: syz-executor Not tainted 6.6.101-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:208 [inline] RIP: 0010:lmLogSync+0x22f/0x9c0 fs/jfs/jfs_logmgr.c:937 Code: 86 b3 fe 4d 8d 7e f0 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 ef 62 dd fe 4d 8b 3f 49 83 c7 40 4c 89 f8 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 ff e8 d3 62 dd fe 49 8b 3f e8 5b 86 b3 fe RSP: 0018:ffffc9000b48fb80 EFLAGS: 00010202 RAX: 0000000000000008 RBX: dffffc0000000000 RCX: 2915a22c778b2800 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000b48fc88 R08: ffffc9000b48fae7 R09: 0000000000000000 R10: ffffc9000b48faa0 R11: fffff52001691f5d R12: ffff88801bf7d000 R13: dffffc0000000000 R14: ffff888065eb3c38 R15: 0000000000000040 FS: 000055557b165500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd360fb5000 CR3: 000000004508a000 CR4: 00000000003506f0 Call Trace: jfs_syncpt+0x7b/0x90 fs/jfs/jfs_logmgr.c:1041 jfs_sync_fs+0x87/0xa0 fs/jfs/super.c:685 sync_filesystem+0xea/0x220 fs/sync.c:56 generic_shutdown_super+0x6f/0x2b0 fs/super.c:666 kill_block_super+0x44/0x90 fs/super.c:1660 deactivate_locked_super+0x97/0x100 fs/super.c:481 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250 task_work_run+0x1ce/0x250 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f8edab8ff17 Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007fff69a3cd68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f8edac11c05 RCX: 00007f8edab8ff17 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff69a3ce20 RBP: 00007fff69a3ce20 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff69a3deb0 R13: 00007f8edac11c05 R14: 00000000002d8a04 R15: 00007fff69a3def0 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:208 [inline] RIP: 0010:lmLogSync+0x22f/0x9c0 fs/jfs/jfs_logmgr.c:937 Code: 86 b3 fe 4d 8d 7e f0 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 ef 62 dd fe 4d 8b 3f 49 83 c7 40 4c 89 f8 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 ff e8 d3 62 dd fe 49 8b 3f e8 5b 86 b3 fe RSP: 0018:ffffc9000b48fb80 EFLAGS: 00010202 RAX: 0000000000000008 RBX: dffffc0000000000 RCX: 2915a22c778b2800 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000b48fc88 R08: ffffc9000b48fae7 R09: 0000000000000000 R10: ffffc9000b48faa0 R11: fffff52001691f5d R12: ffff88801bf7d000 R13: dffffc0000000000 R14: ffff888065eb3c38 R15: 0000000000000040 FS: 000055557b165500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31109ff8 CR3: 000000004508a000 CR4: 00000000003506e0 ---------------- Code disassembly (best guess): 0: 86 b3 fe 4d 8d 7e xchg %dh,0x7e8d4dfe(%rbx) 6: f0 4c 89 f8 lock mov %r15,%rax a: 48 c1 e8 03 shr $0x3,%rax e: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1) 12: 74 08 je 0x1c 14: 4c 89 ff mov %r15,%rdi 17: e8 ef 62 dd fe call 0xfedd630b 1c: 4d 8b 3f mov (%r15),%r15 1f: 49 83 c7 40 add $0x40,%r15 23: 4c 89 f8 mov %r15,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1) <-- trapping instruction 2e: 74 08 je 0x38 30: 4c 89 ff mov %r15,%rdi 33: e8 d3 62 dd fe call 0xfedd630b 38: 49 8b 3f mov (%r15),%rdi 3b: e8 5b 86 b3 fe call 0xfeb3869b