Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037] CPU: 1 UID: 0 PID: 10235 Comm: syz.4.509 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:208 [inline] RIP: 0010:lmLogSync+0x244/0x9f0 fs/jfs/jfs_logmgr.c:937 Code: 5c ab fe 4d 8d 7e f0 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 0a eb d6 fe 4d 8b 3f 49 83 c7 30 4c 89 f8 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 ff e8 ee ea d6 fe 49 8b 3f e8 96 5c ab fe RSP: 0018:ffffc90006df7ae0 EFLAGS: 00010206 RAX: 0000000000000006 RBX: dffffc0000000000 RCX: 0000000000080000 RDX: ffffc9000e471000 RSI: 000000000000215e RDI: 000000000000215f RBP: ffffc90006df7bf8 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc90006df78c8 R11: fffff52000dbef46 R12: 0000000000000000 R13: ffff888034077000 R14: ffff88802a2a2e38 R15: 0000000000000030 FS: 00007f36a0abe6c0(0000) GS:ffff888126439000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561b6b5f6940 CR3: 0000000038cf6000 CR4: 00000000003526f0 Call Trace: jfs_syncpt+0x7b/0x90 fs/jfs/jfs_logmgr.c:1041 jfs_sync_fs+0x87/0xa0 fs/jfs/super.c:650 sync_filesystem+0x1ce/0x250 fs/sync.c:66 jfs_reconfigure+0xc6/0xa00 fs/jfs/super.c:370 reconfigure_super+0x227/0x8a0 fs/super.c:1080 do_remount fs/namespace.c:3391 [inline] path_mount+0xdc5/0x10e0 fs/namespace.c:4151 do_mount fs/namespace.c:4172 [inline] __do_sys_mount fs/namespace.c:4361 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4338 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f36a286da0a Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f36a0abde58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f36a0abdee0 RCX: 00007f36a286da0a RDX: 0000200000000f40 RSI: 0000200000000f00 RDI: 0000000000000000 RBP: 0000200000000f40 R08: 00007f36a0abdee0 R09: 0000000001a6a038 R10: 0000000001a6a038 R11: 0000000000000246 R12: 0000200000000f00 R13: 00007f36a0abdea0 R14: 0000000000000000 R15: 0000200000002cc0 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:208 [inline] RIP: 0010:lmLogSync+0x244/0x9f0 fs/jfs/jfs_logmgr.c:937 Code: 5c ab fe 4d 8d 7e f0 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 0a eb d6 fe 4d 8b 3f 49 83 c7 30 4c 89 f8 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 ff e8 ee ea d6 fe 49 8b 3f e8 96 5c ab fe RSP: 0018:ffffc90006df7ae0 EFLAGS: 00010206 RAX: 0000000000000006 RBX: dffffc0000000000 RCX: 0000000000080000 RDX: ffffc9000e471000 RSI: 000000000000215e RDI: 000000000000215f RBP: ffffc90006df7bf8 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc90006df78c8 R11: fffff52000dbef46 R12: 0000000000000000 R13: ffff888034077000 R14: ffff88802a2a2e38 R15: 0000000000000030 FS: 00007f36a0abe6c0(0000) GS:ffff888126439000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f01629f9000 CR3: 0000000038cf6000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: 5c pop %rsp 1: ab stos %eax,%es:(%rdi) 2: fe 4d 8d decb -0x73(%rbp) 5: 7e f0 jle 0xfffffff7 7: 4c 89 f8 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 0a eb d6 fe call 0xfed6eb26 1c: 4d 8b 3f mov (%r15),%r15 1f: 49 83 c7 30 add $0x30,%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 ee ea d6 fe call 0xfed6eb26 38: 49 8b 3f mov (%r15),%rdi 3b: e8 96 5c ab fe call 0xfeab5cd6