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: 5903 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline] RIP: 0010:lmLogSync+0x1f2/0x9c0 fs/jfs/jfs_logmgr.c:937 Code: 86 85 fe 4d 8d 7e d8 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 0c e0 dc 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 f0 df dc fe 49 8b 3f e8 a8 f4 b2 fe RSP: 0018:ffffc9000486fb80 EFLAGS: 00010202 RAX: 0000000000000008 RBX: dffffc0000000000 RCX: ffff888020df1e00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000486fc88 R08: ffffc9000486fae7 R09: 0000000000000000 R10: ffffc9000486faa0 R11: fffff5200090df5d R12: ffff88805f55f000 R13: dffffc0000000000 R14: ffff88802e0e0438 R15: 0000000000000040 FS: 000055557f236500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fca62870000 CR3: 0000000025fce000 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:1259 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+0xf6/0x180 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: 0033:0x7fc2ae1902f7 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:00007ffd99a3aa88 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fc2ae211d7d RCX: 00007fc2ae1902f7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd99a3ab40 RBP: 00007ffd99a3ab40 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd99a3bbd0 R13: 00007fc2ae211d7d R14: 000000000002ca38 R15: 00007ffd99a3bc10 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline] RIP: 0010:lmLogSync+0x1f2/0x9c0 fs/jfs/jfs_logmgr.c:937 Code: 86 85 fe 4d 8d 7e d8 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 0c e0 dc 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 f0 df dc fe 49 8b 3f e8 a8 f4 b2 fe RSP: 0018:ffffc9000486fb80 EFLAGS: 00010202 RAX: 0000000000000008 RBX: dffffc0000000000 RCX: ffff888020df1e00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000486fc88 R08: ffffc9000486fae7 R09: 0000000000000000 R10: ffffc9000486faa0 R11: fffff5200090df5d R12: ffff88805f55f000 R13: dffffc0000000000 R14: ffff88802e0e0438 R15: 0000000000000040 FS: 000055557f236500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fca62862000 CR3: 0000000025fce000 CR4: 00000000003506e0 ---------------- Code disassembly (best guess): 0: 86 85 fe 4d 8d 7e xchg %al,0x7e8d4dfe(%rbp) 6: d8 4c 89 f8 fmuls -0x8(%rcx,%rcx,4) 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 0c e0 dc fe call 0xfedce028 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 f0 df dc fe call 0xfedce028 38: 49 8b 3f mov (%r15),%rdi 3b: e8 a8 f4 b2 fe call 0xfeb2f4e8