Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037] CPU: 1 PID: 5089 Comm: syz-executor Not tainted 6.10.0-rc5-syzkaller-00018-g55027e689933 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline] RIP: 0010:lmLogSync+0x1e9/0xae0 fs/jfs/jfs_logmgr.c:937 Code: 00 00 49 8d 5f d8 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 55 99 d3 fe 48 8b 1b 48 83 c3 30 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 38 99 d3 fe 48 8b 3b e8 30 cb a6 RSP: 0018:ffffc900037d7b80 EFLAGS: 00010206 RAX: 0000000000000006 RBX: 0000000000000030 RCX: ffff88807dec3c00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900037d7c88 R08: ffffffff81cbb49a R09: 0000000000000000 R10: ffffc900037d7968 R11: fffff520006faf5b R12: ffff88807ce18800 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88802dce6438 FS: 000055558bd48500(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff5105af18 CR3: 000000006bfe0000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: jfs_syncpt+0x7d/0xa0 fs/jfs/jfs_logmgr.c:1041 jfs_sync_fs+0x8a/0xa0 fs/jfs/super.c:685 sync_filesystem+0xed/0x230 fs/sync.c:56 generic_shutdown_super+0x72/0x2d0 fs/super.c:621 kill_block_super+0x44/0x90 fs/super.c:1676 deactivate_locked_super+0xc4/0x130 fs/super.c:473 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1267 task_work_run+0x24f/0x310 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb747976e17 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:00007fff999410e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fb747976e17 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff999411a0 RBP: 00007fff999411a0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff99942250 R13: 00007fb7479e364a R14: 000000000001d430 R15: 00007fff99942290 Modules linked in: ---[ end ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 49 8d 5f d8 lea -0x28(%r15),%rbx 6: 48 89 d8 mov %rbx,%rax 9: 48 c1 e8 03 shr $0x3,%rax d: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) 12: 74 08 je 0x1c 14: 48 89 df mov %rbx,%rdi 17: e8 55 99 d3 fe call 0xfed39971 1c: 48 8b 1b mov (%rbx),%rbx 1f: 48 83 c3 30 add $0x30,%rbx 23: 48 89 d8 mov %rbx,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 48 89 df mov %rbx,%rdi 34: e8 38 99 d3 fe call 0xfed39971 39: 48 8b 3b mov (%rbx),%rdi 3c: e8 .byte 0xe8 3d: 30 cb xor %cl,%bl 3f: a6 cmpsb %es:(%rdi),%ds:(%rsi)