Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037] CPU: 1 UID: 0 PID: 112 Comm: jfsCommit Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:write_special_inodes+0x71/0x170 fs/jfs/jfs_logmgr.c:207 Code: df e8 63 3b 6d fe 48 8d 7b 10 48 89 f8 48 c1 e8 03 80 3c 28 00 0f 85 c0 00 00 00 4c 8b 6b 10 49 8d 7d 30 48 89 f8 48 c1 e8 03 <80> 3c 28 00 0f 85 da 00 00 00 49 8b 7d 30 2e e8 cb af 17 08 48 8d RSP: 0018:ffffc90002db7bc8 EFLAGS: 00010216 RAX: 0000000000000006 RBX: ffff8880780dc200 RCX: ffffffff83509336 RDX: ffff88801f369e40 RSI: ffffffff834ffcfd RDI: 0000000000000030 RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffffffff81f4d650 R13: 0000000000000000 R14: ffff888040554800 R15: ffffc900026f9662 FS: 0000000000000000(0000) GS:ffff888124ad9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa6659156c0 CR3: 0000000012188000 CR4: 0000000000350ef0 Call Trace: lmLogSync+0xd2/0x820 fs/jfs/jfs_logmgr.c:935 jfs_syncpt+0x89/0xa0 fs/jfs/jfs_logmgr.c:1041 txEnd+0x30a/0x5a0 fs/jfs/jfs_txnmgr.c:550 txLazyCommit fs/jfs/jfs_txnmgr.c:2685 [inline] jfs_lazycommit+0x783/0xb30 fs/jfs/jfs_txnmgr.c:2734 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:write_special_inodes+0x71/0x170 fs/jfs/jfs_logmgr.c:207 Code: df e8 63 3b 6d fe 48 8d 7b 10 48 89 f8 48 c1 e8 03 80 3c 28 00 0f 85 c0 00 00 00 4c 8b 6b 10 49 8d 7d 30 48 89 f8 48 c1 e8 03 <80> 3c 28 00 0f 85 da 00 00 00 49 8b 7d 30 2e e8 cb af 17 08 48 8d RSP: 0018:ffffc90002db7bc8 EFLAGS: 00010216 RAX: 0000000000000006 RBX: ffff8880780dc200 RCX: ffffffff83509336 RDX: ffff88801f369e40 RSI: ffffffff834ffcfd RDI: 0000000000000030 RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffffffff81f4d650 R13: 0000000000000000 R14: ffff888040554800 R15: ffffc900026f9662 FS: 0000000000000000(0000) GS:ffff8881249d9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8ca87b12f8 CR3: 0000000035b76000 CR4: 0000000000350ef0 ---------------- Code disassembly (best guess): 0: df e8 fucomip %st(0),%st 2: 63 3b movsxd (%rbx),%edi 4: 6d insl (%dx),%es:(%rdi) 5: fe 48 8d decb -0x73(%rax) 8: 7b 10 jnp 0x1a a: 48 89 f8 mov %rdi,%rax d: 48 c1 e8 03 shr $0x3,%rax 11: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1) 15: 0f 85 c0 00 00 00 jne 0xdb 1b: 4c 8b 6b 10 mov 0x10(%rbx),%r13 1f: 49 8d 7d 30 lea 0x30(%r13),%rdi 23: 48 89 f8 mov %rdi,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1) <-- trapping instruction 2e: 0f 85 da 00 00 00 jne 0x10e 34: 49 8b 7d 30 mov 0x30(%r13),%rdi 38: 2e e8 cb af 17 08 cs call 0x817b009 3e: 48 rex.W 3f: 8d .byte 0x8d