Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037] CPU: 0 UID: 0 PID: 122 Comm: jfsCommit Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline] RIP: 0010:lmLogSync+0xfb/0x9d0 fs/jfs/jfs_logmgr.c:935 Code: 3c 87 fe 4d 8d 7e d8 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 b3 75 e6 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 97 75 e6 fe 49 8b 3f e8 af b0 bd fe RSP: 0018:ffffc9000397fb00 EFLAGS: 00010206 RAX: 0000000000000006 RBX: dffffc0000000000 RCX: ffff88801eff5940 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000397fc08 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc9000397fb60 R11: fffff5200072ff70 R12: 0000000000000001 R13: ffff88805082c800 R14: ffff888033be1638 R15: 0000000000000030 FS: 0000000000000000(0000) GS:ffff8881268bf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000004340 CR3: 000000006b678000 CR4: 00000000003526f0 Call Trace: jfs_syncpt+0x7b/0x90 fs/jfs/jfs_logmgr.c:1041 txEnd+0x2e5/0x530 fs/jfs/jfs_txnmgr.c:549 txLazyCommit fs/jfs/jfs_txnmgr.c:2684 [inline] jfs_lazycommit+0x55c/0xa10 fs/jfs/jfs_txnmgr.c:2733 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline] RIP: 0010:lmLogSync+0xfb/0x9d0 fs/jfs/jfs_logmgr.c:935 Code: 3c 87 fe 4d 8d 7e d8 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 b3 75 e6 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 97 75 e6 fe 49 8b 3f e8 af b0 bd fe RSP: 0018:ffffc9000397fb00 EFLAGS: 00010206 RAX: 0000000000000006 RBX: dffffc0000000000 RCX: ffff88801eff5940 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000397fc08 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc9000397fb60 R11: fffff5200072ff70 R12: 0000000000000001 R13: ffff88805082c800 R14: ffff888033be1638 R15: 0000000000000030 FS: 0000000000000000(0000) GS:ffff8881268bf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000004340 CR3: 000000006b678000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: 3c 87 cmp $0x87,%al 2: fe 4d 8d decb -0x73(%rbp) 5: 7e d8 jle 0xffffffdf 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 b3 75 e6 fe call 0xfee675cf 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 97 75 e6 fe call 0xfee675cf 38: 49 8b 3f mov (%r15),%rdi 3b: e8 af b0 bd fe call 0xfebdb0ef