Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] 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 01/24/2026 RIP: 0010:metapage_write_folio+0xa7/0xcf0 fs/jfs/jfs_metapage.c:428 Code: fe 48 89 5c 24 18 4c 8d 73 18 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 b3 52 db fe 4d 8b 36 4c 89 f0 48 c1 e8 03 <42> 80 3c 38 00 74 08 4c 89 f7 e8 9a 52 db fe 49 8b 1e 43 c6 44 3c RSP: 0018:ffffc9000396f7c0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffea0000df5880 RCX: ffff88801d350000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000396f8d0 R08: ffffea0000df58b7 R09: 1ffffd40001beb16 R10: dffffc0000000000 R11: fffff940001beb17 R12: 1ffff9200072df04 R13: ffffea0000df5880 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881265c9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555ab60a28 CR3: 000000003062a000 CR4: 00000000003526f0 Call Trace: metapage_write_one+0x2c8/0x520 fs/jfs/jfs_metapage.c:818 release_metapage+0x5b9/0xab0 fs/jfs/jfs_metapage.c:884 txUnlock+0x509/0xdc0 fs/jfs/jfs_txnmgr.c:948 txLazyCommit fs/jfs/jfs_txnmgr.c:2683 [inline] jfs_lazycommit+0x52c/0xa10 fs/jfs/jfs_txnmgr.c:2734 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:metapage_write_folio+0xa7/0xcf0 fs/jfs/jfs_metapage.c:428 Code: fe 48 89 5c 24 18 4c 8d 73 18 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 b3 52 db fe 4d 8b 36 4c 89 f0 48 c1 e8 03 <42> 80 3c 38 00 74 08 4c 89 f7 e8 9a 52 db fe 49 8b 1e 43 c6 44 3c RSP: 0018:ffffc9000396f7c0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffea0000df5880 RCX: ffff88801d350000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000396f8d0 R08: ffffea0000df58b7 R09: 1ffffd40001beb16 R10: dffffc0000000000 R11: fffff940001beb17 R12: 1ffff9200072df04 R13: ffffea0000df5880 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881265c9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555ab60a28 CR3: 000000003062a000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: fe 48 89 decb -0x77(%rax) 3: 5c pop %rsp 4: 24 18 and $0x18,%al 6: 4c 8d 73 18 lea 0x18(%rbx),%r14 a: 4c 89 f0 mov %r14,%rax d: 48 c1 e8 03 shr $0x3,%rax 11: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) 16: 74 08 je 0x20 18: 4c 89 f7 mov %r14,%rdi 1b: e8 b3 52 db fe call 0xfedb52d3 20: 4d 8b 36 mov (%r14),%r14 23: 4c 89 f0 mov %r14,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 4c 89 f7 mov %r14,%rdi 34: e8 9a 52 db fe call 0xfedb52d3 39: 49 8b 1e mov (%r14),%rbx 3c: 43 rex.XB 3d: c6 .byte 0xc6 3e: 44 rex.R 3f: 3c .byte 0x3c