------------[ cut here ]------------ WARNING: fs/ext4/ext4_jbd2.c:75 at ext4_journal_check_start+0x24f/0x2b0 fs/ext4/ext4_jbd2.c:75, CPU#1: syz.0.640/12740 Modules linked in: CPU: 1 UID: 0 PID: 12740 Comm: syz.0.640 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:ext4_journal_check_start+0x24f/0x2b0 fs/ext4/ext4_jbd2.c:75 Code: 5b 41 5c 41 5d 41 5e 41 5f 5d e9 cc 20 6d 08 cc e8 a6 4d 57 ff 41 bf fb ff ff ff eb e0 e8 99 4d 57 ff eb d3 e8 92 4d 57 ff 90 <0f> 0b 90 eb c8 e8 87 4d 57 ff 90 0f 0b 90 43 80 7c 25 00 00 0f 85 RSP: 0018:ffffc900051573d8 EFLAGS: 00010287 RAX: ffffffff82685f2e RBX: ffff88805e284000 RCX: 0000000000080000 RDX: ffffc9001816e000 RSI: 00000000000008ba RDI: 00000000000008bb RBP: 0000000000000365 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed10070f6871 R12: dffffc0000000000 R13: 1ffff1100bc508f3 R14: ffff88805e284798 R15: 0000000000000001 FS: 00007f4108cc56c0(0000) GS:ffff888126dee000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4108cc4f98 CR3: 0000000032d92000 CR4: 00000000003526f0 Call Trace: __ext4_journal_start_sb+0x147/0x580 fs/ext4/ext4_jbd2.c:107 ext4_sample_last_mounted fs/ext4/file.c:869 [inline] ext4_file_open+0x732/0xa40 fs/ext4/file.c:901 do_dentry_open+0x7d0/0x1270 fs/open.c:962 vfs_open+0x3b/0x350 fs/open.c:1094 do_open fs/namei.c:4637 [inline] path_openat+0x342a/0x3df0 fs/namei.c:4796 do_filp_open+0x1fa/0x410 fs/namei.c:4823 do_open_execat+0x135/0x560 fs/exec.c:783 open_exec+0x40/0x60 fs/exec.c:822 bm_register_write+0x234/0x17a0 fs/binfmt_misc.c:820 vfs_write+0x287/0xb40 fs/read_write.c:684 ksys_write+0x14b/0x260 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f410aa7f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4108cc5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f410acd6090 RCX: 00007f410aa7f749 RDX: 000000000000004b RSI: 0000200000000140 RDI: 0000000000000004 RBP: 00007f410ab03f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f410acd6128 R14: 00007f410acd6090 R15: 00007ffe9d85e508