EXT4-fs error (device loop0): ext4_mb_mark_diskspace_used:4215: comm syz.0.17: Allocating blocks 1-17 which overlap fs metadata ------------[ cut here ]------------ kernel BUG at fs/ext4/mballoc.c:4787! Oops: invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 1 UID: 0 PID: 6069 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:ext4_mb_use_inode_pa+0x6c1/0x720 fs/ext4/mballoc.c:4787 Code: e8 74 7e ad ff 48 ba 00 00 00 00 00 fc ff df e9 da fa ff ff e8 00 45 4b ff 90 0f 0b e8 f8 44 4b ff 90 0f 0b e8 f0 44 4b ff 90 <0f> 0b e8 e8 44 4b ff 90 0f 0b 48 8b 0c 24 80 e1 07 80 c1 03 38 c1 RSP: 0018:ffffc90004e4f3c8 EFLAGS: 00010293 RAX: ffffffff827467d0 RBX: 00000000ffffffff RCX: ffff888026db1e40 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 1ffff1100604d6ef R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed10081f9618 R12: 0000000000000004 R13: 0000000000000002 R14: 1ffff110081f961a R15: ffff888040fcb0d0 FS: 000055558c741500(0000) GS:ffff888126dee000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005586505f2950 CR3: 0000000043998000 CR4: 00000000003526f0 Call Trace: ext4_mb_use_preallocated+0x669/0x1410 fs/ext4/mballoc.c:5004 ext4_mb_new_blocks+0x5a1/0x46b0 fs/ext4/mballoc.c:6308 ext4_ext_map_blocks+0x1877/0x69c0 fs/ext4/extents.c:4383 ext4_map_create_blocks fs/ext4/inode.c:613 [inline] ext4_map_blocks+0x82c/0x16f0 fs/ext4/inode.c:816 ext4_alloc_file_blocks+0x425/0xdd0 fs/ext4/extents.c:4551 ext4_zero_range+0x38d/0xb90 fs/ext4/extents.c:4644 ext4_fallocate+0x340/0x3d0 fs/ext4/extents.c:4832 vfs_fallocate+0x672/0x7f0 fs/open.c:339 ksys_fallocate fs/open.c:363 [inline] __do_sys_fallocate fs/open.c:368 [inline] __se_sys_fallocate fs/open.c:366 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:366 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: 0033:0x7f1f34f2f749 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:00007ffef4af0c08 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f1f35185fa0 RCX: 00007f1f34f2f749 RDX: 0000000000000fff RSI: 0000000000000011 RDI: 0000000000000004 RBP: 00007f1f34fb3f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000008800000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1f35185fa0 R14: 00007f1f35185fa0 R15: 0000000000000004 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:ext4_mb_use_inode_pa+0x6c1/0x720 fs/ext4/mballoc.c:4787 Code: e8 74 7e ad ff 48 ba 00 00 00 00 00 fc ff df e9 da fa ff ff e8 00 45 4b ff 90 0f 0b e8 f8 44 4b ff 90 0f 0b e8 f0 44 4b ff 90 <0f> 0b e8 e8 44 4b ff 90 0f 0b 48 8b 0c 24 80 e1 07 80 c1 03 38 c1 RSP: 0018:ffffc90004e4f3c8 EFLAGS: 00010293 RAX: ffffffff827467d0 RBX: 00000000ffffffff RCX: ffff888026db1e40 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 1ffff1100604d6ef R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed10081f9618 R12: 0000000000000004 R13: 0000000000000002 R14: 1ffff110081f961a R15: ffff888040fcb0d0 FS: 000055558c741500(0000) GS:ffff888126dee000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005586505f2950 CR3: 0000000043998000 CR4: 00000000003526f0